Category: What’s Up

After releasing What’s Up 2006 as an ebook, the biggest question we got was, “can I buy a printed copy?” I’m happy to report that the answer is now, “Yes!” Follow this link to go to Lulu.com. You can purchase a softcover edition of the book for $20.00 USD. Not bad for a 409-page book. We took the time and redid the pages and photos in the book so they look better printed, so I think you’ll be really happy with the result. The downloadable version is still completely free, but if you really like your words on paper, you’ve got that option too.

Click here to learn more.

Fraser Cain
Publisher
Universe Today

Uranus and its faint ring system which was discovered this week in 1977. Image credit: NASA/JPL. Click to enlarge.
If you haven’t had the chance to catch bright comet Pojmanski, the time is now. Head out this week to catch lunar features, bright stars and open clusters. Keep on looking because…

Here’s what’s up!

Monday, March 6 – Still making headlines, bright comet 2006/A1 Pojmanski is on the move. Easily spotted well before dawn with even small binoculars, Pojmanski has a very bright nucleus accompanied by a large, green-hued coma – along with reports of up to two degrees of tail. Now cruising through Aquila at an average magnitude of 5.4, it will continue to fade until it reaches Lacerta at month’s end. SkyHound provides excellent locator charts. Take the opportunity to locate this fine comet before the Moon returns to morning skies!

If you see sunshine today, celebrate the birthday of Joseph Fraunhofer born this date in 1787. The German scientist Fraunhofer was a true “trailblazer” of modern astronomy and his field was spectroscopy. After having served an apprenticeship as a lens and mirror maker, Fraunhofer went on to develop specialized optical instruments. While designing the modern achromatic objective lens for the telescope, he watched the sun’s light passing through a thin slit and saw many dark lines – part of the “rainbow bar code.” Fraunhofer knew some of these lines could be used as a wavelength “standard.” For this reason he began measuring their locations relative to one another. The most prominent of the lines he labeled with letters still in use today. His skill in optics, mathematics, and physics led Fraunhofer to design and build the very first diffraction grating capable of measuring the wavelengths of specific colors and dark lines in the solar spectrum. And his telescope – did it succeed? Of course. The achromatic objective lens is still a design of choice, and the binoculars you have? They’re achromats!

Tonight will be the perfect opportunity to find the lunar crater named for Fraunhofer. Return again to the now shallow appearing crater Furnerius. Can you spot the ring at its southern edge? This is crater Fraunhofer – a challenge under these lighting conditions.

Now, revisit the “Twin Stars” – Castor and Pollux. Separated by not much more than 3 arc seconds, 2.0 magnitude Castor A has a bright sibling – 2.8 magnitude Castor B. The pair is actually a true binary with an orbital period of roughly 500 years. The Castor system contains four lesser members – each main star is a spectroscopic binary. Without Fraunhofer’s discovery, we would have never known.

Although spectroscopes and telescopes are powerful instruments able to reveal much, sometimes you just have to get close for more details. Today in 1986, the first of over a week of flybys began as the Russian built VEGA 1 and European Space Agency’s Giotto became the first space probes to reach Halley’s Comet.

Tuesday, March 7 – On this date in 1792, the only child of William Herschel was born – John. Herschel became the first astronomer to thoroughly survey the southern hemisphere sky and he discovered photographic fixer – an important chemical ingredient needed to preserve images on photographic plates. Also born on this date in 1837 was Henry Draper, the man who made the first photograph of Vega’s stellar spectrum in 1872. Eight years later, he took the first picture of the Great Nebula in Orion. Draper’s contribution led to new techniques in astrophotography, making it possible for celluloid to reveal faint detail beyond the reach of the eye in the 1880’s. This led to development of the Great Observatories – and telescopes – necessary to ultimately show an expanding cosmos populated by numberless “island universes” beyond our own Milky Way.

Tonight’s outstanding lunar features are two craters that you simply can’t miss – Aristotle and Eudoxus. Located to the north, this pair will be highly prominent in binoculars as well as telescopes. The northernmost – Aristotle – was named for the great philosopher and has an expanse of 87 kilometers. Its deep, rugged walls show a wealth of detail at high power, including two small interior peaks. Companion crater Eudoxus, to the south, spans 67 kilometers and offers equally rugged detail.

If you haven’t been following Saturn with regularity, tonight’s bright Moon might make this an occasion to spend some quality time on the ring system and satellites. At magnifications above 100x, the main division separating Ring A from B (Cassini’s Division) should be readily apparent in most scopes. Try making a series of simple sketches showing any nearby “stars.” Keep the sketch as the Moon waxes to full and see if you can distinguish between background stars and the planet’s own retinue of six most easily observed satellites – Titan, Rhea, Tethys, Dione, Enceladus, and Iapetus.

Wednesday, March 8 – On this day in 1977, NASA’s airborne occultation observatory made an unexpected discovery – Uranus had rings. Human eyes didn’t actually see Uranus’ faint ring system at the time – only the strange wink of a star hidden behind them. Imaging the rings had to wait until Voyager 2 whisked by nine years later.

Tonight the Moon provides a piece of scenic history as we take a more in-depth look at a previous study crater – Albategnius. This huge, hexagonal, mountain-walled plain appears near the terminator about one-third the way north of the south limb. This 135 kilometer wide crater is approximately 14,400 feet deep and its west wall casts a black shadow on the dark floor. Partially filled with lava after creation, Albategnius is a very ancient formation that later became home to several wall-breech craters, such as Klein, which can be seen telescopically on the southwest wall. Albategnius holds more than just the distinction of being a prominent crater tonight – it also holds a place in history. On May 9, 1962 Louis Smullin and Giorgio Fiocco of the Massachusetts Institute of Technology (MIT) aimed a ruby laser beam toward the Moon’s surface and Albategnius became the first lunar feature to reflect laser light from Earth.

On March 24, 1965 Ranger 9 took a “snapshot” of Albategnius from an altitude of approximately 2500 km. Ranger 9 was designed by NASA for one purpose – to achieve lunar impact trajectory and send back high-resolution photographs and video images of the lunar surface. Ranger 9 carried no other science packages. Its destiny was to simply take pictures right up to the moment of impact. They called it… a “hard landing.”

Thursday, March 9 – Today is the 442nd anniversary of David Fabricius’ birth. Born in 1564, Fabricius discovered the first variable star – Mira. At the heart of Cetus the Whale, it is now dipping steeply to the south-southwest at skydark. Even when well placed above the horizon, you can’t always count on Mira being seen. At its brightest, Mira achieves magnitude 2.0 – bright enough to be seen 10 degrees above the horizon. However Mira “the Wonderful” can also get as faint as magnitude 9 during its 331 day long “heartbeat” cycle of expansion and contraction. Mira is regarded as a premiere study for amateur astronomers interested in beginning variable star observations. For more information about this fascinating and scientifically useful branch of amateur astronomy contact the AAVSO (American Association of Variable Star Observers).

Tonight’s featured lunar crater is located on the south shore of Mare Imbrium right where the Apennine mountain range meets the terminator. At 58 kilometers in diameter and 12,300 feet deep, Eratosthenes is an unmistakable crater. Named after the ancient Greek mathematician, geographer and astronomer Eratosthenes, this splendid crater will display a bright west wall and a black interior hiding its massive crater capped central mountain 3570 meters high! Extending like a tail, an 80 kilometer mountain ridge angles away to its southwest. As beautiful as Eratosthenes appears tonight, it will fade away to almost total obscurity as the Moon approaches full. See if you can spot it again in five days.

Friday, March 10 – Tonight would be a terrific opportunity to study under-rated crater Bullialdus. Located close to the center of Mare Nubium, even binoculars can make out Bullialdus when near the terminator. If you’re scoping – power up – this one is fun! Very similar to Copernicus, Bullialdus’ has thick, terraced walls and a central peak. If you examine the area around it carefully, you can note it is a much newer crater than shallow Lubiniezsky to the north and almost non-existent Kies to the south. On Bullialdus’ southern flank, it’s easy to make out its A and B craterlets, as well as the interesting little Koenig to the southwest.

Despite the bright waxing moon, we still have a chance to get a view of a sprinkling of faint stars high to the south at skydark. Located less than a finger-width west-northwest of Wezen (Delta Canis Majoris) – 6.5 magnitude NGC 2354 is achievable in small scopes. Although richly populated, this open cluster lacks a bright core. This may challenge the eye to see it. Despite the moonlight, about a dozen stars should be visible in smaller scopes, but return on a moonless night to look for faint clumps and chaining among its 50 or so brightest members.

Saturday, March 11 – Today celebrates the birth of Urbain Leverrier. Born in 1811, Leverrier predicted the existence of Neptune. Along with a similar prediction by John Couch Adams, this led to its discovery. As both a mathematician and astronomer, Leverrier was also the first scientist to promote the idea of daily weather forecasts.

Tonight we’ll have the opportunity to look for a lunar feature named for Leverrier. To find it, start with the C-shape of Sinus Iridum. Imagine that Iridum is a mirror focusing light – this will lead your eye to crater Helicon. The slightly smaller crater southeast of Helicon is Leverrier. Be sure to power up to capture the splendid north-south oriented ridge which flows lunar east.

Tonight let’s try a lovely triple star system – Beta Monocerotis. Located about a fist width northwest of Sirius, Beta is a distinctive white star with blue companions. Separated by about 7 arc seconds, almost any magnification will distinguish Beta’s 4.7 magnitude primary from its 5.2 magnitude secondary to the southeast. Now, add a little power and you’ll see the fainter secondary has its own 6.2 magnitude companion less than 3 arc seconds away to the east.

Sunday, March 12 – Tonight let’s turn binoculars or telescopes toward the southern lunar surface as we set out to view one of the most unusually formed craters – Schiller. Located near the lunar limb, Schiller appears as a strange gash bordered on the southwest in white and black on the northeast. This oblong depression might be the fusion of two or three craters, yet shows no evidence of crater walls on its smooth floor. Schiller’s formation still remains a mystery. Be sure to look for a slight ridge running along the spine of the crater to the north through the telescope. Larger scopes should resolve this feature into a series of tiny dots.

Want a challenging double this evening? Then let’s have a look at Theta Aurigae. 2.7 magnitude Theta is a four star system ranging in magnitudes from 2.7 to 10.7. The brightest companion – Theta B – is magnitude 7.2 and is separated from the primary by slightly more than 3 arc seconds. Remember that this is what is known as a “disparate double” and look for the two fainter members well away from the primary.

