For the last several years it has been my great pleasure to bring you this weekly column. If you thought this year was good - wait until you see the next! You've got it... "The Night Sky Companion" is now out in print! Unfortunately it won't be available as a free download, nor can I reveal what all that's in it... But won't you consider buying a copy? You can find it here at Amazon.com! I sincerely appreciate your support and I would love to hear your comments about the improved research and new illustrations. You'll find it far outshines the last! Also be sure to check any internet resource or your local bookstore for "The Night Sky Companion" and look for "On Rivers of Light", the latest book about the aurora with photos by Terry Mann!
Now, without further ado? Let's rock the night...
2008 Winter Astronomy Highlights
January - Greetings, fellow SkyWatchers! As we begin our observing year together on January 1, 2008, why not start before dawn this morning with a look at bright Spica and the Moon? You'll find the pair separated by around a fingerwidth as they rise together ahead of the first day of the New Year. On this night in 1801, the skies were clear in Italy and astronomer Giuseppe Piazzi was busy at the eyepiece. He had made a discovery - the first known asteroid. Unlike modern communications, Piazzi's mailed observations failed to reach others for confirmation before his new discovery had moved too close to the Sun, and the object was lost until its return in September. What we now know as minor planet Ceres was relocated thanks to Gauss and his method of calculating orbits. Ceres was identified again on the last day of 1801 and reconfirmed on this date in 1802. Why not try your own hand at locating Ceres? All it takes is an accurate locator chart readily available online. Even smaller telescopes can easily spot this bright solar system member this evening as it cruises about a fistwidth northeast of Alpha Ceti (Menkar).
But Piazzi wasn't the only astronomer to start the New Year with a discovery: Sir William Herschel was also at the eyepiece on this night in 1789! Turn your eyes toward Orion and the easternmost star in the "belt" - Zeta Orionis. Named Alnitak, it resides at a distance of some 1600 light-years, but this 1.7 magnitude beauty contains many surprises for the telescope user. It is a triple star system. Fine optics, high power and steady skies will be needed to reveal its members. Look about 15' east and you will see that Alnitak also resides in a fantastic field of nebulosity which is illuminated by our tripartite star. NGC 2024 (RA 05 41 43 Dec 01 50 30) is an outstanding area of emission discovered by Herschel on this night and cataloged as H V.28. At roughly magnitude 8, it is viewable in smaller scopes but will require a dark sky. So what's so exciting about a fuzzy patch? Within it are hot, young stars producing the radiation to illuminate the gaseous nebula. It is being compressed and the atomic density is increasing. It has begun to fragment, forming clumps. Over thousands of years it will collapse under the weight of its own gravity, superheating, and forming protostars. As the "Flame" heats up, fusion occurs and new stars are born. Depending on the fragmentation process, they may be small, red dwarves - or giant blue stars exerting their influence on the gases around them. Because of the density of NGC 2024, studies must be performed in infrared to see what lies below the surface, but larger telescopes will deeply appreciate this nebula's many dark lanes, bright filaments and unique shape.
In the early morning hours of January 4, be sure to keep a watch for members of the Quadrantid meteor shower. Its radiant belongs to an extinct constellation once known as Quadran Muralis, but any meteors will seem to come from the general direction of bright Arcturus and Boötes. This is a very narrow stream, which may have once belonged to a portion of the Aquarids. As Jupiter's gravity continues to perturb the stream, another 400 years may mean this shower will become as extinct as the constellation for which it was once known.
Up before dawn on January 5? Then you're in for a special treat as the thin crescent of the waning Moon pairs with Antares. Separated by less than half a degree, this could mean an occultation event for some observers. Be sure to check IOTA (International Occultation Timing Association) for accurate information.
On January 7, 1610, Galileo discovered three of Jupiter's four largest satellites using his simple telescope. This revelation changed the face of an Earth-centered Universe. This morning before dawn, why not take out your binoculars and see if you, too, can discover the "Galilean moons" with simple equipment. You'll find the largest of all the planets in our solar system making a wonderful morning apparition along the very last remaining curve of the Moon. Because it is so near the Sun, use caution - but don't worry if you can't spot it now. It will race further and further away from our nearest star in the weeks ahead!
On January 11, 1787, Sir William Herschel discovered two of Uranus' many moons - Oberon and Titania. As luck would have it, a moon and an outer planet will figure high on our observing list as well, because the tender crescent of our own Moon is less than half a degree north of Neptune! An appearance this close could mean an occultation event, so be sure to visit IOTA for accurate information for your area.
