Jimmy Westlake: Celestial highlights for 2010
December 27, 2009
Steamboat Springs — If I had to astronomically characterize year 2010, I would call it "The Year of Eclipses." We open the year with an eclipse, and we close out the year with an eclipse, with two other eclipses in between. But that's not the only excitement brewing in the stars in 2010. There's a big dipper full of beautiful and exciting celestial events to keep you looking up all year long. My complete day-by-day listing of cosmic events is included below, but allow me to condense the list down to my top 10 celestial events for 2010 in chronological order:
■ Jan. 15: Annular Solar Eclipse — The first of four eclipses in 2010 is an annular, or ring eclipse, of the sun. A ring eclipse happens when the Earth is near its closest point to the sun, so that the sun looks big in the sky, and the moon is near its farthest point from Earth, so that it looks small in the sky. Under these circumstances, the moon appears too small to totally cover the sun, leaving a ring of fire visible around the edge of the moon. At no time is a ring eclipse safe to look at without a protective solar filter. Unfortunately for us, this eclipse is only visible from a narrow swath of the Earth that begins in East Africa, crosses the Indian Ocean, and winds up in Southeast Asia. The annular solar eclipse of May 20, 2012, will come much closer to Colorado and offer us a chance to see a ring eclipse from right here in the American southwest. Still, if you find yourself in Sri Lanka on Jan. 15, pull out that solar filter and look up!
■ Jan. 29: Opposition of Mars — Once every 780 days, the Earth passes between Mars and the sun, placing the two planets as close together as possible. This alignment of worlds is called opposition. When Mars reaches opposition in January, it will be 62 million miles from Earth, its closest point for 2010. Mars will be shining brightly in the constellation of Cancer, very close to the Beehive Star Cluster. On the night of opposition, Mars will rise in the eastern sky right beside the full Snow Moon.
■ May 21: Venus passes 1/2 degree N of M35 Star Cluster — The planet Venus, our "evening star" for most of 2010, will glide past the glittering star cluster M35, at the feet of the Gemini twins, on May 21 after sunset. Although M35 is faintly visible to the unaided eye as a fuzzy smudge, you
will need a pair of binoculars or a small telescope to appreciate the beauty of the Queen of the Night gleaming beside the hundreds of glittering stars of M35. The telescope will reveal yet another, more distant star cluster, NGC 2158, at the edge of M35. Look west after dusk but before Venus sets at about 11 p.m.
■ June 20 and 21: Comet McNaught in night and morning sky — Comets are notoriously unpredictable in how bright they will become as they round the sun and begin to boil away and grow their tails. I'm going to go out on a limb and predict that Australian comet-hunter Rob McNaught's newest discovery, Comet McNaught C/2009 R1, will put on a nice show for us after sunset June 20 and again the next morning before sunrise June 21. The comet might be faintly visible with the unaided eye as it passes less than 2 degrees from the very bright star Capella in the constellation Auriga. Binoculars will enhance the view. Look northwest after sunset June 20 and in the northeast before sunrise June 21. If I am right, this could be an unforgettable view.
■ June 26: Partial lunar eclipse at dawn — Our second eclipse of the year is a partial eclipse of the moon, this one visible from Colorado. When the full Hay Moon rises at sunset June 25, it will look like any other gorgeous full moon, but beginning at 4:17 a.m., the northern half of the moon will pass into the Earth's dark shadow. The dark "bite" out of the lunar "cookie" will be greatest at 5:39 a.m., just as the moon sets in the northwest and the sun breaks the horizon in the northeast. From Northwest Colorado, most of this eclipse will be seen during morning twilight. It isn't every day that you get to see an eclipsed moon in a colorful predawn sky.
■ July 11: Total solar eclipse — The third eclipse of 2010 is the ultimate eclipse, a total eclipse of the sun. For this eclipse, the moon will appear slightly larger than the sun so that it can completely cover the sun's blinding disk for as long as 5 minutes and 20 seconds of totality. It is during these precious moments of totality that the sun's beautiful corona and chromosphere flash into view. Astronomers and eclipse chasers from across the globe will converge on the eclipse zone to spend these few minutes photographing, studying and just plain staring at what is arguably the most awesome sight in nature. But, alas, this spectacular eclipse is not visible from anywhere in North America. In fact, the moon's shadow will sweep across mostly open waters of the South Pacific, passing over a few exotic islands before sweeping across the southern tip of the South American continent. This is the last total eclipse of the sun visible anywhere on Earth until Nov. 13, 2012. July 2010 would be a great time to take that dream vacation to Tahiti.