Grab a comet by the tail and may all your journeys be at light speed! …~Tammy Plotner. Contributing author: Jeff Barbour @ astro.geekjoy.com

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

AE Aurigaey. Image credit: T.A. Rector and B.A. Wolpa/NOAO/AURA/NSF. Click to enlarge.
UPDATE: Comet Pojmansk is in the observing news! Now rounding the Sun, it will make its nearest approach to Earth on March 5. At the beginning of the week it averages a magnitude approaching 7 and is brightening fast – possibly coming within unaided viewing range within days. By Monday morning it should reach visiblity for the northern hemisphere and reach a maximum elongation of 22 degrees. Check out a map from SkyHound and be on the lookout!!

Monday, February 27 – Today is the birthday of Bernard Lyot. Born in 1897, Lyot went on to become the inventor of the coronagraph in 1930. Although we cannot hand you a corona, we can show you a star that wears its own gaseous envelope.

Let’s go to our maps west of M36 and M38 to identify AE Aurigae. As an unusual variable, AE is normally around 6th magnitude and resides approximately 1600 light years distant. The beauty in this region is not particularly the star itself but the faint nebula in which it resides known as IC 405, an area of mostly dust and very little gas. What makes this view so entertaining is that we are looking at a “runaway” star. It is believed that AE once originated from the M42 region in Orion. Cruising along at a very respectable speed of 80 miles per second, AE flew the “stellar nest” some 2.7 million years ago! Although IC 405 is not directly related to AE, there is evidence within the nebula that areas have been cleared of their dust by the rapid northward motion of the star. AE’s hot, blue illumination and high energy photons fuel what little gas is contained within the region. Its light also reflects off the surrounding dust. Although we cannot “see” with our eyes like a photograph, together the pair forms an outstanding view for the small backyard telescope and it is known as “The Flaming Star.”

Tuesday, February 28 – Are you ready for a New Moon challenge? Then take advantage of dark sky time to head toward Orion. Tonight our aim is toward a single star – but there is much more hiding there than just a point of light!

Our first stop is the eastern-most star in the “belt,” Zeta Orionis, or better known as Alnitak. At a distance of some 1600 light years, this 1.7 magnitude beauty contains many surprises ? it’s a double star system. High power and steady skies are needed to make Alnitak’s duplicity clear, but if you want more, look a breath east and revisit the Flame Nebula – a fantastic field of nebulosity illuminated by Alnitak. The NGC 2024 is an outstanding region of nebulosity spread over an area the apparent size of a full moon.

Still not enough? Break out the big scope and put Zeta out of the field of view to the north at high power and allow your eyes to re-adjust. When you look again, you will see a long, faded ribbon of nebulosity called IC 434 south of Zeta. It stretches over a degree toward the south. The eastern edge of the “ribbon” is very bright and mists away to the west. Now hold your breath and look almost directly in the center. See that dark notch with two faint stars south of it? You have located one of the most famous of the Barnard dark nebulae – B33.

You may exhale now. B33 is also known as the “Horsehead Nebula.” This “Horsehead” is very tough visually – the classic chess piece appearance of a “knight” is only fully appreciated in photographs – but those of you who have large aperture can see a dark “notch,” improved with the use of a specific nebula filter. B33 is a small area cosmically, only about one light year in expanse. It’s nothing more than obscuring dark dust and non-luminous gas – but what an incredible shape! If you do not succeed at first attempt, try again. The “Horsehead” is one of the most challenging objects in the sky and has been observed with apertures as small as 150mm. This just might be your lucky “Knight”?

Wednesday, March 1 – George Abell was born this day in 1927. Abell cataloged 2712 clusters of galaxies based on the Palomar sky survey completed in 1958. Using plates taken by the 48-inch Oschin Schmidt telescope, Abell put forth the idea that the grouping of galaxy clusters related to the overall arrangement of matter in the universe. He developed the “luminosity function” – correlating brightness and number of members in clusters with distance. Abell also discovered a number of planetary nebulae and developed, along with Peter Goldreich, the theory of planetary evolution from red giants.

With the moon out of the picture early, why not get caught up in a galaxy cluster study – Abell 426. Located just 2 degrees east of Algol in Perseus, this group of 233 galaxies spread over a region of several degrees of sky is easy enough to find – but difficult to observe. Spotting Abell galaxies in Perseus can be tough in smaller instruments, but those with large aperture scopes will find it worthy of time and attention.

At magnitude 11.6, NGC 1275 is the brightest of the group and lies physically near the core of the cluster. Glimpsed in scopes as small as 150 mm aperture, NGC 1275 is a strong radio source and an active site of rapid star formation. Images of the galaxy show a strange blend of a perfect spiral being shattered by mottled turbulence. For this reason NGC 1275 is thought to be two galaxies in collision.
Depending on seeing conditions and aperture, galaxy cluster Abell 426 may reveal anywhere from 10 to 24 small galaxies as faint as magnitude 15. The core of the cluster is more than 200 million light-years away, so it’s an achievement to spot even a few!

Thursday, March 2 – Tonight the Moon appears as a very slender crescent setting to the west in Pisces. This lunar apparition looks very much like a pair of bright horns bearing a dark disk. Such a moon may have given rise to the ancient symbol associated with fertility goddesses originating in Egypt and Mesopotamia. Today we see it “as the old moon in the new moon’s arms.” To see this lunar phase is an Astronomical League challenge.

Skies darken early again tonight, so we’ll have a look at an open cluster easily seen in binoculars and well resolved in small scopes. Start at bright Castor and Pollux in Gemini and turn your eyes, binoculars, or finder scope almost due south to even brighter Procyon. Drop almost the same distance to Xi Puppis. Once you locate Xi, shift the scope or binoculars roughly one finger-width (two degrees) northwest. There you will see a hazy rectangular patch with a handful of barely resolvable stars in its midst – the open cluster M93.

First cataloged by Charles Messier in March of 1781, this wonderfully bright grouping contains a broad range of stellar types among its 80 or so members. Even at a distance of 3500 light-years, binoculars reveal the cluster’s bright haze and sharply angular swatch of core stars and a scope will resolve it. Towards the center, a wedge-shaped collection of bright members congregate. At the heart of the wedge is an easy double star – with another echoing the pair to the west. The very brightest of these stars are young, hot, and blue with an overall stellar population similar to the Pleiades. How old you ask? A very young one million years.

Friday, March 3 – With the Moon near the horizon, we have only a short time to view its features. Tonight let’s start with a central feature – Langrenus – and continue further south for crater Vendelinus. Spanning 92 by 100 miles and dropping 14,700 feet below the lunar surface, Vendelinus displays a partially dark floor with a west wall crest catching the brilliant light of an early sunrise. Notice also that its northeast wall is broken by a younger crater – Lame. Head’s up! It’s an Astronomical League challenge.

Once the Moon has set, revisit M46 in Puppis – along with its mysterious planetary nebula NGC 2438. Follow up with a visit to neighboring open cluster M47 – two degrees west-northwest. M47 may actually seem quite familiar to you already. Did you possibly encounter it when originally looking for M46? If so, then it’s also possible that you met up with 6.7 magnitude open cluster NGC 2423, about a degree northeast of M47 and even dimmer 7.9 magnitude NGC 2414 as well. That’s four open clusters and a planetary nebula all within four square arc-minutes of sky. That makes this a cluster of clusters!

Let’s return to study M47. Observers with binoculars or using a finderscope will notice how much brighter, and fewer, the stars of M47 are when compared to M46. This 12 light-year diameter compact cluster is only 1600 light-years away. Even as close as it is, not more than 50 member stars have been identified. M47 has about one tenth the stellar population of larger, denser, and three times more distant, M46.

Of historical interest, M47 was “discovered” three times: first by Giovanni Batista Hodierna in the mid-17th century, then by Charles Messier some 17 years later, and finally by William Herschel 14 years after that. How is it possible that such a bright and well-placed cluster needed “re-discovery?” Hodierna’s book of observations didn’t surface until 1984, and Messier gave the cluster’s declination the wrong sign, making its identification an enigma to later observers – because no such cluster could be found where Messier said it was!

Saturday, March 4 Born on this date in 1835, Giovanni Schiaparelli opened his eyes (and later ours) to a new world of possibilities – life on Mars. As director of Milan Observatory in 1877, Schiaparelli first described fine, faint features on the surface of Mars as “canali.” Perhaps one of Schiaparelli’s most important contributions was making the connection between meteor streams and the comets that produced them.

Tonight let’s return to our studies of the Moon and a more challenging crater. Further south than Vendelinus, look for another large, mountain-walled plain named Furnerius not too far from the terminator. Although it has no central peak, its walls have been broken numerous times by many smaller impacts. Look at a rather large one just north of central on the crater floor. If skies are stable, power up and search for a rima extending from the northern edge. Keep in mind as you observe that our own Earth has been pummeled just as badly as its satellite.

Sunday, March 5 – Today is the 494th anniversary of Gerardus Mercator’s birth in 1512. The famed mapmaker went on to live a life of great moral courage. Mercator’s time was a rough one for astronomy and astronomers. Despite a prison sentence and threats of torture and death for his “beliefs,” Mercator went on to design a globe of the earth in 1541 and one for the heavens ten years later. One sphere within a larger one – and all without the many complexities envisioned by Ptolemy a millennium before him.

Tonight the Moon provides an opportunity to view to a very changeable and eventually bright feature on the lunar surface – Proclus. At 28 km in diameter and 2400 meters deep, crater Proclus will appear on the terminator to the west of Mare Crisium’s mountainous border. Depending on your viewing time, it will seem to be about two-thirds shadowed, but the remainder of the crater will shine brilliantly. Proclus has an unusually high albedo, or surface reflectivity, of about 16%. This is uncommon for most lunar features. Watch this area over the next few nights as two rays from the crater widen and lengthen, extending approximately 320 kilometers north and south.

Now, just look at the Moon. Can you spot the Pleiades nearby?

Now let’s have a go at the dense open cluster NGC 2301. Located about two finger-widths northwest of visual double Delta Monoceros, this 6th magnitude cluster can be seen in binoculars as a small, faint haze divided by a line of barely resolved stars. Telescopes will reveal a half dozen bright stellar members, plus a number of small clumps of dimmer stars.

