Tammy Plotner, Author at Universe Today

March 21, 2009December 24, 2015 by Tammy Plotner

Meteor Shower Alert on March 22! Camelopardalids and March Geminids Arrive…

On Sunday, March 22, two meteor showers will grace the dark evening sky – the Camelopardalids and March Geminids. Would you like to learn more about what makes them special and why? Then let’s head out into the dark…

We’ll start first with the Camelopardalids. These have no definite peak, and a screaming fall rate of only one per hour. They do have a claim to fame however – these are the slowest meteors known – arriving at a speed of only 7 kilometers per second and activity has been historically recorded on this date. Any bright streaks you might see belonging to the Camelopardalids will appear to emanate from the north. While this might seem rather boring, any member of the Camelopardalids you might spot are anything but boring. “A search for parent bodies for 22 short-period meteoroid streams with an account of long-period planetary perturbations was carried out. Five minor body complexes are found among short-period comets, Earth-crossing asteroids and meteoroid streams.” say Y.V. Obrubov, “There are ten members in the major complex : two comets, P/Schwassmann-Wachmann 3 and P/Pons-Winnecke ; four asteroids, 1984 KD (3671), 4788 PL, 1987 SJ3, 1987 PA…” So where does the stream for the Camelopardalids fit in? Try possibly asteroid Amor (1221) and/or asteroid Selevk (3288) as part of Complex 5.

1221 Amor is the namesake of the Amor asteroids – a group of near-Earth asteroids whose orbits range between those of Earth and Mars. Amor-types often cross Mars orbital path, but not Earth’s. However, on March 12, 1932, Belgian astronomer Eugene Delporte photographed Amor as it approached Earth to within 16 million kilometers (about 40 times the distance from Earth to the Moon). This was the first time an asteroid was witnessed so close to Earth and became our virtual wake-up call to potential hazards. Not surpising, 3288 Selevk is also a planet crossing asteroid, too. According to Obrubov’s research there are 22 meteoroid swarms from bodies with orbital period of less than six years that could account for up to 104 meteor showers – 72 of which have been confirmed either photographically or by radar. “The Camelopardalids has a twin – the Gamma Aurigids.” says Obrubov, “We may therefore assume that the remnants of the parent bodies have been found for two more meteor showers. The existence of complexes of minor bodies again raises the question of the possibility of the simultaneous existence of active comets and products of disintegration – meteoroid swarms and possibly asteroids of the Apollo, Amor and Aten groups…”

So, now we have meteors possibly coming from an asteroid, but what about the other meteor shower that occurs tonight? That’s right… the March Geminids. These were first discovered and recorded in 1973, then confirmed in 1975. With a much improved fall rate of up to 40 per hour, these slightly faster meteors will greatly increase your chance of spotting a shooting star. Like the Camelopardalids, the March Geminds are slower than average – but what causes them? Let’s turn to the work of Miroslav Plavec for an answer:

“In 1947, Whipple published new elements of the Geminid meteor shower, obtained photographically. An extremely short period, 1.65 years, moderate inclination and considerable eccentricity together make the orbit of this shower an extraordinary one both in comparison with comets and with minor planets. But, according to Hoffmeister, the existence of similar meteor showers seems to be indicated. Such a short-period meteor shower as the Geminids presents new aspects in meteor astronomy. Planetary perturbations are likely to play a great part in its nature. The study of secular perturbations is especially important, both in investigating the connection with comets, and also from the observer’s point of view; for example, Adams’ classical work on the Leonids.”

So, when do you start watching? Just as soon as the sky is good and dark at your local time. Use your own best judgement on where to loosely face based on the position of both Camelopardalis and Gemini at the time of your observation. (For most northern hemisphere locations, I would simply suggest facing roughly north and focusing your attention overhead.) Grab a friend, a blanket, a thermos… take your notes and a timepiece, too.

You can make an important contribution by observing when possible. Since the shower wasn’t reported until 1973 and confirmed by a high rate of activity 2 years later, scientists aren’t really sure if the Earth had passed through that particular particle stream until that time. By observing and reporting, even to sources like Universe Today, you are providing an invaluable Internet record to help determine if the stream is genuine. It the March Geminids truly are a viable annual shower, this trail might lead to an undiscovered comet.

If you wish to report your findings elsewhere, please visit the Association of Lunar and Planetary Observers (ALPO) and locate the meteor observing tab. In these pages you will also find links to information from the North American Meteor Network (NAMN), and other things to assist you like charts to understand the meteor’s magnitude, the limiting magnitude of your location, and details for recording what you see and how to fill out an observation report. While it’s certainly true you may see absolutely nothing during an hour of observing, negative observations are also important. This helps to establish if the March Geminids should be considered an annual shower or not. You may also just happen to step outside at the right time and see a flurry of activity as well. Just remember…

When opportunity knocks, you’ve got to be there to open the door!

March 20, 2009December 24, 2015 by Tammy Plotner

SkyWatcher’s Forecast: March 20-26, 2009 – A Messier Marathon Special Edition!

Greetings, fellow SkyWatchers! That’s right… It’s that time again. Equinox and upcoming New Moon means that many of us are going to try and kill ourselves to capture all 110 Messier Catalog objects in just one night. When I was a much younger lass, I used to think that was fun. Now that I’m considerably older and have to pay a physical price for staying outside all night in the cold? Well… It’s not quite as appealing as it used to be. But, I ain’t ready for the dirt nap just yet. If you think you’ve still got what it takes, then follow me…

Friday, March 20, 2009 – Since the beginning of the year, the Sun has been traveling low in the sky, moving higher each day until reaching northern hemisphere vernal equinox. Today the Sun will rise exactly in the east and set exactly in the west – precisely 12 hours later – making it possible for most observers to see all 110 Messier objects in a single night. The Messier Marathon isn’t easy. This year,why not try your own style of marathoning, as we take a less frenzied pace over the next 11 days, enjoying these splendid objects ‘‘ten at a time.’’

When the sky darkens enough to find guidestar Delta Ceti, the M77 (RA 02 42 40.83 Dec -00 00 48.4) spiral galaxy will be your first and the M74 (RA 01 36 41.84 Dec +15 46 59.6) spiral galaxy east of Eta Pisces will be your second mark. Both are telescopic only, and an extreme challenge due to low position. Next is M33, west of Alpha Triangulum. With ideal skies, the Pinwheel Galaxy can be seen in binoculars, but sky glow makes this huge, low-surface brightness spiral difficult for even telescopes at low power. M31 (RA 00 42 44.31 Dec +41 16 09.4), the Andromeda Galaxy, is a delightful capture for both binoculars and scopes just west of Nu Andromedae. For the telescope, two more on the list are companions to M31: elliptical M32 (RA 00 42 41.87 Dec +40 51 57.2) on its southeastern edge, and M110 (RA 00 40 22.00 Dec +41 41 07.0), to the northwest.

Head northwest for two open clusters visible to both telescopes and binoculars. You’ll find M52 (RA 23 24 48.00 Dec +61 35 -0.0) easiest by identifying Alpha and Beta Cassiopeiae, drawing a mental line between them, and extending it the same distance northwest of Beta. Next, hop north of Delta Cassiopeiae to pick up our eighth object—open cluster M103 (RA 01 33 24.00 Dec +60 39 00.0). Head south toward Perseus to telescopically locate the M76 (RA 01 42 19.95 Dec +51 34 31.1) planetary nebula just north of Phi. Binoculars are all that’s needed to see M34, an open cluster located roughly halfway between Algol and the lovely double Almach. As you can see, such a quick journey takes away some of the beauty of learning the history and science behind the objects… But the race is on!

Saturday, March 21, 2009 – Today, note the 1927 birth on this date of Halton Christian Arp, one of the most noted minds of our time regarding the origin and evolution of galaxies. Through his incredible study of peculiar galaxies and quasars, we are no longer able to assume that redshift is a uniform indicator of distance, or that the two are unrelated.

