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The DAAC MONTHLY CALENDAR OF EVENTS
March 2009
The Solar System : Mercury - Mercury is peeking out over the eastern horizon in mid-March on March 5 it is paired with VENUS (much brighter) along with the very thin crescent moon in bright dawn skies. During mid-March Mercury would be a fairly favorable opportunity to glimpse the planet, with somewhat redder Mars nearby; Mercury appears about "nearly full" (about 94% illuminated) when viewed in a small telescope. Look for this elusive planet only about 6 degrees to the lower left of much brighter and yellow JUPITER - in AQUARIUS Venus - Venus is now very low in the southwestern dusk skies, setting only two hours after the sun. However, this may be the BEST opportunity for our generation to view this magnificent planet. During the latter part of the month, Venus attains its maximum possible size - almost 1 arc minute, or about 1/30th the size of the full moon - and this size can possibly be detected fully with the naked eye.....revealing Venus as a splendid tiny crescent, like a thin crescent moon. This is certainly visible in even the smallest binoculars and in telescopes. For evening viewing this month, do not wait too late: view about 30 minutes after sunset in SW skies. Venus will likely disappear from the evening skies for our viewing on or about March 20-24, when it will be too close to sunset to view....however, it will reappear quickly in MORNING skies by about the same time, in the ENE skies about 10 minutes before sunrise, rising a bit earlier each night into April....as April approaches, the size of Venus will continue to increase slightly until about April 4, after which the crescent will be somewhat brighter and more illuminated, but beginning to very slightly decrease in size each morning. NOTE that it might be possible to see Venus BOTH in the morning and evening skies on the dates between March 21 and March 24. in CAPRICORNUS Mars - A very disappointing beginning to Mars in 2009, with the planet very, very low in southeastern skies in strong dawn twilight, rising only about an hour ahead of the sun at midmonth. HOWEVER - be sure to mark your calendar for the early morning of March `1 when Mars and Mercury will be less than ONE DEGREE apart with brilliant JUPITER above them. About 30 minutes before sunrise is ideal - In AQUARIUS Jupiter - After spending several weeks in conjunction with the sun in early 2009, Jupiter has now re-emerged strongly into the dawn eastern skies; look for the mightiest of planets to rise in the east about an hour before the sun; telescopically, Jupiter is very disappointing this month, but will increase its lure throughout the summer of this year. - In CAPRICORNUS Saturn - The ringed planet is now high in the eastern sky at dark, and very favorably placed for telescopic views of its magnificent ring system by 10 p.m. local time. The rings are very much "closed" in their angle to the earth, presenting an almost linear appearance, tilted between 2 and 3 degrees all month. Saturn reaches opposition (see Calendar below) on March 8; it will rise at near sunset on that date, be overhead and very favorably placed for viewing at midnight, and will set about the time the sun rises the next morning, providing a Saturn-filled evening of observations. It is now near the lower right foot of the great lion, LEO. - in LEO Uranus - This distant planet is just past conjunction with the sun and is not favorably viewable in March 2009 - in AQUARIUS. Neptune - Those with large telescopes might be able to glimpse this distant planet in evening twilight, very low in the SW sky at dusk - in CAPRICORNUS. Pluto - Now in southern skies viewable far in the SSE skies during morning hours, rising about five hours ahead of the sun; a telescope is needed to view this 14th magnitude distant planet - In southern OPHIUCHUS note: to locate the three outer planets, we recommend you use the charts from a good planetarium PC program! ALSO see page 63 of the September, 2008 Sky & Telescope Magazine for yearly details!
Observable
Comets: Comet C/2008 J1 (Boattini) - this 17th magnitude comet continues to grace the skies pretty much all night in the circumpolar northern constellation of Perseus; this active comet continues to deserve attention by both visual and CCD astronomers, and has demonstrated a highly elongated strong coma and possible sunward anti-tail....still is well worth watching! This is only one of the three "Boattini Triplet" comets this month. Comet P210 (Christensen) - Previously come P2008 X4, this now numbered periodic comet is magnitude 15 in the constellation of Serpens this month, favorably placed for low latitude observers around midnight. Comet C/2006 OF2 (Broughton) - Probably the most impressive telescopic comet of winter, a comet which continues to impress us at DAAC; it is high overhead, although it transits highest at about midnight local time; it too is circumpolar and could reach magnitude 10 this February in the constellation of Auriga. Look for a nice curving tail at this time.
Comet P85 (Boethin) - try to find this one....this elusive comet has thus far evaded us and has not been seen for some time; it SHOULD be 10th magnitude in the constellation of Taurus at this time, but searches have not revealed it. Eitehr it is far fainter than expected, or far from the predicted position. Last seen in 1986! Comet P67 (Churyumov-Gerasimenko ) - a fine comet with both a dust tail and now an anti-tail, seen developing in early January, now in the constellation of Aries, overhead at about sunset local time; this comet has outshined its predictions and is well worth watching in early winter skies.Comet P29 (Schwassmann-Wachmann) - Once again proving to be a very active comet, this continually changing comet has had another outburst in January, reaching an unexpected magnitude of nearly 8; watch for potential fragmentation of this comet and some spectacular morphological changes.