Keep rockin’ the night and may all your journeys be at light speed! ….~Tammy Plotner with additional writing by Jeff Barbour @ astro.geekjoy.com

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

M41. Image credit: NOAO/AURA/NSF. Click to enlarge.
Monday, February 20 – Today in 1962, John Glenn was onboard Friendship 7 and became the first American to orbit the Earth. As Colonel Glenn looked out the window, he reported seeing “fireflies” glittering outside his Mercury space capsule. Let’s see if we can find some…

The open cluster M41 in Canis Major is just a quick drift south of the brightest star in the northern sky – Sirius. Even the smallest scopes and binoculars will reveal this rich group of mixed magnitude stars and fill the imagination with strange notions of reality. Through larger scopes, many faint groupings emerge as the star count rises to well over 100 members. Several stars of color – orange in particular – are also seen along with a number of doubles.

First noted telescopically by Giovanni Batista Hodierna in the mid-1500s, ancient texts indicate that Aristotle saw this naked-eye cluster some 1800 years earlier. Like other Hodierna discoveries, M41 was included on Messier’s list – along with even brighter clusters of antiquity such as Praesepe in Cancer and the Pleiades in Taurus.
Open cluster M41 is located 2300 light years away and recedes from us at 34km/sec – about the speed Venus moves around the Sun. M41 is a mature cluster, around 200 million years old and 25 light years in diameter. Remember M41…Fireflies in night skies.

Tuesday, February 21 – Be sure to have a look at the Moon this morning before dawn, because Jupiter will be joining it!

Tonight Luna will rise well after midnight, so let’s return to look at two of the few globular clusters of the season. Starting with M79 in Lepus, head due south around 15 degrees into Columba – the Dove. There you’ll find a second winter cluster almost a full magnitude brighter than M79 – NGC 1851. Give it a try!

Want another challenge? Head for bright Alnitak – the easternmost star in Orion’s belt. Using medium to low power, carefully shift bright Alnitak out from the center of the field about a full moon’s width to the west. With dark skies, you will see a large, faint, tulip-shaped nebulosity broken by one or more dark lanes. This is the “Flame Nebula”
– NGC 2024. Congratulations. This one isn’t easy, but on the darkest of nights it may surprise you!

Wednesday, February 22 – If skies are clear this evening, all you need do is step outside as the last glow of the long-set Sun pales to the southwest. Prepare your eyes – and heart – to follow the great expanse of the many brilliant stars of the winter Milky Way. Arching from Puppis to Cassiopeia, you might also see a fading Deneb – crown star of the Northern Cross – descending west. If you live towards the southern hemisphere, you should see brilliant Canopus – second brightest star in the night sky high to the south. In honor of the many splendid lights of the winter Milky Way, take out your binoculars and explore the marvels that await you!

Did you find something in the binoculars that caught your eye? Why not get the scope out and see if you can track it down. Navigating with a scope can be a challenge. Things look differently by eye, binoculars, finderscope, and telescope, but that’s what learning the night sky is all about.

Thursday, February 23 – On this date in 1987, Ian Shelton made an astonishing discovery – a supernova. At 160,000 light years away, distant SN1987a was the brightest novae display seen in almost 400 years. More importantly, before it occurred, a blue star of roughly 20 solar masses was already known to exist in that same location within the Large Magellanic Cloud. Catalogued as Sanduleak -69?202, that star is now gone. With available data on the star, astronomers were able to get a “before and after” look at one of the most extraordinary events in the universe! Tonight, let’s have a look at a similar event known as “Tycho’s Supernova.”

Located northwest of Kappa Cassiopeia, SN1572 appeared so bright in that year that it could be seen with the unaided eye for six months. Since its appearance was contrary to Ptolemaic theory, this change in the night sky now supported Copernicus’ views and heliocentric theory gained credence. We now recognize it as a strong radio source, but can it still be seen? There is a remnant left of this supernova, and it is challenging even with a large telescope. Look for thin, faint filaments that form an incomplete ring around 8 arc minutes across.

Friday, February 24 – In 1968, during a radio-telescope search for quasars, Susan Jocelyn Bell discovered the first pulsar. At first the regularity of the pulses was so precise that Bell and her college advisor, D. A. Hewish, thought they might be receiving a signal from a distant civilization. It soon became clear as the number of these objects multiplied that all were natural – rather than artificial – phenomena. Two co-directors of the project, Hewish and Ryle, later matched Bell’s observations to the notion of a rotating neutron star. This won them the 1974 Physics Nobel Prize and proved a theory brought forward thirty years earlier by J. Robert Oppenheimer.
Tonight let’s take a journey just a breath above Zeta Tauri and spend some quality time with a pulsar embedded in the most famous supernova remnant of all. Factually, we know the Crab Nebula to be the remains of an exploded star recorded by the Chinese in 1054. We know it to be a rapid expanding cloud of gas moving outward at a rate of 1,000 km per second, just as we understand there is a pulsar in the center. We also know it as first recorded by John Bevis in 1758, and then later cataloged as the beginning Messier object – penned by Charles himself some 27 years later to avoid confusion while searching for comets. We see it revealed beautifully in timed exposure photographs, its glory captured forever through the eye of the camera — but have you ever really taken the time to truly study M1?

Then you just may surprise yourself…

In a small telescope, M1 might seem to be a disappointment – but do not just glance at it and move on. There is a very strange quality to the light which reaches your eye, even though initially it may just appear as a vague, misty patch. Allow your eyes to adjust and M1 will appear to have “living” qualities – a sense of movement in something that should be motionless. The “Crab” holds true to many other spectroscopic studies. The concept of differing light waves crossing over one another and canceling each other out – with each trough and crest revealing differing details to the eye – is never more apparent than during study. To observe M1 is to at one moment see a “cloud” of nebulosity, the next a broad ribbon or filament, and at another a dark patch. When skies are stable you may see an embedded star, and it is possible to see six such stars.

Many observers have the ability to see spectral qualities, but they need to be developed. From ionization to polarization – our eye and brain are capable of seeing to the edge of infra-red and ultra-violet. Even a novice can see the effects of magnetism in the solar “Wilson Effect.” But what of the spinning neutron star at M1’s heart? We’ve known since 1969 that M1 produces a “visual” pulsar effect. About once every five minutes, changes occurring in the neutron star’s pulsation affect the amount of polarization, causing the light waves to sweep around like a giant “cosmic lighthouse” and flash across our eyes. M1 is much more than just another Messier. Capture it tonight!!

Saturday, February 25 – Since we’ve studied the “death” of a star, why not take the time tonight to discover the “birth” of one? Our journey will start by identifying Aldeberan (Alpha Tauri) and move northwest to bright Epsilon. Hop 1.8 degrees west and slightly to the north for an incredibly unusual variable star – T Tauri.
Discovered by J.R. Hind in October 1852, T Tauri and its accompanying nebula, NGC 1555, set the stage for discovery with a pre-main sequence variable star. Hind reported the nebula, but also noted that no catalog listed such an object in that position. His observations also included a 10th magnitude uncharted star and he surmised that the star in question was a variable. On each count Hind was right, and both were followed by astronomers for several years until they began to fade in 1861. By 1868, neither could be seen and it wasn’t until 1890 that the pair was re-discovered by E.E. Barnard and S.W. Burnham. Five years later? They vanished again.

T Tauri is the prototype of this particular class of variable stars and is itself totally unpredictable. In a period as short as a few weeks, it might move from magnitude 9 to 13 and other times remain constant for months on end. It is about equal to our own Sun in temperature and mass
– and its spectral signature is very similar to Sol’s chromosphere – but the resemblance ends there. T Tauri is a star in the initial stages of birth!

T Tauri are all pre-main sequence and are considered “proto-stars”. In other words, they continuously contract and expand, shedding some of their mantle of gas and dust. This gas and dust is caught by the star’s rotation and spun into an accretion disc – which might be more properly referred to as a proto-planetary disc. By the time the jets have finished spewing and the material is pulled back to the star by gravity, the proto-star will have cooled enough to have reached main sequence and the pressure may have allowed planetoids to form from the accreted material.

Sunday, February 26 – Today is the birth date of Camille Flammarion. Born in 1842, he became a widely read author of astronomy and originated the idea that we were not alone – the notion of extraterrestrial intelligence. Yet, Flammarion was more than the great grandfather of SETI. In 1877, Flammarion found Charles Messier’s personal notes and catalog in an antiquarian book store. Based on those notes, he was able to identify M102 as Dreyer’s NGC 5866 and associate NGC 4594 with M104. Because of Flammarion’s hard work of scholarship and astronomical observation, two previously obscure references to faint studies in the Messier Catalogue were properly identified.

To locate these two studies, you’ll be waiting until around local midnight. Start at Iota Draconis and head about half a fistwidth in the direction of bright Arcturus to a solitary 5.2 magnitude star. Small, 10th magnitude M102 is about one degree due north toward Polaris. M104 – the “Sombrero Galaxy” – is just a bit more than a fistwidth west of Spica. At magnitude 8.3, it can be easily seen as a small faint glow in binoculars or finderscope. But it requires a telescope and a dark sky to hint at its namesake.

While you’re waiting for them to rise, relax and enjoy the Delta Leonid meteor shower. Entering our atmosphere at speeds of up to 24 kilometers per second, these slow travelers will seem to radiate from a point around the middle of Leo’s “back.” The fall rate is rather slow at 5 per hour, but any meteor trail is a delight to catch!

May all your journeys be at light speed… ~Tammy Plotner. With Jeff Barbour @astro.geekjoy.com

Lunar halo. Image credit: Steve Mandel. Click to enlarge.
Monday, February 13 – Tonight is Full Moon. During the month of February the upper northern hemisphere is often heavy with snow. Native Indian tribes of the north and east called February’s Full Moon the Full Snow Moon. Some tribes also referred to this Moon as the Full Hunger Moon as artic weather conditions often made hunting and food gathering very unproductive.

Tonight let’s have a look at a pair of single stars that make up Gemini (the Twins): Castor and Pollux.

In Greek mythology, Castor and Pollux were fathered by the Greek god Zeus (Jupiter) who took the form of a swan and came upon a beautiful mortal woman. Pollux later grew up to become a skilled boxer and Castor, a master horseman. The two brothers were inseparable. It is said that they rescued the beautiful Helen from Troy, traveled with Jason and the Argonauts, and ultimately found themselves in a mortal battle with another pair of twin brothers over a beautiful woman. Pollux was so grief stricken at Castor’s death that he cried out to Zeus and offered up his own immortality in exchange for Castor’s life. Zeus took pity on the twins and placed them in the sky. You can see them tonight with your own eyes joined seemingly eternally together in Gemini.

As you observe this pair note that although Castor is almost half a magnitude fainter than Pollux, Bayer gave that star the title “Alpha Geminorum.” Which one do you think appears brighter? There’s more about both stars to come.

Tuesday, February 14 – Happy Valentine’s Day! Today is the birth date of Fritz Zwicky. Born in 1898, Zwicky was the first astronomer to identify supernovae as a separate class of objects. His insights also proposed the possibility of neutron stars. Among his many achievements, Zwicky catalogued galaxy clusters and designed jet engines. He also suggested the redshift displayed in the spectra of distant galaxies could be caused by something other than universal expansion.

Tonight’s lunar feature for telescopes and binoculars is crater Langrenus. Named for the Belgian engineer and mathematician Michel Florent van Langren, crater Langrenus is easily found along the terminator slightly south of central. At this time its 132 km expanse will appear shallow and display a luminous central peak.

Since you have your scope out, why not turn it towards one of the brightest double stars in the night sky – Alpha Geminorum. It’s true. One of the twins is a twin! Separated by a little more than 3 arc seconds, this true binary pair of 2nd magnitude stars make Castor a splendid study – even in the smallest scopes.

Wednesday, February 15 – Born on this day in 1564 was the man who “fathered” modern astronomy – Galileo Galilei. Almost 4 centuries ago, Galileo became the first scientist to use a telescope for astronomical purposes and his first study was the Moon. His words, “Most beautiful and admirable is it to see the Moon’s luminous form… At nearly thirty diameters – some 900 times greater in region – anyone can perceive that the Moon is not covered with a smooth and uniform surface but in fact reveals great mountainous shelves, deep cavities, and gorges just like those of the Earth,” still echo true today.

Tonight the tiny crater named for Galileo will be visible on the surface, but seeing it – even in a telescope – will be a challenge. Look to the fully illuminated western edge. Almost central and caught on the edge of Oceanus Procellarum, you will see a small, bright ring. This is crater Reiner. You will find Galileo just a short hop to the northwest as a tiny, washed out feature. What a shame the cartographers did not pick a more vivid feature to honor the great Galileo!

Galileo is noted for making many wondrous discoveries, but did you know that he may have been the first astronomer to see the Trapezium in M42? Galileo included three of the four stars in a sketch based on what is probably a low power (27x) view of the Great Nebula. Tonight celebrate that unheralded discovery by using the lowest possible magnification and the smallest telescope you can find to get the “Galileo-eye view” of the Trapezium.

Thursday, February 16 – Today celebrates the birth of Francois Arago. Born in 1786, Arago was an early and enthusiastic supporter of the wave theory of light. His scientific achievements were many – including the 1811 invention of the polariscope. Arago was also a practiced astronomer and wrote 4 volumes entitled Astronomie Populaire in the mid-1800s. Arago’s polariscope revealed that light could be organized in such a way as to cause photons to have a similar electromagnetic orientation. Polarized light viewed through his polariscope could come close to disappearing when the instrument was rotated. Many amateur astronomers use polarizing filters to reduce the amount of glare from the Moon, but did you know that even starlight can be polarized?

In celebration of Arago’s birth, why not go out and have a look at one such star – Merope in the Pleiades. As you observe Merope keep in mind that its light doesn’t begin polarized. In passing through the Merope Nebula, it becomes filtered. Try using a polarized filter and compare the view without.

On this day in 1948, Gerard Kuiper was celebrating the discovery of Miranda – one of Uranus’ moons. At magnitude 16, few of us will ever see Kuiper’s discovery for ourselves. With Uranus now close to the Sun (near Lambda Aquarii), even it will be hard to see!

Friday, February 17 – For SkyWatchers this morning, many of you will have the opportunity to watch the Moon occult bright Spica – Alpha Virginis. Be sure to check with IOTA for times and locales.

Early evening means dark skies, so let’s take the opportunity to revisit two of the three Messier open clusters in Auriga and compare them with the similar, but fainter, NGC 1893.

NGC 1893 is similar to M36 in size, but four times fainter. On a good night, a small telescope can resolve more than a dozen faint stars in this 13,000 light-year distant open cluster. To find it, look around 3 degrees southwest of M38 and west of M36. The three clusters form an even triangle in the sky. In large binoculars or a rich-field telescope, the trio can be seen together as nebulous mists sprinkled with faint stars. Remember this cluster is also four times more distant than the Messier objects it shares Auriga with. It is estimated to be 10 million years old and it’s still in the process of giving birth to new stars. Reflection nebula IC 410 is also part of the NGC 1893. See if you can spot it!

Saturday, February 18 – On this day in 1930, a young man named Clyde Tombaugh was very busy with some photographic plates taken with the Lowell Observatory’s 13″ telescope. His reward? The discovery of Pluto!

Clyde discovered Pluto on a set of plates centered on the star Delta Geminorum – Wasat – a star lying very near the path the Sun takes across the sky. While we can’t see Pluto tonight, we can study this fine 3.5 magnitude star and its disparate companion.

Once you’ve studied Wasat, you may notice Saturn gracing the early evening sky. As you observe Saturn’s magnificent ring system and four or five brightest moons, give some thought to distance and size. If our solar system was measured in units based on the Saturn-Sun distance – rather than Earth-Sun, Pluto would be 3.4 AUs from Sol. At 2274 kilometers in diameter, Pluto is less than half the size of Saturn’s largest satellite – Titan!

For deep sky, have a look at the rich open cluster NGC 2129. Located about a fingerwidth west of M35, at low power it may appear in the same field as Propus – 1 Geminorum. A rich-field scope or binoculars will frame M35 and NGC 2129 together.

Sunday, February 19 – Today is the birthday of Nicolas Copernicus. Born in 1473, Copernicus envisioned the modern solar system model which explained the retrograde motion of the outer planets. Considering this was well over 530 years ago, and in a rather unenlightened time, his revolutionary thinking is astounding. If you are up later, you can see the mighty crater named for Copernicus on the lunar surface almost central and west of the terminator.

But, before the Moon rises tonight, let’s turn our telescopes towards Saturn – one solar system body whose motion through the heavens exemplifies much of what Copernicus hoped his concept could explain! Among the “seven classical planets,” Saturn moves the slowest, taking almost two and a half years to move the thirty degrees related to each of the twelve “stations” planets pass through as they circle the ecliptic. Because of its slow pace, Saturn is often associated with “Chronos,” or Father Time, who wields his scythe and harvests a 30 year-long generation of humankind. Right now, Saturn is stationed in Cancer the Crab – one of the twelve “zodiacal,” or “animal signs” of the ecliptic. The Crab is joined with eleven other animals – preceded by neighboring Gemini, “the twin men,” and followed by Leo, “the solitary Lion.” By putting the Sun in the center of all this – rather than the Earth – Copernicus freed human thinking from the more ancient Ptolemaic system and allowed the solar Lion to stand at the center of things instead.

So, have another look at Saturn. Enjoy its low-contrast southern equatorial belt, subtly mottled blue polar region, and fine system of four easily seen satellites each moving much more rapidly around Saturn than the planet itself does around the Sun. Then think “Wow, that Copernicus guy would really have enjoyed seeing this!”

May all your journeys be at light speed… ~Tammy Plotner. Contibuting writer: Jeff Barbour @ astro.geekjoy.com

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

Apollo 16. Image credit: NASA. Click to enlarge.
Monday, February 6 – On this day in 1971, astronaut Alan Shepherd became the first “lunar golfer” to tee off on the Moon’s surface. While the Apollo 14 landing site is just on the other side of the terminator tonight, we can still go “crater hopping” to catch another. Close to the terminator and about one third of the way from the southern cusp are the ancient walls of huge previous studied Albategnius. Directly to its lunar east, and about the same distance as Albategnius’ is wide, look for a trio – small western Andel, larger eastern Descartes, and larger still southern Abulfeda. Power up! Between Andel and Descartes is the small pockmark of Dolland. North of Dolland is a ruined, unnamed crater with a pronounced set of rings on its northwestern shore. On the eastern edge of the relatively smooth floor, the remains of the Apollo 16 mission still shine on!

Tonight we’ll finish up our sweep for stardust through Auriga. Start at Theta and head due south five degrees (half a fist). On most nights, M37 gives an extraordinarily dense and complex view of more than 100 stars to small scopes, but lunacy will prevent that. Power up to darken the field.

Now let’s talk about these three interesting open clusters. All were discovered by Giovanni Batista Hodierna before the year 1654 – more than a decade before Messier cataloged them. All are located roughly 4000 light years away from Earth. The smallest of the three, M36, spans 12 light years. That’s not much more than the distance between our Sun and Epsilon Eridani. Larger M37 and M38 span about 25 light years, or about the distance between us and Vega. We’ll come back for a look at all three later in the month.

Tonight observers in western North America and Hawaii should follow the progress of the Moon as it passes through the Pleiades!

Tuesday, February 7 – On this day in 1889, the first American national astronomy organization was born – the Astronomical Society of the Pacific.

Tonight, let’s return to the Moon and previous study Plato. To the south on the dark plains of Mare Imbrium, you will notice an almost star-like point of light, a singular peak named Mons Pico. Unique among lunar mountains, its highly reflective rocky composition makes it appear almost like a pyramid in the long shadows of sunrise. “Pyramid” Pico stands 8,000 feet above the lunar plane on a base some 18 miles wide!

After looking at a solitary mountain this evening, let’s have a look at a solitary star as well – Alpha Orionis. Although its designation lists it as Orion’s brightest star in Johann Bayer’s Uranometria of 1603, Betelgeuse is actually slightly fainter than Beta (Rigel). What makes it special is its color. To the eye, Betelgeuse appears a distinctive red-orange. This color relates directly to its spectral class of M2. Like many M-spectra stars, Betelgeuse truly is a “red giant” – a star approaching the end of its life. With an immensely swollen, low temperature, near-vacuum photosphere of hydrogen and helium gas, this star measures some 300 million miles in diameter. Placed at the Sun’s position, it would extend out beyond the orbit of Mars! At 430 light years away, Betelgeuse is not the farthest or bright stars of winter, but it is most certainly the largest.