Tonight our marathon will be more relaxed because the fastest-setting objects are already completed. Take a moment to enjoy M45 (RA 03 47 24.00 Dec +24 07 00.0), the Pleiades. The ‘‘Seven Sisters’’ are easily visible high in the west, and their cool, blue beauty is incomparable in binoculars or telescopes. Head for Lepus and identify Beta and Epsilon. Triangulating south with this pair is 5th-magnitude star ADS3954, and the small globular M79 (RA 05 24 10.59 Dec -24 31 27.3) to its northeast. M42 (RA 05 35 17.30 Dec -05 23 28.0) , the Orion Nebula, is next. M43 (RA 05 35 31.00 Dec -05 16 12.0) is part of M42 to the north northeast. The next two objects are M78 (RA 05 46 46.70 Dec +00 00 50.0), northeast of Zeta Orionis and M1 (RA 05 34 31.97 Dec +22 00 52.1), the Crab Nebula, northwest of Zeta Tauri.

Now take a few minutes to relax. The remaining objects on tonight’s list are all very easy, well positioned, and observable with binoculars. Are you ready? Then let’s go! Open cluster M35 (RA 06 09 06.00 Dec +24 21 00.0) is northwest of the toe of Gemini – Eta. The next stop is Auriga, directly between Theta and southern Beta. Slightly to the east you’ll find open cluster M37 (RA 05 52 19.00 Dec +32 33 12.0). Now use Theta and western Iota. Roughly halfway between them and in the center of Auriga you will find open cluster M38 (RA 05 28 43.00 Dec +35 51 18.0). Hop southeast to capture M36 (RA 05 36 12.00 Dec +34 08 24.0).

Although this pace may seem rather scandalous, take stock of what you’ve accomplished! You’ve visited 20 Messier objects in just two nights. . .with time to spare. Return to your favorite objects and enjoy them. As Halton Arp once said:

“Sometimes I think that Astronomy is not so much a science as a series of scandals.”

Sunday, March 22, 2009 – Born on this date in 1394 was Ulugh Beg, builder of the first observatory. Beg’s chart listed 994 stars and was the first produced since Hipparchus! In 1799, Friedrich Wilhelm August Argelander, who cataloged the positions and magnitudes of 324,188 variable stars, was born!

Now get Sirius, go south, and start our list for tonight with open cluster M41. Return to Sirius and head a fist-width east/northeast for M47 (RA 07 36 36.00 Dec -14 29 -0.0). Dimmer, more compressed M46 (RA 07 41 42.00 Dec -14 49 00.0) is east. Drop slowly south about three fingerwidths and encounter lively M93 (RA 07 44 36.00 Dec -23 52 00.0)! Incredibly colorful open cluster M50 (RA 07 02 40.47 Dec -08 21 50.5) is roughly one-third the distance between Sirius and Procyon. Drop south-southeast of Zeta Monocerotis for dim open cluster M48 (RA 08 13 42.00 Dec -05 45 00.0). The ‘‘Beehive’’ – M44 (RA 08 40 24.00 Dec +19 41 -0.0) – is just north-northwest of Delta Cancri. Continue south to Alpha, and then west for M67 (RA 08 51 18.00 Dec +11 48 00.0). It will appear as a fine haze to binoculars, but telescopes see a spectacular cloud of similar magnitude resolvable stars.

Telescopes, head a fist-width east Regulus for finderscope stars 52 and 53, and head between them. Just about 1.5 degrees south of 52 is elliptical galaxy M105 (RA 10 47 49.60 Dec +12 34 53.9). Larger scopes see two additional faint galaxies, NGC 3384 and NGC 3389, to M105’s west. Continue another degree south toward star 53 for the silver-gray beauty of M96 (RA 10 46 45.78 Dec +11 49 10.2). Enjoy its bright nucleus and wispy arms!

Now relax and enjoy a spring evening with two meteor showers. The northern hemisphere Camelopardalids have no definite peak, and a fall rate of only 1 per hour. They’re the slowest recorded meteors, entering our atmosphere at speeds of only 7 kilometers per second! Far more interesting for both hemispheres is tonight’s peak of the March Geminids. These slower than normal meteors will be fun to watch! When you see a bright streak, trace it back to its point of origin: which did you see, a Camelopardalid, or a March Geminid?

Monday, March 23, 2009 – In 2001 on this date the Mir space station ended 15 years in orbit with a fiery return. This date is also the 1837 birth of Richard Anthony Proctor who showed the stars’ motion, distribution, and relation to nebulae. In 1829, Norman Pogson, creator of the magnitude scale still used today, was born. The year 1749 saw the birth of Pierre-Simon Laplace, who theorized that the Solar System formed from a nebula, formulated mathematical probability, and helped create the metric system!

Return to Leo tonight. Identify 52 Leonis and drop south past M105 for M95 (RA 10 43 57.70 Dec +11 42 13.7), which isn’t as bright or large as neighboring M96 (RA 10 46 45.78 Dec +11 49 10.2). Small scopes see central brightening, and large ones begin resolution of this awesome barred spiral. Look to the southwestern star of the three marking Leo’s hips – Theta Leonis. South is faint star 73, and a degree east-southeast is the pairing of M65 and M66. Western M65 (RA 11 18 55.78 Dec +13 05 32.3) and eastern M66 (RA 11 20 15.07 Dec +12 59 21.6) are both beautiful spirals worthy of far more time and attention. Head north for another same-field pair – M81 and M82 – in Ursa Major. Draw a mental line between Gamma and Alpha. Extend the line beyond Alpha the same distance. Begin an eyepiece sweep to locate them. The southernmost is stunning, bright-cored M81 (RA 09 55 33.17 Dec +69 03 55.1). North is the broken, spindle-shaped peculiar galaxy M82 (RA 09 55 52.19 Dec +69 40 48.8). Southeast of Beta Ursae Majoris (UM) is the edge-on galaxy M108 (RA 11 11 31.29 Dec +55 40 31.0).

Continue another half degree southeast for the Jupiter-sized planetary M97 (RA 11 14 47.73 Dec +55 01 08.5). Continue south to Gamma UM for same-field M109 (RA 11 57 35.90 Dec +53 22 35.0). The last in Ursa Major is an error on Messier’s part. M40 (RA 12 22 24.00 Dec +58 05 -0.0) is actually double star WNC4, located northeast of 70 Ursae Majoris. Now to Canes Venatici and our last object tonight: Alpha and northern Beta are easily recognizable to the east of the last star in the handle of the Big Dipper (Eta). You’ll find the soft-spoken spiral galaxy M106 (RA 12 18 57.54 Dec +47 18 14.3) almost directly midway between Beta CVn and Gamma UM less than 2 degrees south of star 3. Add as much aperture as you can to this gorgeous study!

Tuesday, March 24, 2009 – On this date in 1835 Josef Stefan was born, a physicist whose word was ‘‘law’’ to radiation! In 1941 on this date, Joseph Taylor, Jr, the radio astronomer who jointly discovered the first binary pulsar, was born. Last, let’s celebrate the 1893 birth of Walter Baade, who studied the Andromeda Galaxy’s core with the 100’’ Hooker telescope, resolving it (and two different Cepheids) for the first time.

Tonight, identify Canes Venatici’s two brightest stars, Alpha and Beta. Galaxy M94 (RA 12 50 52.63 Dec +41 07 09.3) forms a triangle with Alpha and Beta CnV, the apex toward Eta Ursae Majoris (UM). M63 (RA 13 15 49.28 Dec +42 01 46.5) is one-third the distance between Beta CnV and Eta UM. M51 (RA 13 29 52.37 Dec +47 11 40.8) resides near visual star 24 CnV. You’ll find M101 (RA 14 03 12.51 Dec +54 20 53.1) to the other side of Alkaid. The accepted designation for M102 (RA 14 03 12.59 Dec +54 20 56.7) is lenticular galaxy NGC 5866, located southeast of Iota Draconis. You’ll find small globular cluster M53 (RA 13 12 55.30 Dec +18 10 09.0) northeast of Alpha Comae. M64 (RA 12 56 43.88 Dec +21 41 00.1) is about one-third the distance from Alpha Comae to Eta UM. M3 (RA 13 42 11.23 Dec +28 22 31.6) is one-third the distance between Arcturus and Cor Caroli.

