JANUARY 2006 �������������� http://www.universetoday.com �������������� TAMMY PLOTNER WITH JEFF BARBOUR 1 SUNDAY, JANUARY 1 Welcome to the New Year! 195 years ago this night, Italian Giuseppe Piazzi discovered the first asteroid- an object we know now to be a minor planet. He observed until illness stopped him on February 11th. Piazzi sent news of his discovery to other observers on January 24th, but by the time they were re- ceived, Ceres was too close to the Sun for observation and was lost. With help from Gauss’ refined method for calculating orbits, Ceres was finally recovered in Virgo on the last day of 1801 and reconfirmed on this date in 1802. GIUSEPPE PIAZZI As in Piazzi’s day, Ceres is far too close to the Sun now for observation, (PUBLIC DOMAIN IMAGE) but let’s start our year by exploring one of the most magnificent sights in the heavens - the “Great Orion Nebula.” Although seasoned observers already know how to find M42, perhaps you are just learning. Relax, because this is one of the easiest studies in the sky to find. Once your new telescope or binoculars are ready, avoid all light sources while waiting on the sky to get good and dark. Go out and face southeast. See those three bright stars in a row? They form the “Belt of Orion.” Now, hold your left hand out with your arm extended as far as possible. The constellation of Ori- on is quite large and your hand spans about 20 degrees of sky. If you cover the “Belt” with your palm, the bright red star at the tip of your little finger is Be- telgeuse and the bright blue star by your thumb is Rigel. Congratulations, you’ve learned a lot in just a few minutes! M 4 2 : Now look again at the belt of Orion and give it a “thumbs up.” About a “THE GREAT ORION NEBULA” CREDIT: R. JAY GABANY thumb’s length below it is a curved line of dimmer stars. Good job! This is Ori- on’s “Sword.” If skies are dark, you will see a faint, glowing patch in the center of this area. Now, aim your telescope or binoculars there... The Great Orion Nebula is one of the most breathtaking sights in the sky and holds a wealth of fine details. Great swirls and whorls of fluorescent nebula fan their way outwards across the field of view. Later, we’ll explore its many �������������� riches, but for now... Welcome to the Night Sky and prepare to journey with us http://www.universetoday.com as we explore together throughout the year. �������������� 2 WHAT’S UP 2006: 365 DAYS OF SKYWATCHING MONDAY, JANUARY 2 In 1959, the USSR launched the very first Moon probe. Named Luna 1, it was the first craft to leave Earth’s orbit. Although the slender crescent Moon is low on the eastern horizon, we can still look at the lunar surface. Just slightly lunar south of center where light and shadow meet (the terminator), look for large crater Humboldt. Stretching 125 miles in length and reaching a depth of 15,400 feet, this excellent old crater will show a dark, inner east wall that runs almost parallel to the terminator. Since the Moon will set quickly, we’ll have early evening dark skies. Let’s LUNA 1 - CREDIT: NASA take this opportunity to explore a distant galaxy much like our own - M74. Located about a finger-width east-northeast of Eta Piscium, this large spiral galaxy was first discovered by Pierre Mechain in 1780. M74 is pos- sibly one of the faintest and most elusive of the Messier objects and it’s a challenge for small telescopes with its low surface brightness and a dis- tance of 43 million light-years. With mid-sized scopes, expect nothing more than a faint, round glow from this galaxy - but larger scopes will reveal a condensed nucleus and hints of faint swirling spiral arms. M74 - CREDIT: R. JAY GABANY �������������� http://www.universetoday.com �������������� TAMMY PLOTNER WITH JEFF BARBOUR 3 TUESDAY, JANUARY 3 Tonight the waxing Moon will be a bit higher above the horizon. This will give us a splendid opportunity to study it. Let’s begin with binoculars and start by identifying the partially disclosed Mare Crisium just lunar north of center along the terminator. Seen along the curve of the surface, our emerging mare doesn’t look large, but it’s actually the size of the state of Washington. If you are using a telescope, look along the eastern edge of its walls. Roughly to the middle, you will see two small craters - Alhazen to the north and Hansen to the south. When the Moon sets, we have an opportunity to do some deep sky observing. Let’s focus our attention on M77. Located less than a finger-width southeast of Delta Ceti, this 10th magnitude spiral is bright, compact and within small scope range. M77 is a member of a galaxy