Comet P65 (Gunn) - This comet rises in the east before midnight and transits mid-morning in the constellation of Virgo; it is a very well defined comet and has been observed with a short tail and well formed coma since December. Look for this comet to be mingled with MANY nice galaxies in the nearby field throughout its sweep of stars in March. Comet P116 (Wild) - Another nice telescopic comet, overhead about midnight in the constellation of Cancer; this comet shows a compact coma with nucleus, short tail and is at magnitude 12 this month.Comet P144 (Kushida) - Progressively moving eastward, this comet has now moved into Gemini and is high overhead at 10 p.m. local time and visible late into morning. Now at 12th magnitude, the comet is very large and continues to impress both visual and photographic enthusiasts. Comet P77 (Longmore) - A very nice telescope comet, one that has been observed since December now located in a galaxy-rich field in the constellation of Coma Berenices, this comet is expected to peak at about magnitude 16.0 this month.Comet C/2008 A1 (McNaught) - This has been a spectacular comet in southern skies, but now will grace northern skies for a while. Embedded in the very rich clouds of the Cygnus Milky Way, this comet rises about midnight in the NE skies. and is high in the skies at dawn. Although predicted to be only magnitude 12, this comet still should be a nice comet telescopically for northern observers.
HAVE YOU SEEN THE MYSTERIOUS ZODIACAL LIGHTS? One of the most awe-inspiring sights of my late childhood was the night in 1962 that I spotted the elusive "Zodiacal Light" for the first time....and totally accidentally. This strange glow was protruding from the dusky, nearly dark, far western horizon from atop Petit Jean Mountain, then in very dark skies in a rural, unlighted America.
Like your first view of Saturn through a telescope, you will never forget seeing this phenomenon. Orbiting the sun is a huge disk of interplanetary debris, tiny particles and dust left from countless collisions throughout the past billions of years between asteroids, comets and perhaps even major planets. Like any object in the solar system, they reflect light and this great dusty "mirror" can shine a very vague light that can be seen from Earth best during the two Equinoxes: Spring and Fall. This is because the plane of our ECLIPTIC (the plane in which the planets orbit the sun) is perpendicular to both east and west horizons at dawn and dusk, respectively during the equinoxes, and hence this light projects upward into the sky for as much as 50 degrees. You MUST have very dark skies and unlighted horizons to both east and west to see this phenomenon; look for the Zodiacal Light in the morning toward the EAST of course, and emanating from the WEST horizon after evening dusk darkens. The light is very, very vague and many times will appear as a streak of light projecting straight up from the horizon to nearly overhead. Some times, the light can appear as a blade of a knife cutting the darkness, while other times it might be a roundish cigar shape projecting upward. Look as soon as the sky gets dark (evening) or just before the first light of dawn (morning).For EVENING observations of the Zodiacal Light, concentrate during the weeks of February 23 through March 8; for MORNING glimpses, you are best to get up early during the weeks of March 23 through April 6. NOTE that the brilliant planet VENUS, now shining brightly in the SW evening skies, will add to the excitement and grandeur of the brilliance of the Zodiacal light. The DAAC March Star of the Month: ARCTURUS in Bootes Bright Star Arcturus (Alpha Bootis) "ark-TOUR-us" At magnitude -0.1, Arcturus is one of the few stars that can be found with your GO TO computer during daytime! After your eyes get accustomed to the bright background light of the finder scope, it is clearly visible when nearly overhead and far away from the sun's glare. Arcturus is huge - about 20 million miles across - and well over 100 times more luminous than our sun. METEOR SHOWERS for March 2008: Observe when the moon does not interfere and attempt to observe AFTER midnight for most meteors to be seen! During March, three primary meteor showers peak but none are on the order of which we could call "major events." However, as with a months and times during the year, observers should always be aware that new sporadic meteor showers can occur at anytime from seemingly unknown sources and radiants.
March 22 - Camelopardalid Meteors - Already high in the sky at dark, this meteor shower really has no definite peak, but a few meteors per hour can be seen coming from this very high northern meteor shower, only 22 degrees from the northern celestial pole; hence it is "up all night" for those braving the cold temperatures of March. Not only are there very few meteors to be seen from this rather dull shower, but the ones that ARE noticed travel the slowest across the sky of all known meteors....only about 7 kilometers per second! We see them as they begin to burn at an altitude of about 80 kms (~50 miles) above the Earth's surface. If you are interested, attempt to spot meteors from dark until about dawn but note that the absence of any light of the new moon will be favor this year's sighting of the maximum number of meteors. March 22 - March Geminid Meteors - A very favorable year for this meteor shower, since the moon will new and absent the sky all night....observe vigorously!! Discovered in only 1973 by amateur astronomers, much is still to be learned on this shower, so this is one where you can make a valuable contribution by observing. The radiant is high overhead for northern hemisphere observers at the time the sky truly gets dark, but because of bright moonlight, only the brightest meteors (if any) will be seen. When first discovered in Hungary, nearly 50 meteors per hour in a short-burst stream were seen and this was confirmed again with sightings in 1975. Like the Camelopardalids (above), the meteors in this stream are very slow and there is some possibility that the two showers could be linked to two diffuse clouds of debris from one parent object.
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