StarWatch: Moravian College Astronomy

DECEMBER 2016

DECEMBER STAR MAP | MOON PHASE CALENDAR | STARWATCH INDEX | NIGHT SKY NOTEBOOK

Print Large Sky Charts For 9 p.m. EST: NORTH | EAST | SOUTH | WEST | ZENITH

Current Solar X-rays:

Current Geomagnetic Field:

lunar phases

1059 DECEMBER 4, 2016: Waxing Moon to Hide Aldebaran: As December’s chills engulf us and star watching creates the added burden of dressing in warmer clothing, you may want to consider a quick pop out-of-doors to view the moon. This is a daily occurrence for me just to see how conditions are progressing even when it’s cloudy. Luna is waxing this week, growing and brightening in moon phase terminology. Looking SW on Sunday, Dec. 4 around 6 p.m., will reveal a really bright star to the lower right of Luna’s location and a fainter luminary just to the moon’s left. You’ll be seeing brilliant Venus and Mars respectively, in addition to a 26 percent lit waxing crescent (horned) moon. If conditions are very clear, you may be able to view earthshine with the unaided eye, illuminating the unlit portions of the moon. Sunlight reflects off the Earth which is in the opposite phase of the moon; in this case, a bright waning gibbous, and then is reflected back to us causing this ashen light to be seen on the parts of the moon which have yet to be directly illuminated by the sun. The moon pulls away from Mars on subsequent evenings reaching first quarter, half on—half off, light to the right, on December 7 just after 9 a.m. on the East Coast. By the time we see Luna that evening, both “sides” of the moon, the limb which is against the sky and the terminator where night is changing into day, will be rounded outward—convex. The moon will be in a waxing gibbous phase, the word coming from the Latin “gibbus” to bulge or more precisely a protuberance or a lump. Keep watching the moon over the next five days as it approaches the bright alpha star of Taurus the bull, Aldebaran. On the evening of Dec. 12, the nearly full moon occults Aldebaran on its unlit side just after 11 p.m., EST. Watch through binoculars as the moon “inches” towards this old, orangey, giant star during the early evening. The actual disappearance will require a telescope to view, but it will be interesting to see how close to the moon Aldebaran will continue to be seen through binoculars. Much success!

1060 DECEMBER 11, 2016: Skies Unlimited: Telescopes and Christmas—they go together like mistletoe and kisses, but most people buying a scope for under the tree will make the wrong decisions. All telescopes are compromises in one way or another, but all experts agree that telescopes are not built strictly for magnification. If a manufacturer hypes the power that a telescope can attain as the chief reason for purchasing the scope, stay away from that product. The most important attribute of a telescope is its ability to gather more light than the human eye—more light to see deeper into space. In addition, a good telescope will bring the light collected by a mirror or a lens to a crisp, contrasty focus in a comfortable manner. The eye, acting as the receptor of the gathered photons, essentially becomes as large as the surface of the light-gathering area of the telescope. Department store scopes like those sold at K-Mart or Wal-Mart are, simply put, overpriced and poor performers attached to unstable mounting systems that quickly drive potential enthusiasts to other hobby interests. Manufacturers like Orion, Celestron, Explore Scientific, and Meade produce good instrumentation in the $300 to $600 bracket, and all have good websites hyping their products. My suggestion, if you’re thinking about a scope for Christmas, is to visit a retail store that exclusively sells telescopes and talk to a knowledgeable individual who knows the market and can make appropriate suggestions. Places like these are few and far between, but locally serving the Greater Philadelphia and Lehigh Valley regions is Skies Unlimited (skiesunlimited.com) in Pottstown, PA, at 52 Glocker Way, 19465 (888-947-2673). I was just there this past Friday, Dec. 9, and they had “tons” of used and new equipment on their showroom floor, real telescopes, and many at affordable prices. Talk to Bob, Ted, or Dave for a no pressure introduction to the telescope market. Skies has treated me and Moravian College very fairly and will do the same for you. Skies unlimited to all!

1061 DECEMBER 18, 2016: Anticipating Summer Starts This Week: Completing the transition from cool to cold, Old Man Winter has already shown us his more vicious side. Now it’s “batten down the hatches” until the first signs of spring start to blossom, usually by mid to late February, when on a sunny, windless, day you can feel the trapped radiant heat that your car has been able to capture, allowing you to feel warm upon entering. However, the mechanism towards balmier times will begin this week after the winter solstice on December 21 at 5:44 a.m. EST. The word “solstice” comes from the Latin for “sun still,” when the sun reaches its lowest noontime position in the sky for the year. Thereafter, Sol begins to move upward, very, very slowly at first, then gains speed during February, maxing its northerly climbing rate on the vernal equinox, Monday, March 20, 2017 at 6:29 a.m. EDT. Still, everyone knows the cold weather dosen’t cease when the sun begins its upward trek. The Northern Hemisphere is still giving up more energy than it is receiving from the sun, so daily average temperatures will continue to be lower for about another month, bottoming in late January about a month after the winter solstice. All of this cold weather results from Earth’s axial tilt. We “lean back” during the winter months causing the sun to be lower in the sky and its warming energy to be dissipated, similar to watching the size of a flashlight beam broaden on the ground as its angle is changed from the vertical to the horizontal. Another winter fact about the sun is that it rises south of east and sets south of west, making its daily trek across the sky shorter and Sol’s time above the horizon less. The remarkable part about all of this winter talk is that Earth reaches its closest position to the sun, perihelion, on January 4, 2017 at noon EST. The seasons have nothing to do with Earth’s orbital distance from the sun. Our closest position to Sol means that Earth is traveling fastest in its orbit around the sun. This translates into a shorter duration of time between fall and spring, giving us just a little more time in the warmer sun. Happy Winter Solstice to all! Can’t wait for summer…

1062a DECEMBER 25, 2016: Godspeed, John Glenn: The death of John Glenn on December 8 marked the passing of yet another person who was greatly admired by the public and me especially. He was a role model who exemplified all that was good about humanity, and at 95, the last surviving member of the famed Mercury 7 crew, the first American astronauts to fly into space. In a July 30, 2015 interview with Glenn conducted by Paul Levinson (Touching the Face of the Cosmos along with Michael Waltemathe, Connected Editions, New York, 2016), Glenn spoke about religion and space travel among other topics. “My going into space strengthened my religion—to see everything, what we are part of, part of creation, to see whole nations and oceans and everything at a single glance, that just strengthened my belief. That’s not where it came from, it just strengthened the beliefs I already had.” About taking our religion with us as humanity ventures into space… “…I think we take our religious faith with us wherever we go and the same is true going into space. And it will be true whether we go to Mars, or Pluto, or wherever we may wind up eventually going. …Once we get there our religious faith and belief or beliefs will not be altered, except maybe we’ll appreciate the enormity of it all, more than we ever did before.” About the conflict between science and religion… “They are complementary. I don’t see them as competitive at all. I think they’re complimentary. The more you know about things, the more you appreciate, the more it strengthens our religious beliefs.” Did going into space change you as far as what you thought about the universe and humanity’s place in it? “No, not really. I think some people… say there I was in space and saw the face of God or something like that. That’s not the way it was at all with me.” About seeing the universe as a spiritual experience… “It’s an experience, yes, that backs up my religious faith. It doesn’t replace, didn’t start it, didn’t stop it, just strengthens it.” Godspeed, John Glenn.

1062b DECEMBER 25, 2016: Moravian Can Help Take Back the Night!: When I was eight years old, my interest in astronomy was fueled by a single event. Crossing my front yard on my way to a Cub Scout meeting, I casually glanced skyward and caught a bright meteor gliding amongst the stars. My next memory was a scared, out of breath kid banging on the front door of the meeting place. My mother at 91 still lives in that same home, but the story could never repeat itself. Over the intervening 60 years, a blight of light has crept outward from our cities, making the nighttime sky nearly inaccessible to urban dwellers. The shooting star that I saw in 1958 would be invisible to a 21st century child repeating the same scenario. Cities changed from incandescent to mercury and high pressure sodium vapor lighting, and now, because of even greater efficiency and a more natural illumination, LED lamps. From Moravian College’s Sky Deck, the highest accessible location to students on campus, a good night means that 75 stars are visible to the unaided eye. Moravian’s light pollution footprint is substantial, even though the campus has benefited greatly from LED technology. Still, more than half of the electricity that lights Main Campus is directed skyward where it helps to disrupt the nighttime ecology of our trees and plants and also hides the stars. Buildings like PPHAC have decorative ground lighting splashed upon their walls. The new soccer field lights are kept burning regardless of field usage. Yet I firmly believe that Moravian is still ahead of the game, and I’d like to propose three additional suggestions which would save the College even more money and improve lighting efficiency. Please turn off the decorative ground lighting of buildings such as PPHAC. Attach an internal sheet of tinfoil or use reflective paint on each of the four skyward pointing glass panes of main campus lamp posts to focus more light downward and augment ground illumination. Finally, continue to retrofit old lamps with new LED technology. We can do it right and help take back the night. Ad Astra!

Moravian College’s light pollution footprint is substantial, especially when money is spent for the ground illumination of buildings like PPHAC (first image). Campus lamp posts should only light up the ground and not buildings. They should not shine into vegetation and trees where ecological niches are being disrupted. Let us promote green, by becoming even greener, and save more green in the process. Let’s help take back the night! Images from the Sky Deck by Gary A. Becker...