Now for the incredibly rich galaxy fields near Coma Berenices and Virgo. Identify the easternmost star in Leo – Denebola – and head a fist-width due east. M98 (RA 12 13 48.29 Dec +14 54 01.2) is west of star 6 Comae. Return to 6 Comae and drop 1 degree southeast for M99 (RA 12 18 49.52 Dec +14 25 00.4).

Congratulations! In just 5 days you have logged 50 of the brightest and most beautiful members of the deep sky!

Wednesday, March 25, 2009 – Today celebrates the 1786 birth of Giovanni Amici, inventor of the achromatic lens, and in 1923, the birth of Kenneth Linn Franklin, radio astronomer. Tonight continue our marathon around midnight. It’s time to dance…

Leo’s easternmost bright star Denebola points to 6 Comae, about three finger-widths east. Two degrees northeast of 6 you’ll pass two 5th-magnitude stars leading to M100 (RA 12 22 54.95 Dec +15 49 19.5), the largest-appearing galaxy in the Coma-Virgo cluster. Continue 2 degrees north for bright yellow 11 Comae. One degree northeast is 9th magnitude, round M85 (RA 12 25 24.23 Dec +18 11 26.9). Try a “trick of the trade” to locate two more. Return to 6 Comae, relocate M99, turn off your drive, and take a break for 14 minutes. When you return, the elongated form and near-stellar nucleus of M88 (RA 12 31 59.34 Dec +14 25 13.4) will have ‘‘drifted’’ into view. Wait another 2–3 minutes, and the faint, barred spiral M91 (RA 12 35 26.58 Dec +14 29 45.1) will join the show in a 1-degree field of view.

Now locate bright Vindemiatrix (Epsilon Virginis), a handspan due east of Denebola. Hop 4.5 degrees west and a shade north to locate the largest elliptical galaxy presently known, M60 (RA 12 43 40.19 Dec +11 33 08.9). This magnitude 9 galaxy can be spotted with binoculars, but a telescope will reveal faint NGC4647, which only appears to be interacting with M60. In the field west is our next Messier: bright-cored elliptical M59 (RA 12 42 02.39 Dec +11 38 45.1). (Yes, there’s more, but not tonight. Let’s keep our studies to only the Messiers!) Move a degree west for fainter M58 (RA 12 37 43.48 Dec +11 49 04.4). About a degree north will locate face-on spiral M89 (RA 12 35 39.81 Dec +12 33 22.8). One half degree northeast is delightful 9.5 magnitude M90 (RA 12 36 50.08 Dec +13 09 45.7), whose dark dust lanes show in larger scopes. Continue 1.5 degrees southwest for M87 (RA 12 30 49.42 Dec +12 23 28.0), the first radio source galaxy discovered. M87 contains a black hole, and more than 4,000 globular clusters surround its elliptical form.

Now take a break… Things are about to get a lot hotter!

Thursday, March 26, 2009 – Starting at midnight now. Dawn is only a few hours away and the beginning of a new day. It is also a New Moon and the perfect time to try all 110 Messier objects in just one night! What’s that? You want to keep on going ten at a time? Then let’s do just that…

Slightly more than a degree northwest of M87 is the same-field pair, western M84 (RA 12 25 03.74 Dec +12 53 13.1) and eastern M86 (RA 12 26 12.20 Dec +12 56 44.5). Head to 31 Virginis and identify splendid variable R a degree west. Two degrees northwest is galaxy M49 (RA 12 29 46.76 Dec +07 59 59.9). Shift 3 degrees southwest for the handsome yellow double 17 Virginis. A half degree south is large face-on spiral M61. Now go for Spica, and 11 degrees due west. M104 (RA 12 39 59.43 Dec -11 37 23.0), the Sombrero Galaxy, will be your reward for a job well done. Congratulations! You’ve just seen 15 of the finest galaxies in the Coma–Virgo region in just hours, and our “Marathon” continues.

Five degrees south-southeast of Beta Corvi is your marker star, the double A8612, for the same field globular M68 (RA 12 39 28.01 Dec -26 44 34.9), and the Southern Pinwheel, M83 (RA 13 37 00.78 Dec -29 51 58.6) is 10 degrees southeast of Gamma Hydrae. Now make a wide move and head southeast of Arcturus for Alpha Serpentis. Eight degrees southwest is outstanding globular cluster M5 (RA 15 18 33.75 Dec +02 04 57.7) sharing the field with 5 Serpens. Now locate the ‘‘keystone’’ shape of Hercules, and identify Eta in its northwest corner. One-third the way between it and southern Zeta is the fantastic M13 (RA 16 41 41.44 Dec +36 27 36.9), the “Great Hercules Globular Cluster.” More difficult is M92 (RA 17 17 07.27 Dec +43 08 11.5), because there are no stars to guide you. Try this trick: using the two northernmost stars in the “keystone” asterism and form an equilateral triangle in your mind, with its apex to the north. Point your scope there. Way to go, astronomer! You have now passed the most difficult part of the “mini-thon,” and just think of the rewards! In less than a week, you have conquered over half of the Messier catalog.

While you spend a sleepy day, think about a French amateur astronomer who was watching a round black spot transit the Sun today in 1859. His name was Lescarbault, and he was sure he’d witnessed a new planet, which he christened “Vulcan.” Nathaniel Bowditch was also born this date in 1773. He also devised the “Bowditch Curve,” which applies in both physics and astronomy.

Be sure to join us next Friday as we conclude our Messier Marathon special! Until then? Dreams really do come true when you keep on reaching for the stars….

This week’s awesome images are (in order): M74 and M34 (credit – Palomar Observatory, courtesy of Caltech), Halton Arp (historical image), M38, M96, M106, M99, M87 and M61 (credit – Palomar Observatory, courtesy of Caltech). Thank you so much!!

March 19, 2009January 24, 2021 by Tammy Plotner

Vernal Equinox – Busting the Myth of Balancing Eggs

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Spring officially arrives for everyone, including astronomers on March 20. The word “Equinox” literally means “equal night”. It’s all about the balance of light – not the myth of balancing eggs. On the universal date (UTC) of Friday, March 20, 2009 at 11:44 (am) both the day and night are the same length. But what’s so special about it? It’s a date that most of us recognize as symbolic of changing seasons. North of Earth’s equator we welcome Spring, while people south of the equator are gearing up for the cooler temperatures of Autumn. But what’s all this about balancing eggs?

These all too brief, but monumental moments in Earth-time, owe their significance to the slightly more than 23 degree tilt of the Earth’s axis. Because of our planetary angle, we in the northern hemisphere receive the Sun’s rays most directly during the Summer. In the Winter, when we are tilted away from the Sun, the rays pass through the atmosphere at a greater slant, bringing lower temperatures. If the Earth rotated on an axis perpendicular to the plane of the Earth’s orbit around the Sun, there would be no variation in day lengths or temperatures throughout the year, and we would not have seasons. At Equinox, the midway between these two times in Spring and Autumn, the spin axis of the Earth points 90 degrees away from the Sun.

If your head is spinning from all of this, sit and ponder for a moment. Now is a great time to choose a marker and observe what’s happening for yourself. Trying a real science experiment for equinox is much better than the myth of balancing eggs. Just place a stake of some type into the ground (or use a fencepost or signpost) and periodically over the next few weeks measure the length of the shadow when the Sun is at its highest and write down your measurements. I use my south facing deck railing and mark its shadow on the deck boards in chalk. It won’t take long before your marker’s shadow length changes and you notice how the Sun’s position changes in the sky, and with it the ecliptic plane.

In the language of astronomy, an equinox is either of two points on the celestial sphere where the ecliptic and the celestial equator intersect. The Vernal Equinox is also known as “the first point of Aries” – a the point at which the Sun appears to cross the celestial equator from south to north. This is also the the zero point of longitude – the reference plane at which right ascension is defined as 0. Believe it or not, this was defined in 1950 as the northern vernal equinox, but it has moved to the constellation of Pisces now! Why? The equinoxes are not fixed points on the celestial sphere but move westward along the ecliptic, passing through all the constellations of the zodiac in 26,000 years. This is what’s known as the precession of the equinoxes – a motion first noted by Hipparchus roughly in 120 B.C. But what causes it?

