Category: Skywatching

Greetings, fellow SkyWatchers! What better way to celebrate a snow-bound weekend than by having a look at the “Eskimo”! While we’re at it, we’ll take a look at an awesome open cluster suitable for all optics and take an adventure towards one of the best supernovae remnants in the night sky. Along the way, we’ll explore some of the history and mystery behind these objects, so dust off your optics and I’ll see you in the backyard….

Friday, February 12, 2010 – Today is unofficially Physicist’s Day! We’ll begin by celebrating three notable births on this date, starting in 1893 with Marcel Minnaert, solar physicist. Minnaert’s innovative techniques in solar spectrophotometry aided the discovery of structure in the Sun’s outer layers. Next is 1918 and Julian Schwinger, a physicist big on electromagnetic field theory, who shared the Nobel Prize for work in quantum electrodynamics. Last is the 1936 birth of Fang Lizhi, who published his work on the Big Bang theory in 1972. Even in exile from Communist China, he continues to express his belief in freedom of intellectual expression and continues his work in theoretical cosmology.

Tonight we’ll time-travel back 5,000 years as we head for NGC 2392. Located about two fingerwidths southeast of Delta Geminorum (RA 07 29 10 Dec +20 54 42), this beauty is a planetary nebula commonly known as the ‘‘Eskimo.’’ Discovered in 1787 by Sir William Herschel, a small telescope will see it as a fuzzy green star, while aperture will reveal definite annulus around its central stellar point. A steady night helps to reveal details, and a nebula filter lights it up! NGC 2392 is so complex that it is not yet fully understood. As with Minnaert’s solar work, we know the glowing gases are the outer layers of its central star, shed 10,000 years ago, while the inner ribbons of light (called filaments) are areas where particles are being pushed away by the strong stellar wind. Even now, we still can’t quite explain the unusual outer filaments! It won’t look like a Hubble image in your telescope, but you can still marvel at a unique mystery—seeing its light as it was when ‘‘physicists’’ began using the first ‘‘computer’’—the newly invented abacus!

February 13, 2010 – We salute Johan Ludvig Emil Dreyer, who was born on this date in 1852. At age 30, Danish astronomer Dreyer became director of the Armagh Observatory—not a grand honor, considering the observatory was so broke it couldn’t afford to replace its equipment. Like all good directors, Dreyer somehow managed to get a new 1000 refractor but no funds for an assistant to practice traditional astronomy. However, J.L.E. was dedicated and within 6 years had compiled all observations known to him into one unified work called the New General Catalogue of Nebulae and Clusters of Stars (NGC). Originally containing 7,840 objects, and supplemented in 1895 and 1908 with another 5,386 designations, the NGC remains the standard reference catalog. Although Dreyer’s personal observations included such nebulous descriptions as ‘‘a vault of stars,’’ modern astronomers continue to use his abbreviations as a kind of shorthand.

Honor Dreyer tonight by discovering one of his catalog objects suited for all optics—NGC2287. Located about two finger-widths south of Alpha Canis Majoris (RA 06 46 00 Dec +20 46 00), only an open cluster this bright could stand up against brilliant Sirius. From a dark-sky location, your unaided eye can even spot this magnitude 4.5 star vault as a hazy patch. Aristotle saw it as early as 325 BC! Officially discovered by Hodierna, we know it best by the designation Messier Object 41. Even from 2,300 light-years away, the cluster’s brightest star, an orange giant, stands out clearly from the stellar nest. With large aperture, you’ll notice other K-type stars, all very similar to Sol. Although small scopes and binoculars won’t reveal too much color, you might pick up on the blue signature of young, hot stars. NGC 2287 could be anywhere from 190 to 240 million years old, but its stars shine as brightly now as they did in Aristotle’s day. . .and Dreyer’s!