group including NGC 1055, NGC 1073, NGC 1087, and NGC 1090. The bright, inner spiral pattern around the nucleus of M77 is easily resolved by large scope, but you might catch a glimpse through small scopes on a dark and steady night. For large aperture, many small knots and brightenings await you as you view this 60 million light-year distant galaxy! �������������� M77 - CREDIT: NOAO/ AURA/NSF http://www.universetoday.com �������������� 4 WHAT’S UP 2006: 365 DAYS OF SKYWATCHING WEDNESDAY, JANUARY 4 386 years ago on this night, Galileo Galilei began to make a series of obser- vations that revolutionized the study of the sky. Using his handmade refractor telescope of less than 2” aperture, Galileo saw craters and mountains on the Moon! Tonight let’s celebrate Galileo’s many achievements by taking our own lunar journey of discovery. Using binoculars, return to the Mare Crisium area and look just lunar north for spectacular Cleomides. This two million year old crater is separated from Crisium by some 60 kilometers of mountainous terrain. Telescopically, Cleo- GALILEO mides is a true delight at high power. Look for two small interior craterlets and a CREDIT: NASA surface crack called a rimae cutting diagonally through its northern interior. Can you spot small craters Debes and Trailes on Cleomides’ northwestern edge? Later tonight will be the perfect time to watch the Quadrantid meteor shower. Its source point, called a radiant, belongs to an extinct constella- tion - Quadrans - now associated with bright Arcturus and Bootes. The fall rate varies, but you might be able to spot around 60 per hour from a dark location. Look for trails that have a blue tint. MARE CRISIUM CREDIT: GREG KONKEL �������������� http://www.universetoday.com �������������� TAMMY PLOTNER WITH JEFF BARBOUR 5 THURSDAY, JANUARY 5 NGC 869 AND NGC 884: THE “DOUBLE CLUSTER” CREDIT: N.A. SHARP/NOAO/AURA/NSF Tonight let’s return to the lunar surface and begin our explorations using binoculars to identify Mare Fecunditatus - just lunar south of Mare Crisium. This “fertile sea” is an area around of the size of the state of California. Look on its eastern shore to see the flat, bright oval of Langrenus. This is an opportunity to challenge yourself by identifying two small craters just slightly northwest of the mare’s central point - Messier and Messier A - named for the famous French comet hunter. Keep them in mind, for in a few days you will see a pair of “rays” extending out from them. Now turn your binoculars or telescope towards one of the finest pair of star clusters in the sky. Look midway between the lazy “W” of Cassiopeia and the long backwards “J” of Perseus for the “Double Cluster.” Known more properly as NGC 869 and NGC 884, each of these “gatherings of stars” is a fine example of a galactic cluster and together they are outstand- ing. Noted in records from as early as 150 B.C., they are roughly 8000 light- years away, and contain many supergiant stars 10 times more massive than our own Sun! �������������� http://www.universetoday.com �������������� 6 WHAT’S UP 2006: 365 DAYS OF SKYWATCHING FRIDAY, JANUARY 6 The first atomic clock was built on this day in 1949. Based on theoretical work by Isidor Rabi and Norman Ramsey, it used ammonia as a “pendulum.” Eight years later, the first cesium beam device was built and its successors now keep time to one-millionth of a second per year. This type of accuracy makes possible high resolution radio interferome- try. It also tests Einstein’s theory of general relativity, runs the Global Positioning Satel- lite systems, and accurately determines the Earth’s changing rotation rate! On the lunar surface tonight, let’s look at Mare Serenitatus. On its northeast shore, binoculars will have no trouble spotting the shallow ring of crater Posidonius. Almost flat from eons of lava flows, this crater shows nu- merous variations in texture along its floor in small telescopes. Look a bit south of Posido- nius and almost parallel to the terminator for a curious feature known as the Serpentine Ridge. This thin, white line wanders across the western portion of Mare Serenitatus for a distance of about 250 miles. In some places it rises as high as 1000 feet above the smooth sands. This lunar “wrinkle” is an amazing 6 miles wide. While you’re out, why not try asteroid Vesta? It’s at opposition tonight and you can find accurate locator charts at THE SERPENTINE RIDGE CREDIT: RICARDO BORBA www.heavens-above.com. If you’re not too sure of which stellar point is the asteroid, try printing out the map and looking over a period of several night for which “star” moves.