The precession is caused the gravitational attraction of both the Moon and Sun on the equatorial bulge of the Earth. Imagine the Earth’s axis patterning itself in a cone as it moves, like a spinning top. As a result, the celestial equator, which lies in the plane of the Earth’s equator, moves on the celestial sphere, while the ecliptic, which lies in the plane of the Earth’s orbit around the Sun, is not affected by this motion. The equinoxes, which lie at the intersections of the celestial equator and the ecliptic, now move on the celestial sphere. Much the same, the celestial poles move in circles on the celestial sphere, so that there is a continual change in the star at or near one of these poles.

After a period of about 26,000 years the equinoxes and poles lie once again at nearly the same points on the celestial sphere. Because the gravitational effects of the Sun and Moon aren’t always the same, there is some wobble in the motion of the Earth’s axis called nutation. This wobble causes the celestial poles to move, not in perfect circles, but in a series of S-shaped curves with a period of 18.6 years that was first explained by Isaac Newton in 1687.

So where did the urban myth of balance eggs on vernal equinox come from? Probably because at one time Easter was celebrated at this time and eggs play a very big role in the whole Esotere, rebirth, and cultural symbolism of this holiday. It may very well have been the good folks in China who orginally began the myth by patiently practicing standing eggs on end during vernal equinox to symbolize the restoration of balance to the world after a season of darkness. If this symbol of fertility could be balanced on such a day of significance, then surely nature was in harmony!

Go ahead and balance eggs for fun… But believe in science.

P.S. The Bad Astronomer Phil Plait has a tutorial video on his website, teaching you how to stand an egg on end, any time of the year. Click here to watch it.

Many thanks to Vasilij Rumyantsev (Crimean Astrophysical Obsevatory) for the excellent solar analemma as it appeared in the July 9, 2002 APOD.

March 18, 2009December 24, 2015 by Tammy Plotner

Turning the Tides – NGC 3109 by Ken Crawford

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Somewhere off in the far reaches of Hydra about 4.3 million light years away is a local subgroup of galaxies and a small, barred spiral that just seems to be quietly minding its own business. Or is it? NGC 3109 might not look like much at first, but this little island universe is really turning the tides…

First discovered by John Herschel on March 24, 1835 while in South Africa, NGC 3109 was first classed as an irregular galaxy – the dominating member of a small group of dwarf galaxies believed to be Local Group Member candidates – a determination which isn’t easy to make. “The Local Group dwarf galaxies offer a unique window to the detailed properties of the most common type of galaxy in the Universe.” says Mario L. Mateo, “Our understanding of these galaxies has grown impressively in the past decade, but fundamental puzzles remain that will keep the Local Group at the forefront of galaxy evolution studies for some time.”

What makes NGC 3109 and its little band of followers so interesting? Well, chances are it may not be a member of our Local Group at all, but the nearest of the outsiders. “The small Antlia-Sextans clustering of galaxies is located at a distance of only 1.36 Mpc from the Sun and 1.72 Mpc from the adopted barycenter of the Local Group. The latter value is significantly greater than the radius of the zero-velocity surface of the Local Group that, for an assumed age of 14 Gyr, has R_0=1.18+/-0.15 Mpc.” says Sidney Van den Bergh, “This, together with the observation that the members of the Ant-Sex group have a mean redshift of 114+/-12 km s^-1 relative to the centroid of the Local Group, suggests that the Antlia-Sextans group is not bound to our Local Group and that it is expanding with the Hubble flow. If this conclusion is correct, then Antlia-Sextans may be the nearest external clustering of galaxies.”

So, if NGC 3109 can hold those kind of secrets… What other kinds of secrets can it keep to itself? Try a tiny tidally interacting elliptical galaxy discovered in 1999 by Alan Whiting, George Hau and Mike Irwin. It’s called the Antlia dwarf and it was found to be just beyond the zero-velocity surface of the Local Group. “These data increase the number of certain (or probable) Local Group members to 36. The spatial distribution of these galaxies supports Hubble’s claim that the Local Group “is isolated in the general field.” Currently available evidence suggests that star formation continued much longer in many dwarf spheroidals than it did in the main body of the Galactic halo.” says Sidney Van den Bergh, “It is suggested that “young” globular clusters, such as Ruprecht 106, might have formed in now defunct dwarf spheroidals. Assuming SagDIG, which is the most remote Local Group galaxy, to lie on, or just inside, the zero-velocity surface of the Local Group yields a dynamical age >~17.9+/-2.7 Gyr. However, this value is meaningful only if the outer regions of the local Group are in virial equilibrium.”

Take a look at the full-size image done by Ken Crawford and check out all the red and blue super giant stars and scattered HII regions where new stars are forming – along with all the background galaxies. According to the work of D.G. Barnes; “A substantial warp in the disk of NGC 3109 is detected in the H I emission image in the form of an extended low surface brightness feature. We report a positive detection in H I of the nearby Antlia dwarf galaxy and measure its total neutral gas mass to be 6.8+/-1.4×105 M solar. We show the warp in NGC 3109 to lie at exactly the same radial velocity as the gas in the Antlia dwarf galaxy and speculate that Antlia disturbed the disk of NGC 3109 during a mild encounter ~1 Gyr in the past. H I data for a further eight galaxies detected in the background are presented.”

In the meantime, NGC 3109 continues to be an on-going object of study. Its many compact HII regions could be an indicator of planetary nebulae formations that are totally unlike anything we’ve seen before. “The excitation patterns of the PNe in NGC 3109 are very different from the excitation patterns of PNe in other galaxies.” says Miriam Pena, “This would imply that the evolution of PNe depends upon the properties of their progenitor stellar populations, which vary from galaxy to galaxy. This should affect the PN luminosity function and its use as a distance indicator.” And NGC 3109’s unique structure has equally fascinated Sebastian Hidalgo; “Its edge-on orientation (which simplifies the study of a possible halo) and the possibility that it could, in fact, be a small spiral (the smallest in the Local Group) makes its deep analysis of major relevance to understand the properties of dwarf galaxies and the transition from dwarf irregulars to spirals.”

Many thanks to Ken Crawford for this inspiring image!

March 15, 2009December 24, 2015 by Tammy Plotner

Journey Inside M104

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Almost every amateur astronomer is familiar with the Sombrero Galaxy (also known as M104 or NGC 4594) – an unbarred spiral galaxy in the constellation Virgo. We’ve seen it in both small and large telescopes, picked up its ghostly signature in binoculars and dreamed over its structure in photographs. Now, for the first time ever, Jukka Metsavainio is giving us the opportunity to visualize what it might be like to approach this amazing galaxy from space and see it in dimension. Step inside and let’s learn.

Like all our our “stereo” image produced for UT by Jukka Metsavainio, two versions are presented here. The one above is parallel vision – where you relax your eyes and when you are a certain distance from the monitor screen the two images will merge into one to produce a 3D version. The second – which appears below – is crossed vision. This is for those who have better success crossing their eyes to form a third, central image where the dimensional effect occurs. Jukka’s visualizations of what M104 would look like if we were able to see it in dimension comes from studying the object, photographing it, knowing the field star distances and the different wavelengths of light. Are you ready to “cross” the boundary? Then let’s rock…

Discovered by Pierre Mechain in 1781 and added by Charles Messier’s own hand to his personal notes on May 11, 1781, Messier Object 104 wasn’t officially added to the official catalog of Messier objects until 1921 by Camille Flammarion. Although Messier had already ended his studies, he hadn’t quite ended his fascination with the sky and when Pierre discovered this amazing galaxy, he confirmed his observation by adding his description of a “very faint nebula” to the records. On May 9, 1784 – almost three years later to the date – Sir William Herschel independently recovered the galaxy and whose notes state: “Extended [elongated]. Very bright toward the middle. 5 or 6′ long.”