February 14, 2010 – On this date in 1747, astronomer James Bradley presented his evidence of Earth’s wobble, called nutation. The study took 19 years, but won Bradley the Copley Medal! In 1827, George Clark was born. The name might not ring a bell, but it was indeed a bell—melted down—that he used to create his first brass telescope. George’s family went on to produce the finest—and largest—telescopes of their time. In 1898 one of my personal heroes, Fritz Zwicky came along, his name synonymous with the theory of supernovae. The Swiss-born Caltech professor was also a salty character, often intimidating his colleague Walter Baade and referring to others as ‘‘spherical bastards.’’ Although Zwicky was reportedly difficult to work with (geez… wonder why?), he was also brilliant—predicting the phenomenon of gravitational lensing. An unsung genius!

Tonight we’ll look at a supernova remnant as we venture to the Crab Nebula. Finding M1 is easy: it can be seen with as little as 7x magnification. Locate Zeta Tauri (about halfway between Orion’s ‘‘head’’ and the southernmost bright star in Auriga) and aim about 1 degree northwest (RA 05 34 31 Dec +22 00 52). Viewing M1 with small optics helps to understand why Charles Messier decided to compile his famous catalog. Unaware of its earlier discovery, Messier located a fuzzy object near the ecliptic and assumed it was the return of Halley’s Comet. Considering his primitive telescope, we can’t fault his observation. But Chuck was a good astronomer. When he realized the object wasn’t in motion, he began compiling a log of things not to be confused with comets—the famous Messier objects. Enjoy looking at this spectacular deep-sky jewel, and we’ll study it in depth another time. Of course, Zwicky may have cursed me for saying that observing without science is an ‘‘empty brain exercise and therefore a waste of time.’’ But on the date of his birth, I took his advice. . . ‘‘Give me a topic and I’ll give you an idea!’’

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

This week’s awesome stellar images are from Palomar Observatory, courtesy of Caltech. We thank you so much!

Greetings, fellow SkyWatchers! I don’t know about everyone else, but most observations here have been of the big M0. Clouds, clouds and more clouds! Perhaps we’re really in a nebula? However, for those fortunate few that do have clear skies, let’s take a look at what’s happening on the lunar surface each night. And, since we’ve got to deal with a little “Moonlight Sonata”, we’ll also inspect some bright stars and alternative catalog studies to add to your knowledge and pleasure of the night sky! Whenever you are ready, dust off your optics and I’ll meet see you in the backyard….

January 22, 2010: Start the astronomical day by observing the 1592 birth on this date of Pierre Gassendi, French scientist, mathematician, philosopher… and the first to use a Galilean telescope to observe a Mercury transit by the projection method. Gassendi was a prodigious observer, known for his humor, and was friends with Cassini, Galileo, Hevelius, and Kepler. His writings included work on falling bodies – a rare coincidence, since the only known piece of ‘‘space junk’’ to ever re-enter our atmosphere and strike a human occurred on the 405th anniversary of his birth!

Let’s begin our weekend by taking a look with binoculars at the first quarter Moon and see what we can discover… First repeat our first litany: #1—Mare Crisium, #2—Mare Fecunditatis, and #3—Mare Nectaris. Head north to the huge area of #4, Mare Tranquillitatis, which appears with its irregular borders. Beneath the smooth appearing regolith, the ‘‘Tranquil Sea’’ basin is cracked and overlapped by accompanying basins – lava spilling and flowing into other areas as large as the Kimberley region of Australia, or three times larger than England! Now, #5 Mare Serenitatis, the ‘‘Sea of Serenity.’’ Home to a violent past, its outer edges appear darker than the interior—mute testimony to continued seismic and volcanic activity allowing the basin to fill with lava more than once. Take a telescopic look at the rilles adorning this lunar desert, whose surface is the size of Italy. Then go north for #6, Mare Frigoris, the ‘‘Sea of Cold.’’ Congratulations on another learning exercise and if you’re thinking about how cold you are, think about how cold you’d be if you were observing Earth from Mare Frigoris!

Now open your eyes and let’s head for the star on Orion’s western shoulder, Gamma. Named Bellatrix, the 243 light-year distant ‘‘Amazon’’ is not actually part of the Orion association. Gamma is a foreground star and is the hottest of its type visually observable. Historically this star was used as a luminosity standard to compare with other stars to check for variability. But it was later discovered that Bellatrix itself is an eruptive variable, changing in luminosity by a few percent over time. It ranges in magnitude from 1.59 to 1.64. Sure, it’s a minor change – but still a change! There are a couple of types of eruptive variable stars, some with a broad range of increase in luminosity and a fixed time line. These types of eruptive variables include flare stars – very faint stars on the main sequence; novae and dwarf novae – which are caused by the sharing of material between evolved stars in binary systems; and supernovae – the violent and uber brilliant end for several classes of star.