Wednesday, February 8 – Today celebrates the birth of J.L.E. Dreyer. Born in 1852, the Danish Dreyer came to fame as the astronomer who compiled the New General Catalogue (NGC) published in 1878. As a professional, Dreyer began his observations of the night sky in the employ of Lord Rosse at Birr Castle Ireland. Later Dreyer moved to Armagh Observatory where he confirmed many of the deep sky studies compiled by William Herschel and other observers using the 10″ refractor he secured funds for and selected as his instrument of choice. Even with a wealth of astronomical catalogs to choose from, the NGC objects, and Dreyer’s abbreviated list of descriptions, still remain the most widely used today.

Let’s engage is some further lunar exploration as crater Copernicus again becomes visible tonight to even the most modest of optical aid. Small binoculars show Copernicus as a bright “ring” midway along the lunar dividing line of light and dark called the “terminator.” Telescopes will reveal its 97 km (60 mile) expanse and 120 meter (1200 ft.) central peak to perfection. Copernicus holds special appeal as it’s the aftermath of a huge meteoric impact. At 3800 meters (12,600 feet) deep, its walls are around 22 km (14 miles) thick and over the next few days, the impact ray system extending from this tremendous crater will become wonderfully apparent.

Now, let’s explore something special from J.L.E’s lifework. Let’s turn eyes, binoculars, and scopes on Orion’s Belt and the brightly scattered open cluster NGC 1981. On a dark, moonless night, NGC 1981 can be seen unaided as a small, fuzzy haze in Orion’s “sword.” Let’s start by using binoculars – or finderscope – to get a sense of how 1981 “fits in” with the area. Do you see those three 6th magnitude stars at the top? They’re part of the 1981 cluster. Now look south to 4.6 magnitude 42 Orionis – a tight, disparate double. You probably won’t see M43 further south, but M42 will be visible. Try observing multiple system Iota Orionus. After the low power tour, head back to the top of the list with a telescope and enjoy the dozen or so brightly scattered, hot young stars that make up number 1981 on J.L.E Dreyer’s celestial list!

Thursday, February 9 – It’s a “Moon Gazer’s” evening as our nearest astronomical neighbor continues to light up the night sky. Don’t put away your telescopes and binoculars thinking there’s nothing to view though, because one of the most “romantic” features on the lunar surface will be highlighted tonight.

The Sinus Iridium is one of the most fascinating and idyllic regions of the Moon. At 241 km (150 miles) in diameter and ringed by the Juras Mountains, it’s known by the quiet name of “The Bay of Rainbows.” Despite this serene name, the region was actually formed by cataclysm. Astronomers speculate that a minor planet of around 200 km in diameter once impacted our newly formed Moon with a glancing strike. This caused “waves” of superheated material to wash up along a “shoreline” forming this delightful C-shaped lunar feature. The effect of looking at a bay is stunning as the smooth inner sands show soft waves called “rilles,” broken only by a few small, impact craters. This picture is completed as Promentoriums Heraclides and LaPlace rise above the surface (at 1800 meters and 3000 meters respectively) appearing as distant “lighthouses” standing at the entrance.

It’s also a great time for seeing double. Before it moves too high overhead, have a look at 41 Aurigae. The pair ? one of 5th and other of the 7th magnitude – is separated by 8 arc seconds. Notice how the companion orients almost due north of its brighter primary. The result appears as two stars moving side-by-side across the field of view! 41 Aurigae and it secondary are members of the Hyades. To locate 41, start at Beta Aurigae. Use your finderscope to center on Pi – a little more than a degree north. 41 is a slightly fainter star around five degrees northeast of Pi. It’s a challenge to locate – but it means is that you can congratulate yourself when you find it! And enjoy observing it all the more…

Friday, February 10 – Let’s return to the Moon tonight and explore an area to the south around another easy and delightful lunar feature – the crater Gassendi. At 110 km in diameter and 2010 meters deep, this ancient crater contains a triple mountain peak in its center. Once one of the most “perfect circles” on the Moon, the south wall of Gassendi has been eroded by lava flows over a 48 km expanse and offers numerous detailed features to telescopic observers on its ridge and rille covered floor. Observing with binoculars? Gassendi’s bright ring stands on the north shore of Mare Humorum…an area about the size of the state of Arkansas!

Are you ready for a tough double star? Alnitak (Zeta Orionis) is the easternmost star of Orion’s belt. It’s a double just wide enough to resolve through any telescope. However, you’ll need steady skies to show the two bright stars as distinct and tiny orbs of light separated by a mere 2.3 arc seconds. While observing this tight couple, keep in mind that both stars are some 800 light-years distant and that Zeta-A has one of the hottest photospheres among all known stars. At 31,000 degrees K, its temperature is so high that it shines primarily in the ultraviolet. Look for a third, 10th magnitude star almost 1 arc minute away from the bright pair. When you can see this one plainly, you’re ready to start looking for fainter members of the famed Trapezium found in the heart of M42.

Saturday, February 11 – On this day in 1970, Lambda 4S-5, the first Japanese satellite was launched.

The waxing Moon will dominate early evening skies, but tonight is an excellent opportunity for binoculars and telescopes to explore crater Tycho.

Named for Danish astronomer, Tycho Brahe, this fantastic impact crater is very impressive in even the most modest of optical aids. Spanning 85 km, this lunar feature will be very prominent and unmistakable in the southern hemisphere of the Moon. Tycho’s highly conspicuous ray system supports its origin as an impact crater. The rays span hundreds of kilometers across the lunar surface. Tycho is also one of the youngest of the major features at an astounding age of only 50,000,000 years old!

On January 9, 1968 Surveyor 7 – the last lunar robot of its kind – landed quietly at lunar sunrise on Tycho’s slopes. Because previous Surveyor missions provided the Apollo program with all data necessary for manned missions, Surveyor 7’s presence was scientific only. Two weeks later, when the Sun set on the landing site, Surveyor 7 had provided over 21,000 photographs, determined physical and chemical properties associated with the Southern Highland area, and detected laser beams aimed at it from two separate Earth observatories.

With the Moon lighting the skies, tonight will give you and opportunity to see just how much effect it has on studies. In the spirit of investigation, have a look at the Great Nebula in Orion. Not quite the glorious sight you remember, huh? But while in M42, power up a little and have a look at those four stars in its midst. We will be back…

Sunday, February 12 – Tonight the Moon will command the skies and give naked-eye observers an opportunity to use their imaginations!

Since the dawn of mankind, we have been gazing at the Moon and seeing fanciful shapes in large lunar features. Tonight, as the Moon rises, is your chance to catch an AL lunar challenge – “The Rabbit in the Moon.” The “Rabbit” is a compilation of all the dark maria. The Oceanus Procellarum forms the “ear” while Mare Humorum makes the “nose.” The “body” is Mare Imbrium and the “front legs” appear to be Mare Nubium. Mare Serenitatis is the “backside” and the picture is complete where Mare Tranquillitatis and Mare Fecunditatis shape the “hind legs” with Crisium as the “tail.”

See the Moon with an imaginative mind and new eyes — and find the “Rabbit.” It’s already out of the hat and in the heavens…

For telescopes and binoculars, the lunar surface will provide a bright but superior view of crater Grimaldi. Named for Italian physicist and astronomer, Francesco Grimaldi, this deep grey oval is one of the darkest features on the Moon – only reflecting about 6% of the light. Approximately 430 km (140-145 miles) long, it’s easy to spot along the terminator and just slightly south of the center of the lunar limb. Tonight is the best time to view its mountained walls, for later they will disappear and Grimaldi will take on the appearance of a small mare in the light of the full Moon.

Before then, let’s look at another fine double star – Eta Orionus. Eta is the 3.4 magnitude star a little over 6 degrees north-northeast of Rigel. Like Alnitak, Eta has a bright, closely spaced companion. Look for a much fainter 9.4 magnitude star that may not be part of the system. Like Alnitak, almost any size telescope can split the pair, but it will take a still sky to fully distinguish each star clearly.

May all your journeys be at light speed… ~Tammy Plotner. Contributing writer – Jeff Barbour @ astro.geekjoy.com

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

M43: “The Fishmouth”. Image credit: N.A. Sharp/NOAO/AURA/NSF. Click to enlarge.
Monday, January 30 – The Moon is now a thin crescent at sunset but no problem for dark sky observing. Tonight let’s have a look at the “Great Nebula” in Orion and its shy neighbor – M43.

M43 has its own special beauty. First discovered by Jean-Jacques D’Ortous de Mairan in the early eighteenth century, M43 is actually a continuation of M42 blocked by a dark slash of nebulosity called the “Fishmouth.” The star illuminating M43 is variable NU Orionus – which ranges about one magnitude in brilliance. Like its overpowering neighbor, M43 is a stellar nursery with the beginnings of its own cluster held close to its heart.

Tuesday, January 31 – Tonight in 1862, Alvan Graham Clark, Jr. made an unusual discovery. While watching Sirius, Clark uncovered the intense star’s faint companion while testing an 18″ refractor for Dearborn Observatory. The scope itself was built by Clark, his father and his brother. Imagine his excitement when it turned up the white dwarf – Sirius B! Based on the strange way Sirius A wobbles in the sky, Friedrich Bessel proposed its B’s existence back in 1844, but this is the first time it was confirmed visually.

Sirius B is nicknamed “the Pup,” and tonight we’ll have a serious look at Sirius, and see what it takes to uncover its little companion. Sirius is the brightest star that normally graces the night sky. At magnitude -1.6, it produces so much light that the atmosphere won’t stand still for it – sometimes even flashing in vibrant colors! This means that poor “Pup” hardly stands a chance of being seen. At magnitude 8.5 it could easily be caught in binoculars if it were on its own. So how do you find it? First, you’ll need a mid-to-large telescope with a high power eyepiece. Second, add a stable evening – not night – sky around the time Sirius is as high up as possible. Third, you’ll have to train your eye to perceive something that will cause you to say “I could hardly believe my eyes!” – because it’s that faint. Seeing the Pup is a Sirius matter, but practice will help you walk “the Pup” out of the evening sky!

If you had problems finding it, don’t worry… Others have problems, too. On this night in 1948, the first test photos using the Hale 5-meter (200-inch) telescope at Mt. Palomar were underway. Believe it or not, problems with the configuration and mounting of the mirror meant that it was almost 2 years later before the first observing run was made by a scheduled astronomer!

Wednesday, February 1 – The Moon has returned. Could you spot its slender crescent last night? If not, then try again tonight as we aim binoculars and telescopes toward the lunar surface.