By 1828, John Herschel was seeing things much differently: “There is a faint diffused oval light all about it, and I am almost positive that there is a dark interval or stratum separating the nucleus and general mass of the nebula from the light above (s of) it. Surely no illusion.” Then Emil Dreyer in 1877: “Remarkable, very bright, very large, extremely extended toward position angle 92 deg, very suddenly much brighter toward the middle where there is a nucleus.” And the results of Curtis from the same year “A remarkable, slightly curved, clear-cut dark lane runs along the entire length to the south of the nucleus; probably the finest known example of this phenomenon. There are very slight traces of spiral whorls.” But it was 1912 and Vesto M. Slipher at Lowell Observatory who was about to make the most amazing discovery of all…

During 1910, Slipher (and later Carl Wirtz) was the first to use a spectroscope to observe the radial velocities of galaxies. What Vesto noticed was that M104 appeared to be cruising away from Earth at 700 miles per second. Such an tremendous speed was an important clue that the Sombrero was really another galaxy, and that the universe was expanding in all directions – but they didn’t know that at the time. At home (within our Milky Way galaxy) noted redshifts almost always correspond to the line of sight velocities associated with the objects being observed. These observations of redshifts and blueshifts have allowed science to measure velocities by a method first designed in 1868 by British astronomer William Huggins. Redshift is also an important tool to measure the velocity of gas of interstellar clouds, the rotation of galaxies, and the actions of accretion around neutron stars and black holes.

What we know now is there’s a supermassive black hole at the center of the Sombrero… one of the most massive black holes measured in any nearby galaxies. According the the findings by a research group led by John Kormendy and using spectroscopy data from both the CFHT and the Hubble Space Telescope, the group showed that the speed of rotation of the stars within the center of the galaxy could not be maintained unless a mass 1 billion times the mass of the Sun was present at the core. No wonder the eye is drawn there! The nucleus is also a strong source of synchrotron emission – produced when high velocity electrons oscillate as they pass through regions with strong magnetic fields. Although we can’t see radio waves, the low ionization nuclear emission region (LINER) at M104’s heart may be the energy source that weakly ionizes the gas in the Sombrero Galaxy.

And what of the dark dust ring? It’s cold atomic hydrogen gas. According to infrared spectroscopic studies, it’s the primary site for star formation and not the amazing nucleus. “The brightest infrared sources in the galaxy are the nucleus and the dust ring. The spectral energy distribution of the AGN demonstrates that, while the environment around the AGN is a prominent source of mid-infrared emission, it is a relatively weak source of far-infrared emission, as had been inferred for AGNs in previous research.” Says George Bendo, “The weak nuclear 160 um emission and the negligible polycyclic aromatic hydrocarbon emission from the nucleus also implies that the nucleus is a site of only weak star formation activity and the nucleus contains relatively little cool interstellar gas needed to fuel such activity. We propose that this galaxy may be representative of a subset of low-ionization nuclear emission region galaxies that are in a quiescent AGN phase because of the lack of gas needed to fuel circumnuclear star formation and Seyfert-like AGN activity.”

Take the time to check out this beautiful galaxy yourself. You’ll find it eleven degrees west of Spica….

March 13, 2009December 24, 2015 by Tammy Plotner

Weekend SkyWatcher’s Forecast – March 13-15, 2009

Greetings, fellow SkyWatchers! With the Moon gone from the early evening skies, it’s time for a little sky dancing this weekend. Are you ready for a little old stepping out and a little new? Then waltz this way as we check out some very new star clusters and interesting asterisms! Grab your binoculars and telescopes and I’ll meet you in the back yard….

Friday, March 13, 2009 – Today note the 1886 birth of Albert William Stevens, a daring balloonist who took the Explorer II to an altitude of 72,395 feet. He took the first photo showing Earth’s curvature and the first solar eclipse photo of the Moon’s shadow on Earth. Also, salute the 1855 birth on this date of Percival Lowell, who predicted the existence of Pluto (but Clyde Tombaugh was the one who actually discovered it, on Lowell’s 75th birthday!). Sir Percival was a determined soul who spent his life trying to find proof of life on Mars. He founded Lowell Observatory in 1894, where he studied Mars intensively, drawing the Red Planet covered with canals and oases. As Lowell once said: ‘‘Imagination is as vital to any advance in science as learning and precision are essential for starting points.’’

Tonight we’ll look at a bright collection of stars located less than a handspan west of Procyon. Its name is Collinder 106 (RA 06 37 19 Dec -05 57 55). At a combined magnitude of 4.5, this expansive open cluster can be spotted as a hazy patch with the unaided eye and comes to full resolution with binoculars. It contains only around 14 members, but this widely scattered galactic collection has helped scientists determine size scales and dispersion among groups of its type. Viewed telescopically at low power, the observer will find it rich in background stars and a true delight in a low power, wide field eyepiece. If you’d like a challenge, hop a half degree to the northeast to spot Collinder 111 (RA 06 38 42 Dec -06 54 00). While visually only about one-tenth the apparent size of its larger southwestern neighbor, spare little Collinder 111 also belongs to the same class of open clusters. Who knows what may lurk around these understudied clusters?

Saturday, March 14, 2009 – Before dawn, look for the close appearance of Spica and the Moon to celebrate today’s famous astro births, starting with astronaut Frank Borman (b. 1928), a crew member of Apollo 8, the first manned flight around the Moon. Next, astronaut Eugene Cernan (b. 1934), who floated in space for more than 2 hours during the Gemini 9 mission and piloted Apollo 10. How about Giovanni Schiaparelli (1835), the Italian astronomer who described Mars’s ‘‘canali’’ and named its ‘‘seas’’ and ‘‘continents.’’ Schiaparelli’s comet studies demonstrated that meteoroid swarms existed in the path of cometary orbits, and thus predicted annual meteor showers. He was first to suggest that Mercury and Venus rotate and discovered the asteroid Hesperia. Still not enough? Then wish a happy birthday to Albert Einstein (b.1879), the German–American physicist considered the most brilliant intellect in human history!

For a moment let’s reflect on Einstein’s Cross, proof of his genius. We can’t observe this Pegasus-based gravitational lens right now, but we can try to understand Einstein’s theory of gravity as an effect of the curvature in space–time. For example, if you draw a line around the center of a ball, the line would be straight, eventually coming back to its point of origin. We don’t see the point until we reach it, but we know it’s there. Einstein knew this dimension existed and predicted any object with mass will bend space and time around it, just like our line around the ball. He predicted light would also follow a curved path around an object… such as a distant quasar located behind a closer galaxy!

Tonight’s object is a ‘‘cross’’ astersim of stars. Begin at Procyon and shift about 10 degrees southwest (or 2 degrees south of 18 Monocerotis) to locate this pretty grouping of stars. Yes it’s true. It’s just an unknown, undocumented, and unnamed asterism, but how fitting to honor all these famous astro figures and a brilliant man who once said: ‘‘The fairest thing in life we can experience is the mysterious. It… stands at the cradle of true art and true science.’’

Now let’s go for a a challenging study. Larger telescopes should look for diminutive Bochum 2 less than half a degree northeast of ‘‘Einstein’s Asterism’’ (RA 06 48 50 Dec 00 22 35). At low power, it’s just a tight configuration of stars, but test the limit your telescope and increase magnification. This young open cluster has been studied for internal kinematics, spectroscopic binaries, and its motion in the galaxy, but its most interesting feature is a trapezium system at its heart. After a 4-year study, two of the members were documented as close binary stars with highly eccentric orbits, and one of the members is leaving as a runaway!

For smaller optics, continue another half degree east for NGC 2301 (RA 06 51 48 Dec -00 28 00). Even telescopes as small as Lacaille’s can see this bright, 2,500 light-year-distant open cluster. Studied for its variable stars, NGC 2301 is also on many binocular deep-sky observing lists!

Sunday, March 15, 2009 – Today marks the 1713 birth of Abbe Nicolas Louis de Lacaille, the French astronomer who named 15 of the 88 constellations. Using only a half-inch refractor, Lacaille made 26 new discoveries and charted 9,776 stars, creating the first southern star catalog. Sharing the date is William Rutter Dawes (b. 1799). ‘‘Eagle-eyed’’ Dawes made exhaustive measurements of binary stars, discovered Saturn’s inner Crepe Ring, and accurately mapped Mars. Dawes also devised the elegantly simple formula (Dawe’s Limit) of dividing the number 11 by the aperture in centimeters to give the arcseconds of resolution required to split a binary star.