Use binoculars to spot a fainter star about a half degree northeast and say hello to alternative catalog study Dolidze 21 (RA 05 26 50 Dec +06 58 30). This loose association of stars contains a few solar types, and many stars fainter than small optics can resolve – an unusual observation for your notes. Here we have what is considered a “poor” open cluster. Not because it isn’t nice – but because it isn’t populous. It is home to around 20 or so low wattage stars of mixed magnitude with no real asterism to make it special.

January 23, 2010: On the Moon the clockwork movement of the terminator has slowly marched across the surface, revealing more lunar landscape and its 12 maria for exploration. While it ticks along the ecliptic, Luna is passing by other orbiting bodies. Want a challenge? Then we’ll pass on the Moon and aim binoculars towards the constellation of Leo and take on an asteroid! Although Vesta isn’t as exciting, now is a good time to practice observing these rocky Solar System bodies. Spinning completely on its axis about every 5.5 hours and spanning 525 kilometers, this Arizona-sized minor planet is a treat for amateurs because its surface is highly reflective. At times Vesta can reach near unaided-eye visibility, but moonlight steals away fainter objects from easy view. Chances are very good that even in a starry field Vesta will be one of the brightest points visible. See if you can discover Vesta tonight!

Looking for an unusual star to spark your imagination? Then set your sights on the westernmost star of Orion’s ‘‘belt’’ – Mintaka. Like clockwork, astronomical objects can also keep incredibly accurate time. Located around 1,500 light-years away, Delta Orionis is a multiple star system: its companion star is almost equal in brightness and orbiting at a clockwork rate of 5.7325 days from only 8 million kilometers away. In astronomical terms, these two white-hot suns are nearly touching! Mintaka is a prime example of a spectroscopic binary star – a pair so close they are only detectable by changes in the stars’ spectra. Its stationary spectral lines proved the existence of interstellar matter! Take a closer look, and Delta Orionis will reveal a visible 6.7 magnitude companion to its north – a challenge well suited to small optics.

January 24, 2010: Tonight, let’s take time to work toward learning more major lunar features by sailing across 12 seas. The key to learning is to repeat these again and again: #1: Mare Crisium, #2: Mare Fecunditatis, #3: Mare Nectaris, #4: Mare Tranquillitatis, #5: Mare Serenitatis, and #6: Mare Frigoris. Excellent work! Now let’s go have a closer look at #7: Mare Imbrium. Identical in size to Saudi Arabia and about one-fourth the size of the United States, the ‘‘Sea of Rains’’ basin was formed 38 million years ago during a dramatic impact causing a Moon-wide series of faults. The massive strike shattered the lithosphere to a depth of 100 kilometers, embedding the impactor as a mascon. Seismic waves traveled through the interior—re-shaping the far side and creating magnetic anomalies—while the basin floor rebounded and flung ejecta 800 kilometers away. Over 500 million years, at least three areas of distinct lava flow poured into the impact basin (the oldest and largest about 1,200 kilometers long), far out-producing any earthly volcano. The youngest and smallest is about 400 kilometers in length, matching our terrestrial Columbia River Flood Basalt, an area stretching from Idaho to the Pacific Ocean! Now, here are some more to learn: #8: Mare Vaporum, #9: Mare Insularum, #10: Mare Cognitum, #11: Mare Nubium, and #12: Mare Humorum. Remember: repeat, repeat, repeat!

