Thursday, October 18, 2012
The Ellensburg sky for the week of 10/20/12
Saturday: The Orionid meteor shower consists of the Earth colliding with pieces of the remains of Halley's Comet's tail. This shower peaks for the next two nights and early mornings. This is not a meteor shower that results in a meteor storm. There will be about 15-20 meteors per hour, many more meteors than are visible on a typical night. The first quarter moon sets at about midnight so it will not be out during most of the prime late night and early morning viewing hours. Meteor showers are named after the constellation from which the meteors appear to originate. These meteors appear to come from a point in Orion, the hunter. This point is about three fists above the southeast horizon at 1 a.m. tonight. You can follow this point throughout the night as it will remain one fist above the prominent reddish star Betelgeuse (pronounced Bet'-el-jews). The Orionid meteors are fast - up to 40 miles per second. If you fall asleep tonight, you can catch the tail end of the shower every night until early November.
Sunday: Mars is a half a fist above due southwest at 7 p.m. If you look very carefully, you should be able to see the bright star Antares right below it. This gives you a great opportunity to see Mars and the anti-Mars. Antares is Ancient Greek for “anti-Mars”.
Monday: “It’s a wonderful day in the neighborhood.” Constellations can be considered neighborhoods in the nighttime sky. But, the stars in those constellations are not necessarily neighbors in real life. For example, the bright stars in the constellation Cassiopeia range from 19 to over 10,000 light years away from Earth. One constellation that consists of real neighbors is Ursa Major. Or, more specifically, the Big Dipper. Five stars in the Big Dipper are all moving in the same direction in space, are about the same age and are all about 80 light years from Earth. “Please won’t you be my neighbor?” Skat, the third brightest star in the constellation Aquarius is a neighbor to these five Big Dipper stars, all of which are about 30 light years from each other. They are thought to have originated in the same nebula about 500 million years ago. Just like human children do, these child stars are slowly moving away from home. Skat is about three fists above due south at 10 p.m. The much brighter Fomalhaut is a fist and a half below Skat. And, it’s not fun being below Skat.
Tuesday: Jupiter is nearly two fists above the east-northeast horizon at 10 p.m.
Wednesday: The Stargate movies and TV shows have access to a portal to other planets. Harry Potter has access to a portal to the Chamber of Secrets. You have access to a Portal to the Universe. This portal is not in Moaning Myrtle’s bathroom but on the web at http://www.portaltotheuniverse.org/. It is a repository of up-to-date astronomy news, blogs, and podcasts. A recent story highlights the discovery of a planet that orbits two stars that, in turn, is orbited by another pair of stars. And if a planet in a 4-star system isn’t amazing enough, this planet was discovered by professional scientists and citizen scientists working together to review data from NASA’s Kepler spacecraft. That’s right. Non-professionals like you and I can comb through data at http://www.planethunters.org/ and possibly help discover a new planet… orbiting two stars… that are orbited by two additional stars… that give away free ice cream every weekend. Okay, I was joking about that last part.
Thursday: Halloween is next week so make sure you load up on peanut clusters, almond clusters, and open star clusters. That last one will be easy (and cheap, actually free) because two of the most prominent open star clusters in the sky are easily visible in the autumn sky. The sideways V-shaped Hyades Cluster is two fists above due east at 10 p.m. Containing over 300 stars; the Hyades cluster is about 150 light years away and 625 million years old. The Pleiades Cluster, a little more than three fists above due east, is larger at over 1000 stars and younger. Compared to our 5 billion year old Sun, the 100 million year age of the Pleiades is infant-like.
Friday: Hit the road Mercury. And don’t you come back no more, no more. For a few weeks, Mercury has been hitting the road and moving away from the Sun in the sky. Today, Mercury is as far away from the Sun as it will get on the evening half of this cycle. This is known as its greatest eastern elongation. Yet, this distance does not translate into good viewing because Mercury will be very low in the sky. Mercury is less than a half a fist above the southwest horizon at 6:00 p.m. Over the next few weeks, Mercury will move toward the Sun in the sky. After it passes in front of the Sun, it will appear in the morning sky by late November.
The positional information in this column about stars and planets is typically accurate for the entire week.