Thursday, May 7, 2015
The Ellensburg WA sky for the week of 5/9/15
Saturday: 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 about one fist held upright and at arm’s length above the west-northwest horizon at 9:00 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 mid July.
Sunday: So you think your mother has problems on Mother’s Day because she had you as you as a child? Her mother issues can’t be as bad as Cassiopeia’s issues. First, she was chained to a chair for boasting about her beauty. Second, she has to revolve around the North Star night after night. Third, her daughter Andromeda was nearly killed by a sea monster. Look for poor Cassiopeia about one and a half fists above the north horizon at 10 p.m. Cassiopeia looks like a stretched out “W”.
Monday: Are you thirsty. I’ll wait while you get some water. I will NOT wait while Corvus the crow gets you some water. The Greco-Roman god Apollo made this mistake. He sent Corvus the crow to get some water in the cup known as Crater. Some figs distracted Corvus and he waited for them to ripen so he could eat them. When Corvus got back late, Apollo put Corvus and Crater in the sky with the gently tipping cup just out of the reach of the perpetually thirsty crow. Corvus is a trapezoid-shaped constellation about two fists above due south at 10 p.m. Crater is just to the right of Corvus.
Tuesday: Venus, the brightest point of light in the sky, is more than two fists above the west horizon at 9 p.m.
Wednesday: Jupiter is about four and a half fists above the southwest horizon at 9 p.m.
Thursday: This is a good time of the year to find the Big Dipper. It is nearly straight overhead at 10 p.m. The cup is to the west and the handle is to the east. You can always use the Big Dipper to find some other bright stars. First, follow the curve, or arc, of the Big Dipper down three fists into the southern sky. This is the bright star, Arcturus, the second brightest nighttime star we can see in Ellensburg. Next, continue on a straight line, or spike, another three fists down toward the south horizon to the star Spica. Spica is the tenth brightest nighttime star we can see in Ellensburg. It is known as the Horn Mansion, one of 28 mansions, or constellations, in the Chinese sky. You now know how to use the Big Dipper handle to “arc” to Arcturus and “spike” to Spica.
Friday: Dorothy from the Wizard of Oz clicked her heels and said, “There’s no place like home.” Future Dorothys may be clicking their heels to go to Kepler-186f, the first earth-sized planet orbiting a star in its habitable zone. This means there is a good chance for liquid water to exist on its surface. But it doesn’t mean it 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. For more information about Kepler-186f, go to http://goo.gl/zUZofJ.
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 http://nightsky.jpl.nasa.gov/planner.cfm.