Look almost centrally on the terminator for the very conspicuous crater Langrenus. Depending on your viewing location and time, it may be divided by the terminator, but will be quite recognizable. Spanning 85 miles in diameter, the steep, rugged walls rise almost 16,200 feet above the crater’s floor and you’ll see their bright outline on the western edge. Can you spot its central peak? It’s small for a crater this size and will present a challenge for binoculars.

While we’re out, let’s revisit the Crab Nebula in Taurus – there’s so much to learn and see about this very special nebula. The label “planetary” is a definite misnomer. Unlike most with this designation, M1 hardly looks like a globe and varies in other significant ways. Most planetaries have central stars that spew out atmospheric gases on a regular basis – but not this one. M1 did it all at once and we know exactly when it happened.

As one of only about 20 supernovae seen before the invention of the telescope, 11th century Chinese astronomers thought it four times brighter than Venus. Seen in broad daylight, the supernova remained visible for more than three weeks and continued to be seen in the night sky for almost two years. The position recorded for that July 4th, 1054 AD discovery now corresponds with that of the Crab Nebula.

Thursday, February 2 – There’s no missing the Moon tonight, so let’s go explore. Notice how crater Langrenus has changed in just 24 hours! Our study will be a trio of craters that look very much like a?? paw print on the surface. Just northeast of Langrenus’ border, look for the collection of Naonobu (north), Atwood (south) and Bilharz (west). Power up and try an even more challenging crater almost on the edge of Langrenus’ northern rim. This small pock-mark is known as Acosta.

When the Moon has begun to set, let’s have a look at a pair of neighboring open clusters in Gemini – M35 and NGC 2158. While both can be seen in the same low-power field, only M35 is visible in binoculars – as a round nebulosity as large as the Moon’s disc and peppered with faint stars. This is precisely how NGC 2158 looks in a mid-sized telescope. Like many of the brighter Messier studies, M35 was observed by others before Charles began looking for comets and kept running into deep sky objects. Keep in mind as you view these two galactic clusters that faint NGC 2158 is 16,000 light years away. That’s five times more distant than M35!

Tomorrow morning, observers in far western North America and Hawaii, will have the opportunity to see the Moon occult 4.5 magnitude Epsilon Piscium. Check the IOTA webpage to determine times and locales for Epsilon’s disappearance on the Moon’s shadowed side and reappearance on its bright limb. Keep the site bookmarked and use it as a reference throughout the observing year for other similar events.

Friday, February 3 – On this day in 1966, the first soft landing on the Moon occurred as Soviet probe Luna 9 touched down and sent back the very first pictures from the surface. Although Luna 9’s landing area in the Oceanus Procellarum is not visible tonight, we’ll discover two giants – Atlas and Hercules.

Located in the northeastern quarter of the lunar surface, this pair of craters is very prominent tonight in either binoculars or telescopes. The smaller, western crater is Hercules and the larger one is Atlas. When Hercules is near the terminator its western bright wall is in strong contrast to an interior so deep that it remains in shadow. Spanning 45 miles in diameter and plunging down 12,500 feet, Crater Hercules also contains an interior crater revealed as the Sun rises over it in the next 24 hours. Far more detail tonight is shown in much older crater Atlas. Spanning 54 miles in diameter and more shallow at 10,000 feet, Atlas contains a small interior peak. Power up and see if you can spot a Y-shaped crack along Atlas’ floor known as the Rimae Atlas.

If you’re in the mood to stay out a bit later, let the Moon set and have a look at the Eskimo Nebula (NGC 2392) in Gemini. Discovered by William Herschel in 1787, the 5000 light year distant NGC 2392 gives the appearance of a parka hooded face in large telescopes. In the center is a single 10th magnitude star – the source of both the planetary’s nebulosity and its light. Smaller scopes easily show both the central star and bright mantle of gas with a hint of “fuzzy” around the edge. Although the Eskimo is looking at us – it’s moving away at 75 km per second.

To find the “Eskimo,” start at Delta Geminorum and look about a finger width east/southeast for dim star 63. NGC 2392 is a little more than half a degree southeast, very near the ecliptic. Power up to get the best possible view of this 10th magnitude beauty. For those with a nebula filter, try it. This particular nebula will look much like a glowing green telrad.

Saturday, February 4 – Today is the birthday of Clyde Tombaugh. Born in 1906, Tombaugh discovered Pluto 24 years and two weeks after his birth. It will be a few months before we have an opportunity to see Pluto, but it’s grand to think that hard work and perseverance can accomplish some extraordinary things.

Let’s have a look at the lunar surface tonight and return to crater Posidonius. Located on the northeast shore of Mare Serenitatis and near the terminator, this large, ancient walled plain is an example of a Class V crater. Posidonius appears to be very flat – and with good reason. While its dimensions are roughly 52 by 61 miles, the crater itself is only 8,500 feet deep. The bright ring of the structure remains conspicuous to binoculars throughout all lunar phases, but a telescope is needed to appreciate the many fine features found on Posidonius’ floor. Power up to observed the stepped, stadium-like wall structure and numerous resolvable mountain peaks joining its small, central interior crater.

Before the Moon dominates the evening skies, let’s turn our attention towards the faintest of the three Messier open clusters in Auriga – M38. You’ll find it located almost precisely between Iota and Theta Aurigae. This 6.4 magnitude galactic cluster resolves into more than two dozen stars in small scopes, with its brighter members giving the appearance of an “X” in space. Like M35, M38 shares the field with a much fainter and denser companion. Look another half degree see to find the 8th magnitude cluster NGC 1907.

Sunday, February 5 – On this day in 1963, Maarten Schmidt measured the first redshift of a distant quasar and revealed just how luminous these stellar appearing objects are. And in 1974 the first close-up photograph of Venus was made by Mariner10.

The most outstanding feature tonight on the Moon will be a southern crater near the terminator – Maurolycus. Depending on your viewing time, the terminator may be running through it. These shadows will multiply its contrast many times over and display its vivid formations. As an Astronomy League challenge, Maurolycus will definitely catch your eye with its black interior and western crest stretched over the terminator’s darkness. Too many southern craters to be sure? Don’t worry. Maurolycus dominates them all tonight. Look for its double southern wall and multiple crater strikes along its edges.

Now let’s journey towards Auriga and drop a fist’s width south of Alpha (Capella). Congratulations on finding M38 under the moonlight! We’ll look again at this superb open cluster under darker skies.

May all your journeys be at light speed… ~Tammy Plotner. Additional writing by Jeff Barbour @ astro.geekjoy.com

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

M1: “The Crab Nebula”. Image credit: R. Jay GaBany. Click to enlarge.
Monday, January 23 – Thanks to dark skies, tonight will be the perfect opportunity to “go crabbing” in Taurus. Although M1 was discovered by John Bevis in 1731, it became the first object on Charles Messier’s astronomical list. He rediscovered M1 while searching for the expected return of Halley’s Comet in late August 1758 and these “comet confusions” prompted Messier to start cataloging. It wasn’t until Lord Rosse gathered enough light from M1 in the mid-1840’s that the faint filamentary structure was noted (although he may not have given the Crab Nebula its name). To have a look for yourself, locate Zeta Tauri and look about a finger-width northwest. You won’t see the “Crab legs” in small scopes – but there’s much more to learn about this famous “supernova remnant” in the future.

Tuesday, January 24 – Today is the birthday of American solar astronomer Harold Babcock. Born in 1882, Babcock proposed that the sunspot cycle was a result of the Sun’s differential rotation and magnetic field in 1961. Would you like to have a look at the Sun? Although solar observing is best done with a proper filter, it is perfectly safe to use the “solar projection method.”

Before we start, NEVER look at the Sun directly with the eye or with any unfiltered optical device, such as binoculars or a telescope. We’re not joking when we say this will blind you. Exposed film, mylar, and smoked glass are also UNSAFE. But don’t be afraid, because we’re here to tell you how you can enjoy solar viewing. A safe way to observe sunspots is to “project” an image of the Sun through a telescope or binoculars onto a screen. This can be as simple as cardboard, a paper plate, a wall or whatever you have handy. If you’re using a telescope be sure the finderscope is securely capped. If you use binoculars, cover one of the two tubes. By using the shadow method to aim, you will see a bright circle of light on your makeshift screen. This is the solar disc. Adjust the focus by moving the distance of the screen from your optics until it’s about the size of a small plate. If the image is blurry, use manual focus until the edges of the disc become sharp. Even though it might take a little practice, you’ll soon become proficient at this method and be able to see a surprising amount of detail in and around sunspot areas. Happy and SAFE viewing to you!

Today in 1986, the United States Voyager 2 became the first spacecraft to fly by Uranus, providing us with the most outstanding photographs and information on the planet to date. After 10,382 days of successful operation, Voyager 2 still continues on towards the stars carrying “The Sounds of Earth.”

Speaking of stars, turn your scope on brilliant Rigel – Orion’s south-westernmost bright star. Enjoy its cool radiance and look for an 8th magnitude companion just outside the spikes of light caused by the Earth’s atmosphere.

Wednesday, January 25 – This morning before dawn, look for the Moon very near Antares. Many observers in the southern portions of Mexico, Peru and Ecudor will have the opportunity to see it occulted, so please check with the International Occultation Timing Association (IOTA) for details.

Today is the birthday of Joseph Louis Lagrange. Born in 1736, the famed French mathematician made important contributions to the field of celestial mechanics. We’re not talking “wrenches in space,” but how masses interact gravitationally to keep things orderly in the solar system and beyond. If you’re up early this morning, have a look at the lunar crater named for him. You’ll find LaGrange on the southern limb about one-quarter the distance up from the cusp. But, you won’t find the SOHO satellite there. NASA’s “eye on Sol” is parked at Lagrange point one (L1) between the Earth and Sun.

Tonight let’s journey to Orion and have a look at a pair of neighboring open clusters. Found a little less than a hand span northwest of Betelguese, NGC 1807 and NGC 1817 aren’t exactly twins. Both clusters are of similar magnitude and can be seen as faint patches in binoculars. Through a telescope, NGC 1817 appears far more populated with stars than its neighbor. Studies based on stellar motion reveal that NGC 1817 has far more stars than the brighter NGC 1807. Although the two are quite distant from one another in space, we get to see them both as close friends…

Thursday, January 26 – In keeping with our dark sky studies, tonight we’ll explore planetary nebula NGC 1514 in Taurus. Locate it by moving about two finger-width’s south-east of Zeta Perseii. Planetary nebulae were first described as “planetary” by William Herschel in 1785. Before then, all were simply considered “nebulae.” It was once thought they were made of stars, but today we know planetaries are created from material given off by a single star. Many show well-defined rings of one type or another. Others – like M1 – are irregularly shaped supernova remnants. NGC 1514’s material is slowly boiled off over time, rather than caused by a violent explosion.