Thankfully, somebody was watching the sky at 5:30 p.m. on this date in 1806, because the observed fall of a pristine 6-kilogram chondrite meteor made an indisputable case that chondrites carried carbon-based organic chemicals. Perhaps it was from one of the Corona Australid meteors whose shower peak is tonight after midnight? The fall rate is about 5–7 per hour, and best for our friends in the southern hemisphere!

Tonight let’s return to the Einstein’s Asterism and drop 15 degrees due southeast to study open cluster NGC 2360 (RA 07 17 42 Dec -15 38 00). At a distance of 4,600 light-years, magnificent NGC 2360 contains around 40 members, 7 of which are red giants. You have Caroline Herschel to thank for this lovely cluster… and her birthday is tomorrow!

Now, return to our Einstein’s Asterism and head slightly more than half a degree west to study scattered open cluster Dolidze 25 (RA 06 45 06 Dec -00 18 00). This low power, telescopic only, galactic cluster is a worthy study for those who seek the unusual. Located at the outer edges of our own galaxy, Dolidze 25 may very well be the product of the merger of the Milky Way and the Canis Major Dwarf galaxy. Extremely rich in oxygen and significantly deficient in metals, this huge starforming region contains young stars, pre-main sequence stars, and Delta Scuti types. With its thin veil of nebula, Do25 should prove to be challenging and quite to your liking! Hop another half degree west, and then slightly south for Dolidze 23 (RA 06 43 12 Dec -00 00 00). This telescope-only cluster reveals around a dozen easily resolvable stars at low power. Dolidze 23’s two brighter members are finderscope visible. Locate the cluster at low power, and place it at the south edge of the field of view. Turn off your drive units and allow the field to cruise by naturally as you observe. This allows Dolidze 25 to drift across your line of sight, a technique that often improves your ability to spot fine detail in fainter objects.

Celestial scenery alert on Tuesday, March 17! A few hours before dawn, the Moon and mighty Antares will be nearly touching, separated by only a fraction (0.2) of a degree. For some, this could be a wonderful occultation event, so be sure to check maps and resources! Although the occultation path is limited, even more so is the graze path, just a few kilometers wide. For these lucky viewers, brilliant red Antares may flash in and out of view several times as it moves slowly along behind the lunar mountains.

Until next week, dreams really do come true when you keep on reaching for the stars!

This week’s awesome photos are: Sir Percival Lowell (historical image), Collinder 106 (credit – Palomar Observatory, courtesy of Caltech), Einstein’s Cross (credit – HST/NASA), “Einstein’s Asterism’’ (Credit – Palomar Observatory, courtesy of Caltech), Bochum 2, NGC 2301, Dolidize 25 and NGC 2360 (credit – Palomar Observatory, courtesy of Caltech). Thank you so much!

March 9, 2009December 24, 2015 by Tammy Plotner

The Basketball Player In The Moon – Catch It Tonight!

The Basketball Player In The Moon - Ed Murray

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You’ve heard about the Man In the Moon and the Lady in the Moon… If you’re into lunar observing then you know about the Cow Jumping Over the Moon and the Rabbit in the Moon, too. But have you ever heard about the Basketball Player In The Moon? Well, step inside and find out more…

First discovered by Ed Murray and published in ALPO’s monthly “The Lunar Observer” and in NASA’s Dr Tony Phillips November 13, 2008 issue of Spaceweather.com, the “basketball player” is a compilation of lunar features that resemble… well… a basketball player! How did it’s discovery come about? Just ask Ed.

“Like many amateur astronomers, I guess I’ve always daydreamed just a little bit about possibly discovering a faint fuzzy that turns out to be a bright comet, but very quickly, I have to come down to Earth because living in suburban Philadelphia, with our weather and horrid light pollution, the chance of that happening are slim to none. So, I’ve had to be content with the memories of being able to see the solar eclipse from Hawaii, where I happened to see the Milky Way in all it’s glory from the 9,000 ft level visitors center, the annular eclipse of 1994 in New York… seeing the shadow bands … not on a white sheet but freshly cut green grass, numerous Aurorae and everything else…. until one night….”

Yes! Yes. That one grand night when one plus one makes two. And two suddenly makes sense! “Like many, I did have that National Geographic Map of The Moon but after numerous moves across the country and two college dorms, it, like many things, lay in tatters and eventually found it’s way to the great map room in the sky. So, you might understand how happy I was to find out that National Geographic had re-issued it and I could purchase another copy and so it remained opposite my bed for a few years… Until one night last year… When I looked at it and saw the basketball player, and promptly forgot it. Saw it a second time and forgot it. Saw it a third time, early on May 12. 2008 and realized that maybe this is something I should check out.”

And check it out he did. As a Dark Sky Advocate and once President of the Bucks-Mont. Astronomical Association, Ed double checked what he could see from his maps with what he could see against the sky and came to the same conclusion. It looks like a basketball player. Like all good observers, he turned in his findings to as many organizations and observing clubs as he could. Of course, Fritz Zwicky would have sure understood the response he got from the “professionals”, but the rest of the world will be happy to know that the Basketball Player has been added to the roles of the Unofficial Lunar Nomenclature site and acclaimed by SpaceWeather.

When can you see the Basketball Player In The Moon? When it rises tonight would be a great time to start. This is when the lunar east limb will appear to make the “player” be upright and easiest to spot. Later in the evening, as the Moon progresses across the sky, the view will appear to turn sideways. Still there… Just oriented a little differently! If you’re clouded out tonight, try again tomorrow – or whenever the Moon nears Full.

In the meantime? Why not wish Ed a big round of congratulations for an observing job – and discovery – well done!

March 6, 2009December 24, 2015 by Tammy Plotner

Weekend SkyWatcher’s Forecast – March 6-8, 2009

Greetings, fellow SkyWatchers! Ah, yes… the Moon is back in force and that will make for a rather quiet astronomy weekend – or will it? Why let a little reflected sunlight spoil the fun when we can take a look at just how important that studying sunlight really is, or just who drew the line at its studies?! How about taking a look for some very cool lunar craters and some very hot stars? More? Then waltz around the rings of Saturn and challenge yourself to a new star grouping. When ever you’re ready, I’ll see you in the back yard…

Friday, March 6, 2009 – If you see sunshine today, then celebrate the 1787 birth on this date of Joseph Fraunhofer—a trailblazer in modern astronomy. His field? Spectroscopy. Fraunhofer developed scientific instruments and specialized in the area of applied optics. While designing the achromatic objective lens for a telescope, he saw the spectrum of sunlight as it passed through a thin slit and the dark emission lines. Fraunhofer recognized that they could be used as wavelength standards, so he began measuring, labeling the most prominent with the letters still used today. His skill in optics, mathematics, and physics led Fraunhofer to design and build the very first diffraction grating.

You’ve probably seen these little rainbows hundreds of times in your life without even realizing what they are. Would you like to create your own grating? Take a piece of ordinary clear cellophane (a bit of clean food wrapping is fine) and scratch it lightly a few times in one direction only with a piece of sandpaper. Hold it adjacent to a bright light source and tilt it until you see hundreds of hair-fine lines of color. Yes, it’s crude. . . but it works! Did Fraunhofer’s telescope designs also succeed? Of course! His achromatic objective lens is still used in modern telescopes.

Tonight the lunar crater for named for Fraunhofer is visible, but so overlighted it will be difficult to see. Honor the man of lines by looking for another ‘‘line’’ on the Moon. If conditions are right, you’ll notice a thin black line cutting across the scenery not too far
from Arzachel. Crater Thebit and bright Thebit A will guide you. The line is the shadow of an impressive lunar fault called Rupes Recta, or the ‘‘Straight Wall.’’ During lunar sunrise, we can only see the shadow on the floor of Mare Nubium, but during third quarter, the escarpment is lit in brilliant white!

When you’re done, let’s take a look at Alpha Leonis, one of the closest bright stars to the ecliptic and known as far back as medieval times. Some cultures referred to it as the ‘‘fallen angel,’’ ‘‘the heart of the lion,’’ and the ‘‘yellow emperor.’’ We know it more commonly by its Latin name—Regulus. It’s not terribly massive, only about 3.5 times larger than our own Sun and just a few hundred million years old. But unlike Sol, 77.5-light-year-distant Regulus rotates to the extreme, revolving on its axis in less than 16 hours. Because of this rapid spin, its photosphere stretches, giving the star an oblate profile. As a victim of gravity darkening, Regulus’ poles are far hotter than its equator and 500% brighter. If it rotated any faster, centripetal force would pull it apart! But the ‘‘Little King’’ isn’t alone in space; it has two other members in its local court – a gravitationally bound 0.006-light-year-distant binary system. The brighter of the binary companions can be spotted in binoculars, but it will require a telescope to see the fainter third star another 15 billion kilometers away. The pair happily live out their lives orbiting each other about every 2 millennia, and around Regulus itself every 130,000 years.

Saturday, March 7, 2009 – Today we celebrate two notable births. The year 1837 is Henry Draper’s, first to photograph the stellar spectrum; and 1792 is the year Sir William Herschel’s only child—John—was born. John Herschel began his astronomical career in 1816 when he built his first telescope. His path led him to eventual British knighthood for furthering his father’s work, and to South Africa to complete his father’s survey by cataloging the stars, nebulae, and other objects of the southern skies. In his own words;

‘‘He that on such quest would go must know not fear or failing.’’

John returned to England in 1838, published his work, fathered 12 children, named the moons of Saturn and Uranus, and expanded the field of photography. He was a prodigious author, and you’ll even find examples of his handiwork in the Encyclopedia Britannica!

Tonight honor the great J. Herschel by identifying the lunar crater named for him in the lunar northern hemisphere. Once you have located J. Herschel, power up. Caught on this oblique crater’s edge is the deep pit of Horrebow—and a nice double strike. Compare the 156-kilometer diameter interior of J. Herschel to the smoothness of bordering Mare Frigoris. The difference in textures is astonishing! If the view holds steady, look for the larger C crater inside the walls, and a very distinct, drifted look to the crater rims. If John Herschel were alive tonight to share the eyepiece with you on his birthday, he would have said:

‘‘In circumstances where the uninformed and unenquiring eye perceives neither novelty nor beauty, the scientist and natural philosopher walks in the midst of wonder.’’

With such bright sky, it’s going to be difficult to practice much astronomy—or is it? There are always some very cool things to do if you just know where to look! Let’s head for the eighth brightest star in the sky—Procyon.

Often called ‘‘the one who proceeds the Dog,’’ Procyon also represents a dog, the beloved pet of Helen of Troy. If you haven’t noticed, Alpha Canis Minoris is also the eastern member of what is sometimes called the ‘‘Winter Triangle,’’ appearing above the horizon before the Dog Star, Alpha Canis Majoris. At 0 magnitude, it’s in fair competition with the other trio members: dazzling Sirius and mighty Betelgeuse. At a little more than 11 light-years away, it is also one of the closest stars to our Solar System.

Now just stop and look at this beautiful star. Arabic tales describe Procyon and Sirius as two sisters, who along with their brother—Canopus—tried to cross the sky when they came to the Great Sky River. When they both entered the Milky Way and tried to swim across, only Sirius was strong enough to make it and now stands on the southern bank of that river of stars. Left alone to the north as her siblings moved on, Procyon is often referred to in mythology as ‘‘she who weeps.’’ Not surprisingly, astrology also associates Procyon with watery catastrophes!

Sunday, March 8, 2009 – On this date in 1618, Johann Kepler formulated his Third Law of Planetary Motion. Too bad he couldn’t stick around until 1804 to meet Alvan Clark, the ‘‘father’’ of the refractor who was born on this day. Clark refracting telescopes and optics graced the great observatories of the world.

Tonight we’ll turn our own telescopes toward Saturn. For a small telescope at low power, a first glimpse of Saturn is far from the grand image often portrayed of the ringed planet. Instead of beautiful, Hubble-like images, the viewer is greeted with something that looks more like a sesame seed on a black saucer than a fascinating distant world. But don’t give up! No matter what telescope size you use, the image is more dependent on seeing conditions (such as the steadiness of the atmosphere and transparency) rather than aperture.

Even at low power, watching Saturn’s moons orbit over a period of days is very rewarding. And even a very small telescope will reveal Saturn’s ring structure. As optic size increases, so do details on successive nights. Look for such wonders as the wide dark band known as the Cassini division and the dark shadow of the planet’s orb against the rings. Sharp-eyed observers often spy the ‘‘Encke gap’’—the thin, minor ring around the outside. Subtle shadings and the ring shadows on Saturn’s yellowish globe await! Try sketching while observing, even if you throw it away later. When sketching, the eye and the mind coordinate to pick up on finer details than seen by just observing alone. Be sure to take plenty of time! When the one pure moment of seeing and stability combine, even the smallest of telescopes will reward you with a view you’ll never forget.

When you’re done, return to last night’s study star, Procyon, for another treat – a very pleasing little group of stars about a fist-width southeast (RA 08 25 39 Dec 02 54 23). The primary star’s name is C Hydrae, and although the group isn’t truly gravitationally bound, they’re a real delight to binoculars and telescopes of all sizes with their mixed magnitude similar spectral types!

Until next week? Ask for the Moon, but keep on reaching for the stars!

This week’s awesome images are: Joseph Fraunhofer (historical image), Area of Rupes Recta (credit—Roger Warner), Regulus – (Credit: Peter Wienerroither, PWs fotografisches Doppelstern Projekt / PWs Photographic Doublestar Project), John Herschel (historical image), Crater J. Herschel (Credit—Wes Higgins), Procyon (credit – UC Berkeley Department of Astronomy), Saturn (credit—Wes Higgins) and C Hydrae (credit—Palomar Observatory, courtesy of Caltech). Thank you so much!

March 1, 2009December 24, 2015 by Tammy Plotner

Comet Lulin Approaches M44 and Eskimo Nebula

Comet Lulin and Saturn in Parallel Vision by Jukka Metsavainio

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Have you ever wondered what it would be like to step into space and have a look at solar system objects in aspect? While we can view interesting and inspiring events like Comet Lulin’s recent conjunction with Saturn, what we can’t quite get our brains to wrap around it how it would appear in dimension. Thanks to some “magic” by Jukka Metsavainio and some of his own outstanding astrophotography – now we can…

Like all our our “stereo” image produced for UT by Jukka Metsavainio, two versions are presented here. The one above is parallel vision – where you relax your eyes and when you are a certain distance from the monitor screen the two images will merge into one to produce a 3D version. The second – which appears below – is crossed vision. This is for those who have better success crossing their eyes to form a third, central image where the dimensional effect occurs. In this case, Jukka had the opportunity to photograph Comet Lulin during its recent conjuntion with Saturn and he was willing to share the view in a visualization of how the pair would have appeared in binoviewers – or if you were able to see them with both eyes from space! Ready to get crossed? Then let’s go….

Comet Lulin and Saturn in Cross Vision by Jukka Metsavainio

After having just viewed Comet Lulin a few hours before seeing this image, I knew I just had to share. Thanks to the comet’s unique position along our ecliptic plane, the pleasure of catching it in the eyepiece with other telescopic objects isn’t over yet. For observers in the United States, on March 6, this Thursday evening, Comet Lulin will pass 2 degrees south of the Beehive Star Cluster, M44. On Saturday, March 14, Lulin will pass only 15 arc minutes (half the moon’s apparent diameter) away from the Eskimo Nebula, NGC 2392. But don’t think you have to live in the US to see it!

As with all conjunction events, your position and timing on Earth will play an important role on where the comet will appear in relation to the object. For example, for observers in the UK, Lulin may be to M44’s southeast – while the west coast of Canada will see it to the southwest. The same is true of latitude as well – your variation here on Earth will give an equal variation on Comet Lulin’s positon against the celestial sphere. But, don’t go crazy trying to worry about its exact position. Two degrees is a lot of sky and chances are no matter when you view on March 6, you’ll catch it in (or near) the same binocular field as the Beehive.

In the meantime? Enjoy this incredible look at Comet Lulin and Saturn… It’s a tasty treat!

