StarWatch: Moravian College Astronomy

FEBRUARY 2007

FEBRUARY STAR MAP | STARWATCH INDEX | MOON PHASE CALENDAR

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[Venus and Mercury]

This image of Venus and Mercury (fainter and nearer to the trees) taken on February 3rd was aided by thin clouds which diffused their light making them appear brighter. Mercury was easily visible to the unaided eye in this photograph taken by Gary A. Becker from Coopersburg, PA.

546 FEBRUARY 4, 2007: Meteor Crater: Last week, I wrote about meteorite craters on the moon. Space prevented me from saying that the best-preserved meteorite crater on Earth, misnamed Meteor Crater, lies not quite 20 miles west of Winslow, Arizona along I-40 at exit 233. If you have a desire to see the Grand Canyon this summer, then may I suggest Flagstaff, AZ as your staging area because you will be just 2-1/2 hours south of the GC and just an hour’s drive west of Meteor Crater. In addition, you’ll be able to hike or drive in the rich volcanic fields of Sunset Crater Nat. Monument or see Ancestral Puebloan homes in Wupatki and Walnut Canyon, all only a half-hour’s drive from Flagstaff. And then there are the public viewing nights at the Lowell Observatory on Mars Hill. Plan to stay in Flagstaff for at least a week. Overlooked by tourists scrambling for a glimpse of the over trodden Grand Canyon, Meteor Crater is indeed special. The 4,100-foot diameter basin was carved by a 100-yard iron-nickel meteorite that slammed into the northern Arizona high plateau nearly 50,000 years ago. Its crater walls still rise as high as 200 feet above the local terrain and can be glimpsed from I-40 six miles distant. Almost every time I am there, my car magically follows the exit ramp, and I find myself driving the narrow macadam access road to a small pullout just to marvel at how something so small could have created something so huge. Last year, I drove all the way to the parking lot, maybe for the tenth time, and plucked down my 15 bucks to revisit its jutting limestone rim and gaze with awe into its deep 550-foot pit. The experience, I think, is similar to the Grand Canyon. I simply cannot fathom its grandeur in my mind, and no picture can do it justice. So blinded by mental inertia, I am forced to return again and again to reconfirm its immenseness.

547 FEBRUARY 11, 2007: Orion's Sword: Orion the Hunter, one of the most famous star patterns of the night sky, is center stage in the SSE as darkness descends. The constellation remains well-positioned for several more hours during the early evening with its three belt stars, equally bright and equally distant (top to bottom) Mintaka, Alnilam, and Alnitak. They are universally known by even the most casual observer. Beneath Orion’s belt is the more elusive sword, which appears to the unaided eye as three fainter stars, but when viewed through binoculars or small telescopes, resolve themselves into clusters and nebulae. By far the most famous is the Orion Nebula (M42), 30 light years in diameter and 1,500 light years distant. It is a birthing place for stars. Its Trapezium cluster of four stars is visible through small telescopes, but Theta¹ C Orionis, containing 40 times more hydrogen than our sun, is a standout even in binoculars. Its brightness equals 210,000 suns making Theta¹ C one of the most luminous stars visible. It will probably supernova in about one million years. Just above the Orion Nebula is M43, structurally tied to M42, but separated by a dark lane of dust. It possesses its own small cluster of stars. Target this area with a telescope. Above M43 lies The Running Man, NGC 1977, a small cluster of related stars that forms the top of Orion’s sword to the unaided eye. Through binoculars three tightly packed stars can be viewed with an additional luminary above and to the right. Photography reveals a beautiful blue reflection nebula associated with the dust through which the brightest star, 42 Orionis, is shining. Below the sword lies Iota Orionis, a naked eye star, which is associated with a very faint nebulosity, NGC 1980, not easily seen even through large telescopes. All of this and more lies easily within one binocular field of view.

548 FEBRUARY 18, 2007: Umbra to Court Moon: If during the past two weeks you did not get the chance to see Mercury and Venus after sundown, you can view images of this event by going to the URL below and clicking on “this week’s StarWatch.” Scroll down from the top of the page. Watch as the moon waxes or grows this week and the dusky ashen light which appears to illuminate the entire lunar disk diminishes. The ashen light, or earthshine, is Earth’s reflected sunlight reflected back to us from the moon. From the moon, the Earth is diminishing in brightness while on Earth the moon’s brightness is waxing making the earthshine more difficult to detect with each passing day. While you are watching the moon wax during the following week consider that it will be moving towards a rendezvous with Earth’s shadow on Saturday, March 3rd. The East Coast will be treated to a total lunar eclipse, the first one to be seen since October 27, 2004. This eclipse, however, will require a good eastern horizon without obstructions, and very transparent skies to take full advantage of all of the varied lighting effects that could be discernible. The moon will rise invisibly at 5:50 p.m., deep within the shadow or umbra of the Earth. The sun will set five minutes later, and sometime during the next hour, as sky conditions grow darker, the eclipsed moon should hopefully begin to reveal itself. The clearer the sky, the earlier observers should be able to spot the moon. The brightness of the eclipse will also play a major factor in how early the moon will become visible. A brighter eclipse will be seen earlier. At the very least, even if sky conditions are hazy, we should be able to witness the moon emerge from Earth’s shadow starting at 6:58 p.m. The ASD Planetarium’s StarWatch team will be observing this event from the Quakertown Airport. Read ahead on the web.

549 FEBRUARY 25, 2007: See Lunar Eclipse at Quakertown Airport
This coming Saturday members of the ASD Planetarium’s StarWatch Team will have their telescopes set up at Quakertown Airport, 2425 Milford Square Pike, 215-538-3055 to view the first total lunar eclipse since October 27, 2004. The public is invited to view this event and also to bring telescopes, spotting scopes, and binoculars to join in the fun. Total lunar eclipses take place when the full moon crosses the plane of the Earth’s orbit and passes through the Earth’s shadow. This eclipse, however, is different from most events of its type. The full moon will rise, completely eclipsed, about five minutes before sundown. Moonrise will, therefore, be invisible. As sky conditions darken over the next hour, the eclipsed moon should become discernible, especially just before it begins to emerge from Earth’s shadow at 6:58 p.m. During the next 74 minutes as the moon slowly emerges from Earth’s umbra, it will brighten the landscape as well as the sky. Besides watching the eclipse, participants will also be able to observe the planet Saturn and other sky objects, like the Orion Nebula and the Pleiades. Plan to arrive at the Quakertown Airport no later than 6 p.m. if a spectator/5 p.m. if you plan to set up a telescope. Layer your clothing, taking extra precautions to make sure that head, hands, and feet are well-protected. From the Lehigh Valley, travel Rt. 309 south until it intersects Rt. 663 at Trainer’s Corner Shopping Center in Quakertown. Turn right onto Rt. 663 and proceed past a traffic light and a BP Mini Mart. One block past the mini mart, turn left onto Milford Square Pike. A left near the end of a small industrial park brings you to the airport. This is a clear weather event. A go/no go message will be posted at the URL below by 3 p.m., March 3rd. Online maps are also available.

Quakertown Airport will be the observing site for the March 3rd total lunar eclipse. This picture looks eastward into Quakertown, PA with the small industrial park mentioned in the article to the left of the image. Photography by Gary A. Becker...

Use this bird's eye view of the Quakertown Airport in addition to the article above to help find the observing location for the March 3, 2007 total lunar eclipse. Google Maps...