Now turn your eyes towards Orion and its Alpha star – Betelgeuse. Early in the evening, Orion the ‘‘Hunter’’ is beginning its journey across the night sky. Alpha stands out as an orangish star in the northeastern corner. It is a giant among stars! Betelgeuse has a long literary history and was one of the most massive stars known. In the mid-1800s, John Herschel observed that Betelgeuse varied in brightness, its light intensity changing by as much as a magnitude in under 6 years. The red giant is continually contracting and expanding to a formidable size – one that would fill the orbit of Jupiter around our own small star. But, it’s not alone…. Alpha also has four companion suns! Estimated to be 6 million years old, the light you see tonight from Betelgeuse left the
star around the time Nostradamus was making his predictions. Should it go supernova tomorrow, it would be almost another half century before this spectacular sight would be seen in our night sky!

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

This week’s awesome images are an historical photo of Gassendi, lunar images we done by Greg Konkel. Stellar and cluster images are from Palomar Observatory, courtesy of Caltech and the Betelgeuse diagram is courtesy of NASA. We thank you so much!

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Are you ready for some excitement that won’t take an observatory telescope to spot? Then get out your binoculars, because according to CBET 2128 there’s a new object showing its stuff off in the constellation Ophiuchus…

Released by A. Henden in AAVSO Special Notice #187: “CBET 2128 indicates that Hideo Nishimura has discovered a new outbursting object in Ophiuchus. This object has magnitude 8.4 on Jan 15.857UT, and is located at RA 17:39:40.94 DEC -21:39:47.9 J2000. No spectra have been reported, but K. Kadota has inspected the 1997 DSS red plate and finds no object at this position, with a limiting magnitude of 20. This object has now been added to VSX. You may submit observations as N Oph 2010, VSX J173940.9-213947, or with AUID 000-BJS-899. Note that there is a 10.3 magnitude irregular variable a few arcmin west of this position, so do not use it as a comparison star.”

Information on submitting observations to the AAVSO may be found at: http://www.aavso.org/observing/submit/. However, even if you don’t choose to submit an observation, it’s rather rare that an object of this type can easily be observed with even the most modest of equipment. Magnitude 8.4 is easily within reach of small binoculars, and given that most of the world isn’t having the best of luck with weather, you may be one of only a few who get to see it! Use this map to get you in the general area….

Once you have your position in the sky, use this more localized map to help you identify the nova. This field spans approximately 12 degrees – or about the same size as an average binocular field. I’ve filtered the stars to match the magnitude, so look for any star that’s as bright as – or brighter – than what you see within or very near to the red square area. You’ve discovered the nova! (Hint: Look for obvious star patterns that are easy to see, like the group of stars that seems to resemble Orion’s belt and sword just below the target area.) It might take you several tries and several minutes to locate it, but what a reward when you do!

Enjoy your observations….

Greetings, fellow SkyWatchers! It’s a dark weekend and time to get out and rock the night… If you’re up to the challenge, one of the finest and most exciting objects we’ll study here isn’t a Messier… it’s a comet. And not just any comet – but one that fits right into this time frame in history! Not up to hunting a moving object? Then we’ll take a look at two objects that could resemble comets and not only present a challenge, but add to the fun! Whenever you’re ready, dust your optics off and I’ll see you in the backyard….

January 15, 2010 – In 2006, Stardust was nearing Earth with its payload of cometary dust particles from Comet Wild 2. The tiny interstellar dust particles were collected by the spacecraft Stardust, which on January 15, 2006, completed its 7-year Odyssey in space by returning its samples to Earth. Two years before, on January 2, 2004, Stardust flew through the hail of rocks and dust that make up comet Wild 2’s coma, collecting invaluable samples of cometary particles that will help scientists decipher the history of our solar system. But during its long voyage Stardust also picked up a different type of sample — minuscule particles of interstellar dust that arrived at our solar system from distant stars, light years away. Stardust collected these particles between February and May 2000, and again between August and December 2002, while passing through a stream of dust that flows into our solar system from interstellar space. The stream was discovered quite recently — in 1993 by the spacecraft Galileo, which passed through that region of space on its way to Jupiter. When Stardust flew through the stream, it extended its tennis-racket shaped aerogel collector, picking up and storing the interstellar particles. No such pristine particles from distant stars have ever been collected before! Then, on January 15, 2006, Stardust swung by the Earth once more and released a sample return capsule, which parachuted safely down onto the Utah desert. Nestled within the capsule’s science canister were two sets of samples: cometary particles on one side of the aerogel collector, and interstellar dust on the other. Within days of arrival, mission scientists began extracting the dust grains from Wild 2 and preparing them for shipment to scientists around the world. Don’t forget to participate in StarDust@Home!

