Thursday, March 24, 2011

The Ellensburg sky for the week of 3/26/11

Saturday: Say good bye to Jupiter. It is just above the west horizon at 7:45 p.m. You may need binoculars to find it hiding in the glare of the setting Sun. Over the next few weeks, Jupiter will move behind the Sun and show up in the early morning sky.

Sunday: Venus, the brightest planet, is a half a fist held upright and at arm's length above the southeast horizon at 6:15 a.m. Neptune, the dimmest planet, is just to the upper right of Venus. But, you'll need binoculars to find it. When Venus is at the center of your field of view, Neptune will be the dim point of light at the 2 o'clock position.

Monday: Mercury and its human-made moon are one fist above the west horizon at 8 p.m. The "moon", also known as MESSENGER or MErcury Surface, Space ENvironment, GEochemistry, and Ranging, orbits Mercury once every 12 hours, getting as close as 124 miles from the surface of the planet. For comparison, the International Space Station orbits about 200 miles above the Earth's surface. For more information about the MESSENGER mission, go to http://messenger.jhuapl.edu/.

Tuesday: Leo the lion prowls the sky in the late winter and early spring. Regulus, the brightest star in the constellation, is five fists above the southeast horizon at 9 p.m.

Wednesday: So far this week, I have written about Mercury, Venus, Jupiter, and Neptune. Do you even care about these planets or does another planet really catch your fancy? If you’d like to learn what certain people’s favorite planet is, go to http://www.pbs.org/wgbh/nova/pluto/favorite.html and click on “Launch Interactive”. The public TV special called “The Pluto Files” has set up a website in which astronomers give a 30-second pitch for why a certain planet might be their favorite. After listening to the pitch, you may vote for your favorite planet. Of course, you may also do what most people do for political elections: vote for the candidate with the best name or the one with the most interesting campaign slogan. So whether you carefully consider each planet's merits or simply “Pick Uranus”, go to “The Pluto Files” and vote. Saturn will be holding a campaign rally tonight at 11 p.m., two fists above the southeast horizon.

Thursday: Venus is about a half a fist to the lower right of the Moon in the eastern sky at 6 a.m.

Friday: After a long journey through space, there is nothing will quench your thirst better than a few drops of refreshing Mars water. Wait! Is this an April Fool’s Day joke? No. Last year, after analyzing photos taken by the Mars Phoenix Lander, a group of astronomers discovered what they interpreted as drops of very salty liquid water on one of the Lander’s legs. But we are not going to travel 18 months to Mars just to lick a few drops of water off a metal leg. We want waterfront property if we are going all that way. The high resolution camera aboard the Mars Reconnaissance Orbiter has taken images of dark rivulets form, grow, and fade in the Martian southern hemisphere. Even though Mars is very cold, this liquid could contain enough salt to lower its freezing point by more than 100 degrees Fahrenheit. Mars and that refreshing water rises due east just before the Sun. For more information about liquid water on Mars, go to http://www.skyandtelescope.com/news/117806243.html.

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

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