It would be very hard to find the neutron central star in M1, but almost any scope can make out NGC 1514’s 10th magnitude fueling star as it quietly cooks away gases to feed its nebulous shroud. Because it is so bright, it can easily overwhelm the eye. This makes NGC 1514 similar to the famous “Blinking Planetary” – NGC 6826 – in Cygnus.

Friday, January 27 – The planet Saturn is at opposition tonight, meaning it rises as the Sun sets. Look for it late in the evening moving past M44 – “the Beehive” – cluster in Cancer. The 2006 apparition will continue to feature Saturn’s rings and the planet’s southern hemisphere.

Are you ready for more deep sky? Then let’s head off towards the galaxy NGC 1023 in Perseus. It’s a beautiful example of a slightly tilted “SB0” spiral galaxy. You won’t see any spiral arms on this one – but not because your telescope isn’t large enough. Unlike our own Milky Way, NGC 1023 really doesn’t have any. But, it does have a bright galactic hub bending like a thick lens going outward. At the center of the hub is one of the most massive black holes within a hundred million light-years. Don’t worry about being pulled in, because this galaxy is located 33 million light-years away! You’ll find it a bit closer to home about a fist-width southwest of Algol – Beta Persei.

There is a much closer supermassive black hole at the center of our own galaxy. It’s a profound gravitational anomaly causing stars to take on strange, highly elliptical orbits at very high speeds – some which have orbits taking far less time than Jupiter does to revolve around the Sun. The stars involved (“S-stars”) appear mysteriously young to astronomers. This might occur because their outer atmospheres are being stripped away by gravitational tidal forces. It’s happening in NGC 1023 as well, but that galaxy is ten times more massive than our own!

Saturday, January 28 – It’s Saturday and New Moon! Many amateurs will be out tonight “partying” beneath the darkest night sky of the month. All that’s needed is a wide-open field well away from glow from artificial lights and a variety of optical instruments – eyes, binoculars, and telescopes. The joy of observing can be multiplied many times over when shared with others!

What should you bring to a “star party?” Start with your favorite scope and a short list of things to observe including both “everybody’s favorites” and at least one “special study” that others may not have observed before! Tonight, the two “Greats” – M31 and M42 – will be on everyone’s list, but what about those “great” unknowns?

Consider NGC 1535 – a fine planetary nebula with central star in Eridanus. At magnitude 10, this 1600 light-year distant beauty has an easy 12th magnitude star providing illumination at its core. Use high power to give “image scale” to this small, subtle study. You’ll find it just about a fist’s width east-northeast of Gamma Eridani. If you find it difficult, you’d be right – but that’s why this aqua blue planetary is not more widely appreciated!

Sunday, January 29 – Today is the birthday of Johannes Hevelius. Born in 1611, Hevelius was the first to publish detailed maps of the Moon. His book, Selenographia, debuted in 1647. That’s 359 years ago – and it’s still accurate! Too bad there’s no Moon to celebrate with… Or is it?

Let’s have a look instead at the Pleiades – M45. We aren’t finished observing the Pleiades yet, because the “Seven Sisters” may not be finished either. On a moonless night, you can see the afterbirth of stellar creation – the faint sheen of nebulosity illuminated by hot stars doing their best to “light up the night.” Most easily spotted is NGC 1435 associated with Merope and NGC 1432 near Maia. To be sure you are seeing the nebulosity, look well away from both stars. From Merope (the southernmost bright star) look due south – away from the brightest stars of the cluster. Compare that to the nebulosity which surrounds all seven major stars – but especially Maia – north of Merope. Be sure not to stare directly. They will appear like a pale smear or a “fog” on your optics. Move your eyes around to activate the sensitive light-receptors in the eye – that’s using your eyes to advantage!

Until next week? May all of your journeys be at… Light Speed! ~Tammy Plotner

Contributing Writer: Jeff Barbour @ astro.geekjoy.com

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

M44. Image credit: NOAO/AURA/NSF. Click to enlarge.
Monday, January 16 – Although the early rise of tonight’s Moon will hamper the Delta Cancrid meteor shower, be on the lookout for fast moving meteors appearing to radiate from an area just west of the “Beehive” – M44. It’s a minor shower, with a fall rate of about 4 per hour, but it’s fun to catch one!

While we’re watching, take a look at M44 with binoculars or a low power telescope. You’ll find it in the center of the triangle of bright stars, Pollux, Regulus, and Procyon, and it is usually visible to the unaided eye from dark sky locations. Better known as the “Beehive,” M44 shows several dozen stars through binoculars. Through the scope, the cluster reveals up to 100 stars! Of the 400 known members, most congregate in an elliptical “swarm” spanning 15 light-years. The “Beehive” is only slightly more distant than the Pleiades at 500 light-years away. Thanks to its advanced stellar evolution, it contains several red giants, leading astronomers to believe it is around 400 million years old.

After moonrise, have a look at the lunar surface as the terminator reaches the edge of Mare Crisium in the northeastern quarter. Depending on your viewing time, you may have the opportunity to spot small craters Alhazen and Hansen on its eastern edge. Look for a long “wrinkle” creasing Crisium’s smooth sands. Such lunar features are known as dorsae. Dorsa Tetyaev and Dorsa Harker come together along Mare Crisium’s eastern shore. Look for south-central Dorsa Termier and Dorsum Oppel along Crisium’s west bank. These frozen “waves” of lava are millions of years old.

Tuesday, January 17 – With time to spare before Moon rise tonight, let’s hunt down that “wascally wabbit” Lepus and have a look at M79. Let Alpha and Beta be your guide as you drop the same distance between them to the south for double star ADS3954 and this cool little globular cluster.

Discovered by Pierre M?chain in 1780, M79 is not large, nor bright, but is visible in binoculars. Large telescopes will find it well resolved with a rich core area. Around 50,000 light-years away, this particular globular is very low in variables and recedes from us at a “rabbit” speed of 118 miles per second. But, don’t worry – it will remain visible for a very long time!

Now, take a quick look at tonight’s Moon. The terminator has advanced through Mare Crisium and looks like a gigantic “bite” taken out of the lunar edge.

Wednesday, January 18 – If you are up before dawn, why not spend a moment looking at the sky? Although the Moon will still be bright, stay on watch for meteors belonging to the Coma Berenicid shower. The fall rate is very modest with only one or two per hour, but these are among the very fastest meteors known. Blazing through the atmosphere at 65 kilometers per second, the trails will point back to the Coma Berenices star cluster east of Leo.

Since we’ll have early dark skies, let’s have a look at a single star – R Leporis. Because it is variable, ranging in magnitude from 5.5 to 11.7, R may or may not be visible to the unaided eye tonight. Use a telescope, or binoculars, to locate it west of Mu. Look for a line of three dim stars and choose the centermost.

Most commonly known as “Hind’s Crimson Star,” this long term, pulsating red variable was discovered in 1845 by J.R. Hind. Its light changes by a factor of 250 times during its period of 432 days, but R Leporis can sometimes stall while brightening. As an old red star, R takes on a unique ruby-red color as it dims. To understand carbon stars, picture a kerosene lamp burning with its wick up high. This “high burn” causes the glass to smoke, dimming the light and changing the color. Although this example is simplistic, it hints at how carbon stars work. When it sloughs off the soot? It brightens again!

“Hind’s Crimson Star” is believed to be about 1500 light-years distant and moving slowing away from us at about 32 km per second. No matter how “bright” you find it tonight, its unusually deep red color makes it a true pleasure.

Thursday, January 19 – Johann Bode was born today in 1747. Bode publicized the Titus-Bode law, a nearly geometric progression of the distances of the planets from the Sun, and made a number of discoveries of deepsky studies objects. Also born today in 1851, was Jacobus Kapteyn. Kapteyn studied the distribution and motion of almost half a million stars and created the first modern model of the size and structure of the Milky Way Galaxy.

Tonight in celebration of them both, let’s have a first look at a pair of circumpolar galaxies known as “Bode’s Nebulae.” Discovered by Johann in 1774, the galaxies known as M81 and M82 were first described by him as “nebulous.” In Bode’s time, it was thought such patches were solar systems in formation, but by Kapteyn’s time in the late 1800’s, astronomers were beginning understand the mechanics of stellar motion in the Milky Way galaxy. While M81 and M82 are not in good sky position right now, you can still track them down in binoculars. Look for the bowl of the “Big Dipper” and draw an imaginary line from Phecda to Dubhe (the southeastern and northwestern stars) and extend it the same distance northwest. Fade ever so slightly toward Polaris and enjoy this bright pair of island universes sharing space in the night.

Friday, January 20 – Born this day in 1573 was Simon Mayr. Although Mayr’s name is not widely recognized, we know the names he has given to Jupiter’s satellites. During 1609 and 1610, Mayr was observing moons of Jupiter at about the same time as Galileo. Though discovery was credited to Galileo, Mayr was given the honor of naming them. If you’re up before dawn, look for Jupiter in the constellation Libra and see if you can spot Io, Ganymede, Callisto and Europa for yourself!

Early dark skies mean a chance for serious study, and tonight our target will be a challenge. Head towards Zeta Ceti and neighboring Chi Ceti. When you’ve identified Chi, power up and look north-northwest to locate small, 11.8 magnitude galaxy NGC 681. It might be small and faint, but it’s a great example of barred spiral seen near edge-on. Mid-sized scopes will see little detail, but large instruments reveal a broad equatorial dust lane. At a distance of 55 million light-years, this peculiar galaxy is a rare sight. All its stars move at the same orbital speed around the core – hinting at vast quantities of unseen, mysterious “dark matter!”

Saturday, January 21 – John Couch Adams was born today in 1792. Adams, along with Urbain Le Verrier, mathematically predicted the existence of Neptune. Also born today in 1908 was Bengt Stromgren – developer of the theory of ionization nebulae (H II regions). Tonight we’ll take a look at an ionization nebula as we return for a more in-depth look at M42.

Known as “The Great Orion Nebula,” let’s learn what makes it glow. M42 is a great cloud of gas spanning more than 20,000 times the size of our own solar system and its light is mainly florescent. For most observers, it appears to have a slight greenish color – caused by oxygen being stripped of electrons by radiation from nearby stars. At the heart of this immense region is an area known as the “Trapezium” – its four brightest stars form perhaps the most celebrated multiple star system in the night sky. The Trapezium itself belongs to a faint cluster of stars now approaching main sequence and resides in an area of the nebula known as the “Huygenian Region” (named after 17th century astronomer and optician Christian Huygens who first observed it in detail).