If you’d like to collect a little “stardust” of your own, then this weekend is a great opportunity to actually view Comet 81P Wild 2! Holding a near respectable magnitude 10 and cruising through Virgo (rough RA 13 10.7 and DEC -04 48). 81P Wild 2 has a distant and circular orbit which has it about 1.642 AU away from our Sun at the moment and it will continue to brighten slowly over the next couple of months and is expected to be its brightest (magnitude 9) towards the end of March and in early April. While Comet 81P Wild 2 is just a bit too faint to be found with average binoculars, even a small telescope will reveal its diffuse form. It won’t be bright, and it will appear more like a small, round nebulous patch rather than what folks traditionally think of as a comet… But history is out there waiting on you to come and collect on history!

January 16, 2010 – In 1978 on this date, NASA named 35 candidates for space shuttle missions, including Sally Ride as the first female U.S. astronaut and Guion Bluford, Jr., as the first black. In 1973, the Lunokhod 2 mission was beginning its robotic lunar expedition, and in 1969 Soyuz 4 and 5 became the first vehicles to dock in space and exchange cosmonauts. The year 1730 saw the birth of Jean Bochart – publisher of LaPlace’s planet/ecliptic theory. Although eventually beheaded for his politics, Bochart put together Europe’s largest collection of astronomical instruments and was renowned for his calculations of cometary orbits, made jointly with long-time friend and co-observer Charles Messier.

Tonight, venture into Lepus for a faint, round, fuzzy object that might easily be mistaken for a comet in a small telescope or binoculars – Messier Object 79 (RA 05 24 10 Dec +24 31 27). The true beauty of this object is revealed in large telescopes. Behold a globular cluster, one of many densely packed balls of stars that mainly congregate near our galactic center. Discovered by Pierre Mechain and cataloged by Messier in 1780, M79 is on the opposite side of our galaxy, and about 4,200 light-years away. Spanning 118 light-years, this starry sphere may not be an original member of our galaxy at all but an import. Although we can’t see it happening, the Canis Major Dwarf galaxy is slowly being incorporated into our own system, and M79 might very well be a product of this union!

Thanks to Mechain and Messier’s careful notes, William Herschel later recovered M79 and resolved its stars. Although the practice of maintaining an astronomy diary isn’t for everyone, keeping simple records is very rewarding. Make note of the object’s appearance, equipment used, and sky conditions. Observing diaries just like those of Messier and Mechain have led countless astronomers along the road of discovery to all the deep-sky objects we know today!

January 17, 2010 – Celebrate the 1723 birthday of Johann Tobias Mayer, the German astronomer who created the first lunar tables for determining longitudes at sea. His calculations were accurate to within a half degree! Mayer was also the first to develop the “reflecting circle” – a complete circular instrument graduated to 720°. The reflection circle was a welcome addition, because at the time the technology did not had enough accuracy for surveying measurement. To reduce the error, they relied on making the average of three sequential readings over the circle, separated 120º from each other. A very cool instrument that preceded the sextant!

Are you ready for one last cometary object? Then get out there and capture NGC 2261 (RA 6:39.2 Dec +08:44). You’ll find it about 2 degrees northeast of star 13 in Monoceros. Perhaps you know it better as “Hubble’s Variable Nebula”?

Named for Edwin Hubble, this 10th magnitude object is very blue in appearance through larger apertures, and a true enigma. The fueling star, the variable R Monocerotis, does not display a normal stellar spectrum and may be a proto-planetary system. R is usually lost in the high surface brightness of the “comet-like” structure of the nebula, yet the nebula itself varies with no predictable timetable – perhaps due to dark masses shadowing the star. We do not even know how far away it is, because there is no detectable parallax!

Until next week? Keep your feet on the ground and your eyes on the skies! There’s even more about to happen…

This week’s awesome images are (in order of appearance): Artist’s conception of the Stardust spacecraft Credit: NASA / JPL , Sally Ride – Credit: NASA, M79 Credit: NOAO/AURA/NSF, Johann Tobias Mayer (historical image) and the Hubble Variable Nebula by John Chumack. We thank you so much!!