■ Aug. 11 and 12: Perseid Meteor Shower — One of the most reliable of our annual meteor showers is the August Perseid shower. We experience this shower of "falling stars" every Aug. 11 and 12 when the Earth plows head-on into the dust swarm that fills the orbit of Comet Swift-Tuttle. If the sky is dark and clear, a single observer usually can count about 60 meteors per hour at the shower's peak in the predawn hours of Aug. 12. But don't expect to see exactly one meteor per minute. The Perseids shoot across the sky in brief flurries of two or three with several minutes of calm in between. Perseid meteor watching makes a great family event. Take the kids and find a nice, dark campground, roll out the sleeping bags and watch the fireworks. See who can count the most meteors or who can spot the brightest one. This year, the two-day-old moon will set shortly after the sun the night of Aug. 11, leaving the sky dark and perfect for meteor watching.
■ Nov. 4: NASA's Deep Impact spacecraft passes Comet Hartley 2 — Barring any new discoveries, the best naked-eye comet of 2010 is likely to be Comet Hartley 2. It was only discovered in 1986 and follows a relatively short 6.4-year orbit around the sun. On Oct. 20, Comet Hartley 2 will buzz by Earth at a distance of only 46 times the distance of the moon. Combine that with the comet's closest approach to the sun on Oct. 28 and the conditions are just right for us to have a very nice naked-eye view of Comet Hartley 2 during the last half of October and first half of November. Adding to the excitement, NASA's Deep Impact spacecraft is due to pass only 621 miles from the icy nucleus of Comet Hartley 2 on Nov. 4, taking measurements and snapping pictures. How cool will it be to stand outside and watch Comet Hartley 2 with your own eyes while images are being beamed back to Earth from the Deep Impact spacecraft? It's the kind of moment we star gazers live for. Stay tuned to the news as the date approaches.
■ Dec. 14: Geminid meteor shower — There was a lot of talk after the Geminid meteor shower in 2009 about the Geminids becoming stronger each year. Although Northwest Colorado was clouded over on the morning of the peak Dec. 14, observer reports from across the world revealed that the peak of the 2009 Geminid meteor shower exceeded even the most optimistic predictions. Meteors were shooting across the sky at a rate of more than 120 per hour. If the trend continues, we might be treated to an annual Geminid mini-storm in coming years. In 2010, the moon will set before 1 a.m. on the morning of Dec. 14, leaving the best meteor-watching hours dark and moon-free. So bundle up, break out the hot chocolate and watch the best meteor shower of the year.
■ Dec. 21: Total eclipse of the moon — The full moon that occurs before dawn Dec. 21, 2010, will be an unusual fourth full moon of autumn, for which there is no traditional name. The named moons of autumn — Harvest Moon, Hunter's Moon and Long Night Moon — already will have occurred. Such "nameless" full moons usually are dubbed "blue moons." This blue moon is even more exceptional because it will be totally eclipsed by the shadow of the Earth. All of North America will be perfectly placed to view the entire eclipse. The eclipse will begin at 12:32 a.m. and will progress until totality begins at 1:41 a.m. For 72 minutes, the full moon will look like a glowing orange ember against the starry sky as the reddened light of every sunrise and sunset on Earth is projected onto the moon. The moon will be positioned at the feet of the Gemini Twins, very close to the star cluster M35, which will play a role in several of my top 10 celestial events for the year. The binocular view of the dull, red full moon beside the glittering star cluster will be breathtaking. Totality will end at 2:53 a.m., and the moon will completely emerge from the Earth's dark shadow at 4:01 a.m. What a way to finish off a year of amazing celestial events.
Be sure to check the NASA Web sites http://spaceweather.com/ and http://antwrp.gsfc.nasa.gov/apod/astropix.html regularly for updates and photographs of these and lots of other exciting celestial events.
Professor Jimmy Westlake teaches astronomy and physics at Colorado Mountain College's Alpine Campus. He is an avid astronomer whose photographs and articles have been published across the world. His "Celestial News" column appears weekly in the Steamboat Today newspaper and his "Cosmic Moment" radio spots can be heard on local radio station KFMU. For a full-color calendar of celestial events in 2010 featuring some of Westlake's best astrophotos, check out "Jimmy's 2010 Cosmic Calendar" at his Web site, http://www.jwestlake.com.