StarWatch: Moravian College Astronomy

StarWatch for the greater Lehigh Valley

APRIL 2011

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763 APRIL 3, 2011: Dancing with the Stars: Last Tuesday under transparent skies, I had my Moravian College students over to Bill Jacobs’ Farm in Pleasant Valley, PA. Friends, Marcella Gustantino and Joe Zelinski, brought telescopes to help to reduce the viewing lines. None of us had used our “big” scopes since last fall, and we were somewhat like groundhogs becoming conscious from hibernation after a long, cold, winter—a little slow on the uptake, but thank goodness, we didn’t have to cross any busy highway. We would have been all roadkill. Students started arriving about ten minutes before sundown, so I got them familiar with chasing down jet aircraft as they headed into the sunset, their short crimson contrails indicating dry conditions aloft. I pointed out the gray mask of the Earth’s shadow rising in the east. Then Sirius the Dog Star was spotted by keen-eyed, Justin Miranda, no more than 15 minutes after sundown. I was impressed. A few minutes later, more and more luminaries began to battle their way into visibility as a turquoise sky faded to denim. In the west a few degrees above the tree line, Mercury was spotted with binoculars, then with the unaided eye, and then seen through my scope. It was only the second time I had viewed the most elusive of the naked eye worlds through a telescope. Cranky computer drives notwithstanding, that made the evening into a rousing success. For the next hour or so we picked out the Orion Nebula here, the Pleiades there and various other late winter charmers, as we telescopically cruised the ocean of stars. Junior, Kristin Popovice, used my bright green laser to find all of the constellations successfully, as well as down a few planes. I didn’t pack up until nearly 11 p.m., but students had discovered that in the carriage house, Bill and John had prepared a feast fit for any college crowd. Someone reportedly said, “No Taco Bell tonight.” Thanks to all for a great, great evening.

764 APRIL 10, 2011: Lion on the Loose: There’s a cobra on the loose. Nope, I can’t talk about that anymore because Bronx Zoo officials caught the sleuthing snake, slithering in the reptilian house. So fellaheen, take note, there is a lion on the loose, and it’s being chased by the reaper; but the situation isn’t so grim. Both the cobra and the lion have distinctly Egyptian flavors. My wife, Susan, has commented that Nemes headdresses of Egyptian pharaohs have a distinctive cobra’s stylishness including the snake’s head. It was also the cobra that “nipped” the most famous woman pharaoh of all times, Cleopatra, in 30 BC. The lion too, now known as Leo, served as a warning to the Nile farmers along Egypt’s famous river. It was seen in the Egyptian skies as a precursor to the oppressive heat of the summer months, and as a warning to commoners, fellaheen, to be wary of lions coming down from the surrounding dry and dusty hillsides to refresh themselves in the cool waters of Egypt’s lifeblood. Egyptians even had an interesting explanation for why the summers were so hot. Leo’s alpha star, Regulus, lies nearly along the sun’s path through the stars, called the ecliptic. It was the combination of Ra (the sun) and Regulus which caused the stifling conditions of summer. Leo is now visible in the east as darkness falls. If you are outside about 10 p.m., another bright, yellowish star can be observed to be chasing the Lion. That’s Saturn, the harvest god with its ring system now opening and starting to cast shadows on the planet’s disk when telescopically viewed. Spica of Virgo the Virgin will be visible below Saturn. It is one of the brightest blue supergiants of the sky. I cannot forget to mention another stellar sight to the left of Saturn and Spica, Arcturus, the fourth brightest star of the nighttime heavens and the principal luminary of Bootes the Headsmen. See the online map for a 10 p.m. view.

765 APRIL 17, 2011: Training Solar Time: True (apparent) solar time has been used as the basis for time-telling devices since ancient cultures employed it to create calendars for planting and harvesting. The ease of determining the sun’s highest position in the sky always led to a precise measurement of solar noon and consequently, apparent solar time. However, it was only accurate for the exact longitude upon which the measurement was based. A few degrees to the east or west would change the local solar time. As railroading gained popularity in the British Isles in the early 1800’s, east-west train schedules were forced to reflect local times as well as travel times, and it became almost impossible to merge the two into workable timetables. During this same era, ships were becoming faster, necessitating more accurate international maritime shipping schedules. Mariners began running into similar issues when calculating time based upon the moon’s position while on the sea at night. In 1851, Sir George Airy, England’s Astronomer Royal, established the Greenwich Meridian, zero degrees longitude, as the standard for measuring time. It became especially important to railroaders who accurately were able to base their timetables from Greenwich Mean Time instead of apparent solar time. By the 1880’s, over two-thirds of the world’s shippers were using the Greenwich Meridian as their standard. As its popularity grew, it was clear that an official system for time measurement was needed. This was established in October of 1884 when U.S. President Chester A. Arthur convened the International Meridian Conference in Washington to agree upon a time reference. The 41 delegates from 25 nations selected the Greenwich Meridian as the new international Prime Meridian due to its popularity of use. This is the standard that we still use today. This article was written for StarWatch by Rudy Garbely of Moravian College, Bethlehem, PA.

766 APRIL 24, 2011: Oh, Those Meteorite Men: When I entered the huge gymnasium of Rockland Community College about 25 miles NW of New York City, it was the Meteorite Men’s booth that first caught my attention. There sitting on a folding chair munching fries was Steve Arnold of the Science Channel who has traveled the world with Geoff Notkin in search of the extraterrestrial. “They’re too overpriced,” I said to a beautiful assistant working the crowd. She opened one of the cases and handed me a sizeable chunk of a Sikhote-Alin, the biggest fall in recorded history. My fingers raced over this gorgeous baby of beautifully thumbprinted iron and nickel that had struck the Earth in eastern Russia in 1947. She smiled and asked me if I liked it. My head nodded even as I heard the $2000 purchase price. I then moved along to an attractively oriented Gebel Kamil that was bargain priced at only $1500. These space nomads had been discovered in the Egyptian Desert in 2009 and released for purchase last year. But the prize catch was a 180 gram Vaca Muerta full slice from the Atacama Desert in northern Chile. OMG, this beauty had caught my eye on eBay about a month earlier, as another overpriced Meteorite Men trinket, but there it was in its full splendor. Flecks of brightly glittering nickel-iron mixed with rock spoke of an unimaginably violent crash of an iron meteoroid with a stony meteoroid eons ago. It hit Earth well before Neanderthals had roamed Europe and has remained in the Atacama for perhaps as long as 800,000 years, only to be picked up by the MM, sliced and polished, and put on sale for a mere $2700. By this point I must have been foaming at the mouth, and the dark-haired female with her attentive eyes fully expected me to reach for my MasterCard. I thought of my wife, Sue, and our pet rabbits staving for lack of sustenance over my petty greed, and I walked away shaking at the thought of what I had almost done.