Greetings, fellow SkyWatchers! While the skies don’t change a whole lot from year to year, how you approach astronomy and what you can do with your “astronomy time” certainly does! We begin the weekend with a variable star and a great galaxy. Ready for more? Then why not tackle an historic learning project with Mars? No scope or binoculars? No problem. There’s still lots of cool things you can do when you know where to look! Whenever you’re ready, I’ll see you in the backyard….

Friday, January 8, 2010 – Tonight we begin by celebrating two births – first Johannes Fabricius (1587). In 1616 he returned from the Netherlands with a telescope to observe with his father David, the discoverer of Mira. The father – son team studied sunspots, and Johannes was the first to submit work on the Sun’s rotation. Precisely 300 years later (and on the anniversary of Galileo’s death), Stephen Hawking was born – who went on to become one of the world’s leaders in cosmological theory. Hawking’s belief that the lay person should have access to his work led him to write a series of popular science books in addition to his academic work. The first of these, “A Brief History of Time”, was published on 1 April 1988 by Hawking, his family and friends, and some leading physicists.

Tonight let’s honor both men as we start with Mira for the unaided eye, binoculars or a telescope. Located in the heart of Cetus the Whale, Mira is one of those variables that even when well placed above the horizon, you can’t always count on it 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).

Now for the black hole! All you’ll need to do is starhop about three fingerwidths northeast of Mira to Delta Ceti. About one degree to the southeast you will discover M77. At magnitude 10, this bright, compact spiral galaxy can even be spotted with larger binoculars as a faint glow and is unmistakable as a galaxy in smaller scopes. Its small bright nucleus shows well in mid-sized scopes, while larger ones will resolve out three distinctive spiral arms. But this “Seyfert” Galaxy isn’t alone… If you are using a larger scope, be sure to look for 11th magnitude edge-on companion NGC 1055 about half a degree to the north-northeast, and fainter NGC 1087 and NGC 1090 about a degree to the east-southeast. All are part of a small group of galaxies associated with the 60 million light-year distant M77.

Saturday, January 9, 2010 – Tonight we’re all about Mars. We have precisely 3 weeks to go until opposition – meaning Mars rises as the Sun sets and will be visible all night. This means the Red Planet is very well placed for observing at a convenient time and it’s high time we learned to do some things the “old fashioned way”! Every couple of years Mars comes close enough to Earth for amateur astronomers to do something interesting… measure its distance from Earth using the original method of parallax. The first experiment first carried out by David Gill in 1877 on Ascension Island and now we can do the same from our own backyard. But let’s start with a little history, shall we?

Gill was originally a watchmaker and his love of precision instruments led him into astronomy. Even in those times, employment was scarce… So Gill and his wife set out for Ascension Island to improve the Observatory and measure the solar parallax by observing Mars. But, as all astronomers know, you don’t make a date with the sky – it makes a date with you… and things weren’t about to go easy. From Mrs. Gill’s journal:

“Tonight Mars will be nearer to us – his ruddy glare brighter than ever again for a hundred years, and what if we should not see him? The sun had shone all day in a cloudless sky, but before sunset some ugly clouds rolled up from windward… Six o’clock, and still the heavens look undecided; half-past six, and a heavy cloud is forming in the south. Slowly the cloud rises – very slowly; but by-and-by a streak of light rests on the top of the dark rocks – it widens and brightens, and at last we see Mars shining steadily in the pure blue horizon beneath… How slowly the minutes passed! How very long each little interruption appeared! The wind was blowing lazily, and light clouds glided at intervals across the sky, obscuring, for a few moments, the Planet as they crossed his path. But at last I heard the welcome note “All right,” and then I went to bed, leaving David to add the pleasant postscript of “Evening success” to his letters. When the letters were finished, he gave them in charge to Hill, with orders that they should be sent off at daybreak, and then he lay down to rest.