Buried amidst the bright ribbons and curls of this cloud of predominately hydrogen gas are many star forming regions. Appearing like “knots,” these Herbig-Haro objects are thought to be stars in the earliest stages of condensation. Associated with these objects are a great number of faint red stars and erratically luminous variables – young stars, possibly of the T Tauri type. There are also “flare stars,” whose rapid variations in brightness mean an ever changing view.

While studying M42, you’ll note the apparent turbulence of the area – and with good reason. The “Great Nebula’s” many different regions move at varying speeds. The rate of expansion at the outer edges may be caused by radiation from the very youngest stars present. Although M42 may have been luminous for as long as 23,000 years, it is possible that new stars are still forming, while others were ejected by gravitation. Known as “runaway” stars, we’ll look at these strange members later in detail. A tremendous X-ray source (2U0525-06) is quite near the Trapezium and hints at the possibility of a black hole present within M42!

Sunday, January 22 – With tonight’s dark skies let’s have a look at another “cloud in space” – M78. It is easily located around two finger-widths north-northeast of Alnitak. Despite being 8th magnitude, you’ll probably need a telescope to see it. M78 is actually a bright outcropping of an extended region of nebulosity (the Orion Complex) including M42, 43, NGC 1975-77-79, the Flame Nebula, and the Horsehead. There’s plenty of material for future starbirth here! Nicknamed “Casper the Friendly Ghost Nebula,” M78 was discovered by Pierre Mechain in 1780. It shines almost purely by reflection and is the brightest non-emission nebula observable by amateurs. For larger scopes, look at nearby nebula NGC 2071. Unlike M78, NGC 2071 is associated with a single 10th magnitude star instead of the pair that gives “Casper” his glowing eyes.

Thank you again to all the kind folks who have responded to “365 Days of SkyWatching”! May all your journeys be at light speed… ~Tammy Plotner.

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

Plato crater on the Moon. Image credit: Wes Higgins. Click to enlarge.
Monday, January 9 – Today in 1839, South African Thomas Henderson measured the distance to the closest bright star other than the Sun. Using geometrical parallax, Alpha Centauri was found to be 4.3 light-years away – this amounted to a distance of almost 41 trillion kilometers! Such a distance is the equivalent of over 270,000 earth-sun distances (astronomical units – AU).

Speaking of parallax, let’s take a look at a star with the precisely measured distance of 10.67 light-years from our Sun – Epsilon Eridani. Epsilon is the third closest of the visible stars and can be found tonight by starting at Rigel. About a hand span southwest, locate Gamma Eridani and head another fist-width northwest for a pair of easy stars. Epsilon is the westernmost.

At magnitude 3.7, Epsilon is not one of the brightest stars in the night sky because it has only 85% of the mass of our own Sun. It is also a young star, some 4 billion years younger than Sol and slightly variable. But, like our own “star,” Epsilon has no companion. On a curious note, science fiction chose Epsilon Eridani to be the home of the Vulcans!
Now let’s have a look at the Moon and a crater so prominent that it can be spotted unaided. To the lunar north, look for the dark ellipse of Plato. This mountain-walled plain with a dark floor is a Class V crater. Its slightly oval shape spans 64 by 67 miles in diameter, but appears far more elliptical due to its northern latitude. Plato’s floor is its most curious feature. Consisting of 2,700 square miles of unique lava, and only broken by a couple of very minor and supremely challenging craters, Plato is one of the very few areas on the lunar surface that seems to have changed in recent history.

Be sure to notice how close the Moon and Pleiades are tonight and check on the internet (IOTA) for grazing and occultation events visible from your area.

Tuesday, January 10 – Robert W. Wilson was born this day in 1936. Wilson is co-discoverer, along with Arno Penzias, of the cosmic microwave background and in 1978, won the Nobel Prize for Physics. On this day in 1946, the US Army’s Signal Corps became the first to successfully bounce radar waves off the Moon. Although this might sound like a minor achievement, let’s look just a bit further into what it really meant.

Known as “Project Diana,” scientists were hard at work to find a way to pierce the Earth’s ionosphere with radio waves – a feat believed impossible at the time. Headed by Lt. Col. John DeWitt, and working with only a handful of full-time researchers, a modified bedspring-type radar antenna was set up at Camp Evans, Georgia. Anxiously, the power was cranked up and the antenna aimed at the rising Moon. A series of radar signals were broadcast and echoes were picked up exactly 2.5 seconds later – the time it takes light to travel to the Moon and back. The significance of Project Diana cannot be underestimated. Because the ionosphere could be pierced, communications became possible between Earth and future space missions. Although it would be more than a decade before the first satellites and manned missions were launched into space, Project Diana had paved the way.

To commemorate Project Diana, let’s have a look at one of the most impressive craters on the Moon – Copernicus.
While Copernicus is not the oldest, deepest, largest, or brightest crater on the Moon, it certainly is one of the most detailed. Visible in binoculars toward Plato and near the terminator, this youthful crater gives a highly etched appearance. Its location in a fairly smooth plain near the center of the Moon’s disc, and prominent “splash” ray system, all combine to make Copernicus visually stunning in a small telescope.
Tonight let’s try our hand at splitting a double star – Gamma Arietis. Known as Mesarthim, Gamma is the third star in the line of bright stars – about a hand span west of the Pleiades – pointing in the direction of Eta Piscium. This orange and green pair gives the appearance of two glowing eyes in the night. Seeing two equal magnitude stars so close together can’t help but get you out observing – even when there’s Moon!

Wednesday, January 11 – Tonight in 1787, Sir William Herschel discovered Uranus’ largest moons – Oberon and Titania. Let’s have a look. Sixth magnitude Uranus is around two finder-widths south-southwest of Lambda Aquarii. Its small, pale blue disc will be distinguishable from neighboring stars. Under the right conditions, the planet can sometimes be seen unaided and was once given the designation “34 Tauri” by 17th century astronomer John Flamsteed. The two satellites – both 14th magnitude – can be seen with very large scopes with excellent seeing conditions.

The most outstanding feature on the northern lunar surface this evening is the “Bay of Rainbows” – Sinus Iridum. Take the time to power up and enjoy its many wonderful features including the bright Promontorium LaPlace to the northeast and Heraclides to the southwest. Ringed by the Juras Mountains, Sinus Iridum also includes crater Bianchini at center and Sharp to the west.

Thursday, January 12 – This date celebrates the 1830 founding of what – one year later – would become the Royal Astronomical Society. Conceived by John Herschel, Charles Babbage, James South and others, the RAS has continuously published its Monthly Notices since 1831.

Tonight our primary lunar study is crater Kepler. Look for it as a bright point, slightly lunar north of center near the terminator. Its home is the Oceanus Procellarum – a sprawling dark mare composed primarily of dark minerals of low reflectivity (albedo) such as iron and magnesium. Bright, young Kepler will display a wonderfully developed ray system. The crater rim is very bright, consisting mostly of a pale rock called anorthosite. The “lines” extending from Kepler are fragments that were splashed out and flung across the lunar surface when the impact occurred. The region is also home to features known as “domes” – seen between the crater and the Carpathian Mountains. So unique is Kepler’s geological formation that it became the first crater mapped by U.S. Geological Survey in 1962.

With the nearly full Moon in Gemini, go north to Cassiopeia and check out wide double star 35 Cassiopeia about two finger-widths west of Epsilon and an equal distance north of Gamma. This is an easy split for telescopes and can be resolved in steady binoculars.

Friday, January 13 – Tonight let’s give the Moon a rest and turn our scopes to Mars high overhead. With the exception of Sirius, Mars remains brighter than any star in the sky. To the eye, the planet’s ruddy glow makes it unmistakable. Through the telescope, observers can make out large-scale details such as the planets polar caps, Syrtis Major, Sinus Sabaeus, and the three major Mares – Cimmerium, Sirenum and Acidalium. Although good “seeing” makes high power and fine details possible, sometimes just “viewing” is half the fun!

Saturday, January 14 – Tonight’s Full Moon is known as the Wolf Moon. For the northern hemisphere in January, extreme cold and deep snows gave rise to the legend of wolf packs howling hungrily outside Indian villages. Sometimes the January Full Moon is also referred to as the Old Moon, or the Moon after Yule. No matter what it is called, it is still a lovely sight to watch rise and glide across the luminous night sky.

As a challenge this evening, try tracking down 5th magnitude double star Zeta Piscium. Located two finger-widths due east of Epsilon, this pair is easily resolved at low magnification due to its near matched brightness. Look for subtle shades of color displayed by the blue primary, and ivory-colored secondary.

Sunday, January 15 – With only short time before the Moon rises tonight, let’s start our evening by viewing a distant multiple star system – Sigma Orionis.

You’ll easily find 1400 light-years distant Sigma less than a finger-width below the left hand star in Orion’s “Belt” (Zeta or Alnitak). What won’t be easy is to distinguish the closest and brightest pair! 3.8 magnitude A and 6.6 magnitude B revolve around each other every 170 years and are separated by a close 0.3 arc seconds. Among the most massive binaries known, these two stars have extremely hot surfaces (approaching 50,000 degrees K) and both appear white in the eyepiece.

At a more comfortable separation, the white 8.8 magnitude C star resides 11.4 arc seconds southwest of the brighter pair. At a similar distance from AB to the east, look for red 6.7 magnitude D. Considerably further away at 41 arc seconds, the blue E star resides east-northeast of the AB primary. Unusual star E shares the same spectral qualities as the AB primary, yet is rich in helium light (emission lines) within its color spectrum. If five isn’t enough, then look 30 arc seconds southwest of E – because it, too, has a companion. All of these stars are part of the same physical system spanning about one-third of a light-year.

If you choose to look at the lunar surface, carefully check along the eastern edge where the terminator is now receding. In the north, look for the dark shades of Mare Humboldtianum and the equally dark floor of crater Endymion to its west. This lava filled area is around 70 miles in diameter.

I would personally like to thank all of you for your support and kind comments on the look at the year ahead. Be sure to stay tuned to the weekly column as breaking observing news is added. Until next week, ask for the Moon, but keep reaching for the stars! May all of your journeys be at light speed… ~Tammy Plotner