February 27, 2009December 24, 2015 by Tammy Plotner

Weekend SkyWatcher’s Forecast: February 27 – March 1, 2009

Greetings, fellow SkyWatchers! Are you ready for the weekend? Then let’s tackle both fun and serious studies as we take on a bright open star cluster, Herschel 400 objects, lunar subjects, planets, comets and even a galaxy cluster. If you’re ready to learn more about the history behind the observing and have some fun under the stars, then just follow me…

Friday, February 27, 2009 – Today let’s celebrate the 1897 birth on this date of Bernard Lyot, master of optics. He invented the polariscope, and produced the first solar coronagraph. He also made the first motion pictures of solar prominences. Lyot was an astute observer, and realized that the lunar surface had similar properties to volcanic dust. He didn’t see canals on Mars but observed sandstorms there, as well as atmospheric conditions on other planets. The Lyot filter is well known, and so is his micrometer, a device used to make precise distance measurements, especially those between close double stars. By all accounts a wonderful and generous man, Lyot sadly died of a heart attack while returning from seeing an eclipse.

Honor Lyot’s work by studying two open clusters, found about a fist-width north of Xi Puppis. The brighter of the two – M47 (RA 07 36 36 Dec -14 29 00) – is 1,600 light-years away and a glorious object for binoculars. Filled with mixed-magnitude stars that resolve fully to aperture, M47 features the matched-magnitude double star Struve 1211 near its center. For all its bright beauty, this stellar swarm has the most ironic of histories. Probably discovered first by Hodierna but kept secret, it was independently recovered by Charles Messier, but its position was logged incorrectly. Later, it was cataloged by both William and Caroline Herschel. . .and yet again by John Herschel, who said: ‘‘This cluster has not since been observed. It is probably very loose and poor one.’’ Even Dreyer had a hard time nailing it down! Funny, considering it has only been there for 78 million years…

While M47 is a Herschel object, look just slightly north (about a field of view) to pick up another cluster that borders it, NGC 2423 (RA 07 40 45 Dec -9 09 00). This compressed cluster contains more than two dozen faint stars with a lovely golden binary at its center. By comparing the two clusters telescopically, you are also expanding your own studies by viewing two different types of stellar evolution: M47 is very similar to the Pleiades, while NGC 2423 more closely resembles the Hyades.

Saturday, February 28, 2009 – If you didn’t notice the beautiful visage of the tender young Moon and Venus last night at sunset, try again tonight. The pair will be even closer! For most observers, Venus will be only slightly more than a degree away from the Moon’s limb. Have you checked Venus’s phase in the telescope lately? Just like our own Moon, the inner planets (Mercury and Venus) have phases. Because they’re inside Earth’s orbital path, we only see a thin crescent when they first emerge from the Sun’s glare, and they become gibbous as they are about to pass behind the Sun from our point of view. That’s also the reason why we only see these two planets either after sunset or before sunrise!

Take a closer look at the slender crescent Moon. It, too, has only just emerged from the Sun’s glare, and now is the time to get a great look at two craters – Langrenus and Vendelinus. If you remember Mare Fecunditatis, you won’t have any trouble spotting Langrenus on its south shore about mid-way along the Moon’s visible limb. It’s a very old crater with an approximate diameter of 132 kilometers, and appears to binoculars as a shallow, bright ring; featuring a central peak. Further south is equally old Vendelinus. Slightly larger and spanning 147 kilometers, it will appear even more shallow – because it is. It lacks a central peak, but telescopes at high power can resolve its few minor interior craters.

Keep your binoculars or telescopes out for a while after the Moon sets, and let’s head a little less than a fist-width east-southeast of Alpha Monocerotis (RA 08 00 01 Dec -10 46 12) to check out NGC 2506. On a dark night, this nearly 7th magnitude object is one of the most impressive of the Monoceros open star clusters. Caught in a chain of stars, it displays a rich concentration, almost appearing like a globular cluster. NGC 2506 has been used to study old, metal-poor galactic clusters. Evolution has enriched its iron content, and – despite its extreme age – it is still a beauty. Be sure to mark your Hershel ‘‘400’’ notes!

Sunday, March 1, 2009 – In 1966, Venera 3 became the first craft to touch another planet when it impacted Venus on this date. Although communications failed before it could transmit data, it was still a milestone achievement. If you’re out at sunset, be sure to have a look at Venus and say “Spaseba!”

Once you’ve viewed Venus, let’s turn our observations toward tonight’s Moon and begin by identifying some prominent lunar craters around Mare Crisium that can be spotted easily with a small telescope. North you’ll spy Cleomides and at the western edge, Proclus. Near the terminator northwest is Macrobius, and southwest is Taruntius. Power up and identify the small wells of Peirce, Picard, and Lick inside the smooth sands of Crisium. Lather, rinse and repeat… The more often you repeat crater names to yourself (and aloud) the greater the chances are that you’ll retain these names in your memory. Now, let the Moon wester and we’ll go again…

In 2003, another Deep-Sky Companion book by notable observer and author Stephen O’Meara premiered. Known for his high-quality sketches of Solar System objects and uncanny observing skills, O’Meara was the first to sight Comet Halley in 1985, and sketch the dark spokes in Saturn’s rings (before Voyager had imaged them). Still part of the editorial staff at Sky & Telescope, and a treasured lecturer, let’s take just a moment to congratulate Steve on a lifetime of achievement! (folks? you will never meet a more genuinely kind person and one who treats fellow amateur astronomers with such huge respect. i have met a great many of my astronomy “heroes” over the years and steve-o is most definitely the kind of star i’d like to be some day.)

Are you ready to practice Steve’s powers of observation? Then begin with Comet Lulin – now speeding in the eastern edge of the dim constellation of Cancer. If you have difficulty finding it, look for the large, backwards question mark of the prominent asterism of Leo. The bright star you see that’s the “period” of the question mark is Regulus – and Comet Lulin is a couple of binocular fields west. Once you’ve spied it, try comparing details to what you may have observed of Lulin’s previous behavior and appearance. Is the comet moving faster than when you first began observing it? It the tail longer? Brighter? What direction does it point in? Has the coma become more diffuse or larger? Does the comet display a nucleus? Is the anti-tail still visible? Asking yourself simple questions like these will help you become a far better observer!

Now wait until Saturn has cleared the horizon murk and let’s take a close look at this fascinating planet. Look for details such as ring shadows on the planet and planet shadows on the rings. Can you see the Casinni Division? How about Saturn’s satellites? Tonight you’ll find Titan leading the way well outside to the west. To the western ring edge, you’ll see Tethys… And clustered together on the eastern ring edge are Rhea, Dione and Enceladus. You won’t need the Hubble Space Telescope to see these kinds of details – just a steady sky and around a 4″ telescope. Take your time and enjoy your studies!

Ready for some serious studies? Then let’s talk about George Abell, who was born this day in 1927. Abell was responsible for cataloging 2,712 clusters of galaxies from the Palomar sky survey, a task he completed in 1958. Using these plates, Abell proposed that the grouping of such clusters delineated the arrangement of matter in the universe. He developed the luminosity function, which shows the relationship between brightness and the number of members in each cluster, allowing you to infer the cluster’s distance. Abell also discovered planetary nebulae, and developed the theory (along with Peter Goldreich) of their evolution.

For seasoned observers, wait until the Moon has set and honor Abell by viewing one of his galaxy clusters – Abell 1367, located about a degree southwest of 93 Leonis (RA 11 44 44 Dec +19 41 59). It’s an area of challenging intrigue for a large scope – spanning a degree of sky and containing as many as two dozen small galaxies – a gemstone for the galaxy collector!

Until next week? Ask for the Moon… But keep on reaching for the stars!

This week’s awesome images are: Bernard Lyot (public image), M47 and NGC 2423 (Credit: Palomar Observatory, courtesy of Caltech), Langrenus and Vendelinus (Credit: Dave Nash), NGC 2506 (credit – Palomar Observatory, courtesy of Caltech), Crisium area (Credit: Greg Konkel), Stephen James O’Meara (Credit: Sky & Telescope), Saturn & Moons (Credit: NASA), George Abell (Credit: American Institute of Physics), Abell 1367 (Credit: Palomar Observatory, courtesy of Caltech). We thank you so much for sharing the history and mystery with us!