My husband would, of course, remain in the Observatory for the rest of the night to watch for clear intervals, while I was expected to go to sleep. But how could I? I took up a book and tried to read by the light of my lantern for a few minutes; then I thought to myself, “Just a peep to see whether the cloud promises to clear off.” I looked forth, and lo! no cloud! I rubbed my eyes, thinking I must be dreaming, and pulled out my watch, to make sure I had not been asleep, so sudden was the change. No! truly the obnoxious cloud had mysteriously vanished, and the whole moonless heavens were of that inky blueness so dear to astronomers. While my eyes drank in this beautiful scene, my ears were filled with sweet sounds issuing from the Observatory, “A, seventy and one, point two seven one; B, seventy-seven, one, point three six eight,” Let not any one smile that I call these sweet sounds. Sweet they were indeed to me, for they told of success after bitter disappointment; of cherished hopes realised; of care and anxiety passing away. They told too of honest work honestly done – of work that would live and tell its tale, when we and the instruments were no more; and, as I thought of this, there came upon me with all their force the glowing words of Herschel: “When once a place has been thoroughly ascertained, and carefully recorded, the brazen circle with which that useful work was done may moulder, the marble pillar totter on its base, and the astronomer himself survive only in the gratitude of his posterity; but the record remains, and transfuses all its own exactness into every determination which takes it for a groundwork.”

Gill’s work with Mars was such a success that it redetermined the distance to the sun to such precision that his value was used for almanacs until 1968. He went on to photograph the southern sky and helped initiate the international Carte du Ciel project to chart the entire sky. Now, thanks to the efforts of Brian Sheen of Roseland Observatory and John Clark Astronomy, you can easily participate in the same kind of historic project or get the correct information to “do it yourself” with your classroom or astronomy club.

The project involves photographing Mars and nearby stars – images taken at the same time from a number of different locations around the globe. John Clark is prepared to undertake the mathematical analysis or will provide the method for those wishing to do this themselves. All they are asking is for those groups and individuals who normally take images of stars and planets to contact the Observatory and they will provide you will all the detailed information to get in on the Mars action!

Sunday, January 10, 2010 – On this date in 1946, Lt. Col. John DeWitt, a handful of full-time researchers, and the U.S. Army’s Signal Corps were about to become the first group to successfully employ radar to bounce radio waves off the Moon. It might sound like a minor achievement, but let’s look into what it really meant.

Believed impossible at the time, scientists were hard at work trying to find a way to pierce Earth’s ionosphere with radio waves. Project Diana used a modified SCR-271 bedspring radar antenna aimed at the rising Moon. Radar signals were broadcast, and the echo was picked up in exactly 2.5 seconds. Discovering that communication was possible through the ionosphere opened the way to space exploration. Although a decade would pass before the first satellites were launched into space, Project Diana paved the way for these achievements, so send your own ‘‘wave’’ to the late rising Moon tonight!

Let’s also note the 1936 birth of Robert W. Wilson, the co-discoverer (along with Arno Penzias) of the cosmic microwave background. Although the discovery was a bit of a fluke, Wilson’s penchant for radio was no secret. As he once said, ‘‘I built my own hi-fi set and enjoyed helping friends with their amateur radio transmitters, but lost interest as soon as they worked.’’ But don’t you loose interest in the night sky! Even if you don’t use a telescope or binoculars, you can still look towards Cassiopeia, which contains the strongest known radio source in our own galaxy – Cassiopeia A.

Although traces of the 300-year-old supernova can no longer be seen in visible light, radiation noise still emanates from 10,000 light-years away – an explosion still expanding at 16 million kilometers per hour! So, where is the source of this radio beauty? Just a little bit north of the constellation’s center star.

Until next week? Have fun learning!

This week’s awesome image (in order of appearance) are: Stephen Hawking (public domain photo), Mira courtesy of SEDS (contributed by Jack Schmidling), M77 courtesy of NOAO/AURA/NSF, David Gill (historic image), Mars Hubble Photo, Ascension Island Map (Library on Congress – David Weaver), Mars Retrograde Animation courtesy of Arizona State University, Mars Horizon Map courtesy of Your Sky, Project Diana (public domain image), Cassiopeia A courtesy of Spitzer. We thank you so much!