Thursday, May 12, 2016

The Ellensburg WA sky for the week of 5/14/16

Saturday: The New Horizons probe is still sending data from its Pluto pass-by back to Earth. There’s so much information, you need an expert to help you sort it all out. Fortunately, Pluto expert Marc Buie will be talking about New Horizons, Pluto, and beyond at Central Washington University, 4:00 pm today in Lind Hall 215. Lind Hall is on the corner of Chestnut Street and East University Way, D-13 on the CWU campus map found at For more information about the lecture, go to

Sunday: The questions who, what, where, and when can only be asked with a “W”. At 11 p.m., the W-shaped constellation Cassiopeia is about two fists held upright and at arm’s length above due north. The middle star in the W was used as a navigation reference point during the early space missions. The American astronaut Gus Grissom nicknamed the star Navi, his middle name Ivan spelled backwards. After he died in the Apollo 1 fire, the star name was kept as a memorial.

Monday: In an old Saturday Night Live spoof advertisement for a turkey you can pump (, Chris Rock sang, “The first turkey dinner was 1620. The pilgrims had it in the land of plenty.” But he could have just as easily say, “The light left Rasalgethi in 1620. The light now reaches us in the land of plenty.” Rasalgethi is a double star in the constellation Hercules that is almost 400 light years away. Its name is based on the Arabic words meaning, “Head of the kneeler” because some views of Hercules depict him as a warrior kneeling down, perhaps resting after his twelve labors. You’ll find Rasalgethi three and a half fists above due east-southeast horizon at 11 p.m.

Tuesday: Jupiter is four and a half fists above the southwest horizon at 10 p.m.

Wednesday: Give me an “M”. Give me a “3”. What does that spell? “M3.” “Big deal,” you say. It was a big deal to French comet hunter Charles Messier (pronounced Messy A). M3 was the 3rd comet look-alike that Messier catalogued in the late 1700s. M3 is a globular cluster, a cluster of over 100,000 stars that is 32,000 light years away. It is too dim to be seen with the naked eye but is fairly easy find with binoculars. First find Arcturus six fists above the southeast horizon at 11 p.m. Move your binoculars up a little so two stars of nearly identical brightness are in your field of view. When the top star is in the lower left part of your field of view, there should be a fuzzy patch near the center of your field of view. This is M3.

Thursday: At 11 p.m., Mars, Saturn, and the bright star Antares make a small right triangle. Mars, the brightest of the three, is one and a half fist above the southeast horizon. Antares is a little less than a fist below Mars and Saturn is about a fist to the lower left of Mars.

Friday: Earlier this month, astronomers announced that the Kepler Mission verified 1,284 new exoplanets; planets orbiting a star other than our Sun. Read the press release about this discovery at Only nine of the newly discovered planets are in the habitable zone of their host star. This means they orbit their host star at a distance such that there is a good chance for liquid water to exist on their surface. But being in the habitable zone doesn’t mean a planet is habitable. The temperature of the planet depends greatly on its atmosphere. A thick atmosphere would mean a very hot planet like Venus in our own Solar System. Just last year, astronomers discovered the first near-Earth-size planet orbiting a Sun-like star. For more information about this planet, called Kepler-452b, go to

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

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