Tuesday, March 1, 2011

The Ellensburg sky for the week of 3/5/11

Saturday: “The crow rises in the southeast” said spy number one. “I’m sorry. I don’t recognize that code” replied spy number two. Spy one exclaimed, “That’s because it’s not a code, you idiot. I’m talking about the constellation Corvus the crow.” This very bad spy movie dialogue is to remind you that Corvus had a very bad life. According to one myth, Corvus brought the god Apollo the news that his girlfriend was seeing someone else. In a classic case of punishing the messenger, Apollo turned the formerly beautifully colored crow black. The box-shaped Corvus is one fist held upright and at arm’s length above the southeast horizon at 10 p.m.

Sunday: Jupiter is about a half a fist to the lower left of the Moon at 7 p.m. Enjoy Jupiter while you can because it is moving toward the Sun in the evening sky. Within a couple of weeks, it will be lost in the glare of the setting Sun.

Monday: 2009 was the International Year of Astronomy. Even though 2009 is long gone, astronomy lives on in the “Hot Topic” of the month. For March, the hot topic is observing at night… and in the day. Technology has expanded the amount of information astronomers can learn from observing the sky. Up until the mid 1900s, we studied the sky using a very narrow portion of the electromagnetic spectrum – visible light waves. It was like studying music by listening only to notes of medium pitch. The invention of the radio telescope opened up a new source of information, long wavelength radiation. It also opened a new time to observe the sky – the day time. Radio waves from outer space are not blocked by the sunlit sky like visible light from outer space is. For the past 50 years, astronomers have started gathering gamma ray, x-ray, ultraviolet, infrared, and microwave radiation. Finally, the entire symphony of wavelengths rather than just a few notes. But technology has also negatively impacted our view of the nighttime sky through light pollution. The dim light of a distant galaxy is facing more and more competition from businesses that use inefficient lighting that lights the sky as much as it lights the ground. Many communities, including Ellensburg, have passed or are working on ordinances to reduce this costly and sky-robbing stray lighting. Go to http://astronomy2009.nasa.gov/topics_mar.htm for more information about the March “Hot Topic”.

Tuesday: Some people dream of moving into a high-rise. Craters on Mars dream of being photographed by HiRISE, the High-Resolution Imaging Science Experiment, the largest telescope ever flown to another planet. It can see details down to one foot across. But, it didn't need much resolution on January 10 when it snapped a picture of twin craters, each about one mile across, connected on their side. The object that made the craters probably broke into two nearly equal sized objects in the thin Martian atmosphere and hit the ground at nearly the same time. For more information, go to http://www.skyandtelescope.com/news/117192413.html.

Wednesday: In this busy world, it is important to know what time it is. We have many devises that give us the time. Our phone, a computer, a watch. But who has time to build a phone, computer or evan a watch. Not you. But everyone has enough time to build a simple Sun Clock. All you need is a pencil, a compass and a print out of the clock template. Go to http://www.exploratorium.edu/science_explorer/sunclock.html for more information.

Thursday: Seven sisters are hanging out with the Moon tonight. The open star cluster known as the Pleiades, or the Seven Sisters, is less than a half a fist above the Moon at 7 p.m. Since the Moon is so much brighter than the stars in the cluster, it will be very difficult to see the sisters with the naked eye. Instead, aim your binoculars so the Moon is just below your field of view. The Pleiades will be near or below the middle of your field of view.

Friday: Saturn is three fists above the southeast horizon at 11 p.m. The bright star Spica is below it. Note the difference in the colors of the two objects. Saturn is a yellowish-orange color because of the material in its atmosphere. Spica is a whiteish-blue color because it is glowing like an extra hot light bulb filament. Star color os related to the temperature of the star. Red stars have smaller energy level transitions so they are cool. Blue and whiteish-blue stars have larger energy level transitions so they are hot.

Wait a minute. We got all the way to the end of the week with no Moon phase summary? How can that be? There are 29.5 days between the same Moon phase in two different cycles. That means about 7.5 days between the phases new, first quarter, full and last quarter. Since a week is seven days, there are some weeks in which none of the main phases occur. This week, the Moon was always in the waxing crescent phase.

The positional information in this column about stars and planets is typically accurate for the entire week.

No comments: