Friday, December 8, 2017
The Ellensburg WA sky for the week of 12/9/17
Saturday: Warrant, the American glam metal band (as labeled by Wikipedia) was singing about carbon stars in its 1991 hit “I Saw Red”. The lyrics for the astronomy version are “Then I saw red, when I looked up in the sky, I saw red, Orion’s bright star it was by.” R Leporis, also known as Hind’s Crimson Star, is one of the reddest stars in the sky. It is a star near the end of its life that has burned its helium nuclei into carbon. Convective currents, like those in a pot of boiling water, bring this carbon to the surface. There it forms a layer of soot that scatters away the light from the blue end of the visible spectrum leaving the light from the red end of the spectrum to reach our eyes. For more information about Hind’s Crimson Star and a list of other deep red stars, go to http://goo.gl/EnhRe4. Hind’s Crimson star is one fist to the lower right of Rigel, the brightest star in Orion. You’ll need binoculars or a small telescope to see it Hind’s Crimson star. But you can easily spot Rigel two fists held upright and at arm’s length above the southeast horizon at 9 p.m.
Sunday: Saturn will be obscured by the light of the Sun for a few weeks before peeking up in the morning sky in mid-January.
Monday: Just before Christmas, you look for junk to clean out of your closets so you can re-gift it. I mean, so you can throw it out or recycle it. NASA’s Meter Class Autonomous Telescope on Ascension Island is a key tool in a program tracking about 22,000 pieces space junk. Some of this junk is dangerous. The International Space Station occasionally performs debris avoidance maneuvers to keep is panels and sensitive instrument safe. For more information about the project, go to http://goo.gl/Kxgihd.
Tuesday: The bright star Capella is nearly straight overhead at midnight tonight.
Wednesday: The Geminid meteor shower peaks tonight. Meteor showers are named after the constellation from which the meteors appear to originate. These meteors appear to come from a point in Gemini the twins. This point is about three fists above the east-northeast horizon at 9 p.m. tonight. You can follow this point throughout the night, as it will remain near the bright star Castor, the right hand star of the “twin” stars Pollux and Castor. This shower is typically one of the best ones of the year producing bright, medium speed meteors with up to 120 meteors per hour under ideal conditions near the peak. This year IS near ideal because the Moon is close to new so it will be below the horizon for most of the night.
Most meteor showers occur when the Earth passes through the orbital trail of a comet. The broken off comet fragments collide with the Earth and burn up in the atmosphere. Astronomers had searched for a comet source for this shower since 1862 when the shower was first observed. Finally, in 1983, astronomers discovered the object that created the fragments that cause the meteor shower. To their surprise, it was a dark, rock that looked like an asteroid, not a shiny icy comet. Astronomers named this object Asteroid 3200 Phaethon. As an added bonus this year, this asteroid is visible through a small telescope. If you are up for the challenge of finding 3200 Phaethon, go to http://www.skyandtelescope.com/observing/3200-phaethon/. For more information about the Geminid shower, go to http://www.skyandtelescope.com/observing/geminid-shower-2017/. Now that’s a self-explanatory URL!
Thursday: Jupiter is less than a half a fist to the lower right of the Moon in the southeastern sky at 7 a.m. Mars is a little more than a fist to the upper right of the Moon.
Friday: Columbia the dove, representing the bird Noah sent out to look for dry land as the floodwaters receded, is perched just above the ridge south of Ellensburg. Its brightest star Phact is about one fist above the south horizon at midnight.
The positional information in this column about stars and planets is typically accurate for the entire week. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.