Very early on the morning January 18th, the Moon will be very near the Pleiades. This will be the first of a series of possible occultations of the Seven Sisters this year. IOTA has a page specifically devoted to occultations by the Pleiads (mostly for North America), so be sure to visit their site for details and maps of all of them.
Simon Mayr was born January 20, 1573. Although Mayr's name is not widely recognized, we all recognize the names he's given. Mayr observed the moons of Jupiter at nearly the same time as Galileo, and he was the one who assigned them the Greek names in use today. If you're up before dawn on his birthday, look for Jupiter and see if you can spot Europa, Io, Ganymede and Callisto and for yourself! They will all be to the west of Jupiter this morning, strung out in the order listed. Europa is closest, just 36" away, and Callisto is the furthest, 6' 42" west of the mighty planet. While you're out, take a few minutes to watch the skies for the peak of the Coma Berenicid meteor shower. Although the activity for this one is fairly weak, with an average fall rate of about seven per hour, it still warrants study. So what makes this particular shower of interest? Noted first in 1959, the stream was eventually tied in 1973 to another minor shower in the same orbit, known as the December Leo Minorids. As we know, meteoroid streams are traditionally tied to the orbit of a comet, and in this case the comet was unconfirmed! Observed in 1912 by B. Lowe, an Australian amateur astronomer, the comet was officially designated as 1913 I and was only seen four times before losing it to sunrise. Using Lowe's observations, independent researchers computed the comet's orbit, but it was basically forgotten until 1954. At that time, Fred Whipple was studying meteoroid orbits and made the association between his photographic studies and the enigmatic comet Lowe. By continuing to observe the annual shower, it was deduced that the orbital period of the comet was about 75 years, but the two major streams occurred about 27 and 157 years apart. Thanks to the uneven dispersion of material, it may be another decade before we see some real activity from this shower, but even one meteor can make your day!
January 22 is the Full Wolf Moon. Its name comes from the North American Indians who would hear the wolves howling in search of food in the cold, snow-covered and barren landscape. In Europe it was referred to as the Moon after Yule, and 388 years and 18 days ago, Galileo Galilei changed the face of astronomy when he observed it. Pointing his newly developed telescope at our nearest celestial neighbor, his observation of mountains and craters on the surface opened the world's eyes to what lies just beyond the range of human sight. Said Galileo, "It is a beautiful and delightful sight to behold the body of the Moon." Tonight discover for yourself what Galileo saw. Using any type of optical aid, trace the bright lunar rays extending from the brilliant Tycho or the deep impact of Copernicus.
On January 23, 2004 a young backyard astronomer named Jay McNeil was checking out his new 3" telescope by taking some long exposures of M78. Little did Jay know at the time, but he was about to make a huge discovery! When he later developed his photographs, there was a nebulous patch there which had no designation. When he reported his findings to the professionals, they confirmed its novelty and realized that Jay had stumbled onto something quite unique! It is believed that Jay's discovery was a variable accretion disc around a newborn star - IRAS 05436-0007. Little is known about the region, but it seems it had been caught in a photo once in the past but never studied. Even the Digital Sky Surveys had no record of it! Although Jay's discovery might not be bright enough on January 23 to be seen just south of M78, it is a variable and circumstances play a big role in any observation. Before you assume being a backyard astronomer has no real importance to science, remember a teenager in a Kentucky backyard with a 3" telescope...catching what professionals had missed!
On January 26, 1962, the US space program launched a lunar probe named Ranger 3. Its mission was to image the Moon right up until impact, land a seismometer, study gamma rays and report on surface reflectivity of radar... But, it didn't happen. Two days after launch, the ill-fated Ranger 3 was on a runaway course toward the lunar surface when it received an erroneous command and lost contact with Earth. As a result, it overshot its mark by 36,800 kilometers and still remains in heliocentric orbit. If you're up before dawn this morning, have a look at the Moon. Not only is Ranger 3 still up there, but you'll find Saturn quite close to it as well!
February - SkyWatcher Alert! Be sure to set your alarm for before local dawn on February 1. This morning Venus and Jupiter will be separated by less than a degree and will make a stunning sight which requires no special equipment to enjoy. Not to be outdone, the Moon and Antares are also less than a degree apart, and this could be an occultation event. Be sure to check IOTA for accurate information in your area. Wishing you clear skies!
On February 4 morning, discover some of the most beautiful celestial scenery you'll encounter all year as the crescent Moon, Jupiter and Venus all dance together in the pre-dawn skies. This one will be worth getting up early for!
If you're in the mood to travel on February 7, the place to be is in the Southern Hemisphere - especially Antarctica! An annular solar eclipse will be visible over part of Antarctica, while a partial eclipse will be viewable for all of New Zealand and a portion of eastern Australia. For these lucky observers, the next two nights will be the peak of the Centaurid meteor shower. Discovered by Michael Buhagiar of Australia, this stream has two radiants - Alpha and Beta. While both occur at roughly the same time and roughly from the same place, tonight's Alpha peak has a regular fall rate of around three per hour and an average magnitude of 2.4; while tomorrow's Beta stream produces up to 14 per hour, and they are far brighter at magnitude 1.6. Wishing our mates clear skies for these events!
February 12 marks the anniversary (2001) of NEAR landing on asteroid Eros. The Near Earth Asteroid Rendezvous mission was the first to ever orbit an asteroid, successfully sending back thousands of images. Although it was not designed to land on Eros, it survived the low speed impact and continued to send back data. And where is asteroid Eros? You'll find our 11.3 magnitude friend scooting along through the southern reaches of Pisces about ten degrees North-northwest of Uranus. It's close to the western horizon at skydark, so don't wait too late!
February 21... Are you ready for tonight? Beginning at 00:34:59 UT, the Moon will begin to slide inside the Earth's penumbral shadow. You got it... It's time for a lunar eclipse! Although the beginning passage is the most subtle part of the event, it will be visible in western Asia, Europe and Africa about the time the Moon sets. For observers in the Americas and the Pacific region, this gentle shading will end around the time the Moon rises. At 01:42:59 UT, the Moon will pass into the deep umbral shadow and not leave until 05:09:07 - this is the time frame of partial eclipse. Totality will occur for the Americas, Europe, Africa, the Middle East and western Asia, beginning at 03:00.34 UT with maximum at 03:26:05 and end at 03:51:32. Considering the umbral magnitude is estimated at 1.1, this should make for a deep orange color and will be quite worth taking the evening to observe. Take the time to try your hand at photography and make notes. Estimate the eclipse by the Danjon scale: L=4 is an orange or coppery color with a blue tint where the umbral and penumbral shadow meets. L=3 is brick colored, with a gray or yellow rim. L=2 is a deep red and the Moon will be very dark in the center. L=1 is a dark eclipse. The Moon will appear brown or dark grey, while the surface features will be hard to see. L=0 is so dark the Moon is nearly invisible. Power up with a telescope to watch a rare treat as the shadow advances over the craters, mountains and seas... And then the Sun rises over them again! But don't get so wrapped up in the eclipse that you forget to take a look around the Moon. For many observers, bright Regulus will be less than a degree away from the lunar limb and a lucky few will also get to witness either a grazing event or an occultation on this same night! Be sure to scan around with binoculars to have a look at other objects as well. How often can you see a DSO on a night lit by the Full Moon? Wishing you clear skies...
Celestial Scenery Alert! Be sure to set your alarm for just before local dawn on February 26. This morning the two innermost planets - Venus and Mercury - will grace the eastern sky just about one degree apart.
February 29... It's Leap Year! Celebrate today by beginning with observations of the Moon and Antares. For most viewers, the pair will be around a half a degree apart, but for a lucky few this could mean an occultation or grazing event. Be sure to check with a reputable source, such as IOTA, for accurate times and locations.
March - On March 1, 1966 Venera 3 became the first craft to touch another planet as it impacted Venus. Although its communications failed before it could transmit data, it was a milestone achievement. If you're up before dawn, be sure to have a look a Venus and say Spaseba! George Abell was born on this day in 1927. Abell was the man responsible for cataloging 2712 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 their distances. Abell also discovered a number of planetary nebulae and developed the theory (along with Peter Goldreich) of their evolution from red giants. Abell was a fascinating lecturer and a developer of several television series dedicated to explaining science and astronomy in a fun and easy to understand way. He was also president and a member of the Board of Directors of the Astronomical Society of the Pacific, and he served in the American Astronomical Society, and was a member of the Cosmology Commission of the International Astronomical Union. And he accepted editorship of the Astronomical Journal just before he died. To celebrate Abell's achievements, I can think of no finer area of the sky than one of his own galaxy clusters - A 1367 - located about a degree southwest of 93 Leonis (RA 11 44 44 Dec +19 41 59). Centered on 13th magnitude NGC 3842, this is an area of challenging intrigue spanning a degree of sky. It contains as many as two dozen small galaxies which can be seen with a large telescope, but will require very fine skies and patience to identify its many members. A 1367 is in an area of sky which many astronomers return to year after year, and it is a gemstone for the galaxy collector.
If you're up before dawn on the morning of March 3, be sure to take a look at the close appearance of Jupiter and the Moon. While the pair is still well separated, they make a pleasing sight! Also look at the eastern skyline for Mercury. It's now reached its greatest elongation. Has its relative position near Venus changed over the last few days?
March 5... Celestial Scenery Alert! The place to be is outdoors just before local dawn to watching the beautiful apparition of the rapidly waning Moon, Venus, and Mercury. The inner planets are not only dancing very close together but are less than half a degree from the Moon's limb for almost all observers. For some, this is bound to be an occultation event, so be sure to check IOTA for accurate times and locations. Although daylight will rob the view, only hours later the Moon will occult Neptune as well!
On March 13, 1781, Uranus was discovered by William Herschel. Also on this day, in 1855, Percival Lowell was born in Boston. Educated at Harvard, Lowell went on to found the observatory which bears his name in Flagstaff, Arizona, and spent a lifetime studying Mars. Tonight, you can honor Lowell by looking at Mars yourself. While you might not see a great many details, think of how many strides have been made since Lowell's time and how advanced our knowledge of Mars has become! Look for Mars hauntingly close to the Moon on March 15!
On March 19 the gibbous Moon will be almost overpoweringly bright, but that doesn't mean there isn't something fun to do! For most observers, Regulus will be less than a degree away from the lunar limb and Saturn about twice as far. For a lucky few, Regulus could be either an occultation or grazing event, so be sure to check sources like IOTA for precise times and locations!
If you're up before dawn on March 20, be sure to check out the eastern horizon for the return of the swift inner planet Mercury. Watch in the days ahead as it rises higher and higher each morning on its climb toward Venus! Today is Vernal Equinox, one of the two times of the year when day and night become equal in length. From this point forward, the days will become longer - and our astronomy nights shorter! To the ancients, this was a time of renewal and planting - led by the goddess Eostre. As legend has it, she saved a bird whose wings were frozen from the winter's cold, turning it into a hare which could also lay eggs. Do you have children or grandchildren? Tonight would be a great night to show them the "Rabbit in the Moon!" Since the dawn of mankind, we have been gazing at the Moon and seeing fanciful shapes in the lunar features. Tonight as the Moon rises is your chance to catch the "Rabbit," which is a compilation of all the dark maria. The Oceanus Procellarum forms the ear while the Mare Humorum makes the nose. The Rabbit's body is Mare Imbrium and the front legs appear to be Mare Nubium. Mare Serenitatis is the backside and the picture is complete where Mare Tranquillitatis and Mare Fecunditatis shape the hind legs - with Crisium as the tail. See the Moon with an open mind and open eyes…and find the Rabbit!
Although the Moon will greatly interfere on March 22, enjoy a spring evening with two meteor showers. In the northern hemisphere, look for the Camelopardalids. They have no definite peak, and a "screaming" fall rate of only one per hour. While that's not much, at least they are the slowest meteors - entering our atmosphere at speeds of only seven kilometers per second! Far more interesting to both hemispheres will be the March Geminids which peak tonight. They were discovered and recorded in 1973 and then confirmed in 1975. With a much faster fall rate of about 40 per hour, 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?
If you're up before dawn the morning of March 24, grab your binoculars and have a look at the intricate dance of orbits as Mercury passes Venus in the brightening skies!
Set your alarm clock for the early morning hours of March 27 as red Antares and the waning Moon slow dance together on the ecliptic plane less than a degree apart! A union this close usually means an occultation for some part of the world, so be sure to check sources such as IOTA for accurate information in your area.
March 28, 1749 is the birthday of Pierre LaPlace - the mathematician who conceived both the metric system and the nebular hypothesis for the origin of the solar system. Also born on this day 1693 was James Bradley, an excellent astrometrist who discovered the aberration of starlight (1729) and the nutation of the Earth. And, in 1802, Heinrich W. Olbers discovered the second asteroid, Pallas, in the constellation Virgo while making observations of the position of Ceres, which had only been discovered fifteen months earlier. Five years later on this same date in 1807, Vesta - the brightest asteroid - was discovered by Olbers in Virgo, making it the fourth such object found. Your assignment, should you choose to accept it, is to locate Vesta. You'll find it just a bit south of the union of Uranus, Venus and Mercury about 30 minutes before local dawn. Pallas is too close to the Sun right now for safe viewing. While asteroid chasing is not for everyone, both Vesta and Pallas are often bright enough to be identified with just binoculars. In the coming months, each will rise higher each morning in the predawn sky. Use an online resource to get accurate locator charts and keep a record of spotting these solar system planetoids!
If you're out late or up before sunrise on March 30, be sure to take a look at the Moon and Jupiter making a pleasing pairing along the ecliptic. No special equipment is needed!
May all your journeys be at light speed... ~Tammy Plotner.