Wednesday, February 4, 2015

The Ellensburg WA sky for the week of 2/7/15

Saturday: Jupiter is at opposition tonight. No, that doesn’t mean that Jupiter refuses to eat his vegetables. (Please eat your vegetables, children.) Opposition means that Jupiter is on the opposite side of the Earth as the Sun. An object is in opposition when it is due south 12 hours after the Sun. When an object is in opposition, it is at its highest point in the sky during the darkest time of the night. A planet in opposition shines brighter and appears larger in a telescope than any other night. And since Jupiter is also the largest planet, it reflects a lot of sunlight. Jupiter is about five fists held upright and at arm’s length above the south-southeast horizon at 11 p.m.

Sunday: The universe contains everything from gigantic galaxy clusters to tiny parts of atoms so it is difficult to visualize all of it on the same scale. Cary and Michael Huang have created an interactive scale model of the universe which allows you to “slide” from a vantage point outside the known universe down to the smallest things ever theorized. To take this trip, go to

Monday: You think wintertime weather is bad in Ellensburg. Astronomers have discovered storms and earth-sized clouds on a brown dwarf. These are cool, small stars that are not massive enough to fuse hydrogen atoms and fuse hydrogen. In fact, they are more similar to gas giant planets such as Jupiter that to the Sun. In this context, the discovery of storms similar to the giant Red Spot on Jupiter makes sense. For more information, go to

Tuesday: Winter is a good time to see the thick band of the Milky Way galaxy. It arches high in the high in the early evening starting in the southeast by Sirius, the brightest star in the night sky. Climbing from Sirius through the "horns" of Taurus high overhead, it drops down toward M-shaped Cassiopeia in the north and the tail of Cygnus, the swan, in the northwest.

Wednesday: Saturn is about two and a half fists above the south horizon at 6:30 a.m.

Thursday: It is often said that Earth is a water world because about 70% of the Earth’s surface is covered by water. What would it look like if all that water on the surface were gathered up into a ball? That “ball” would be about 700 km in diameter, less than half the diameter of the Moon. The Astronomy Picture of the day shows us right here

Friday: This President’s Day weekend, let’s remember Abraham Lincoln: 16th president, country lawyer, man on the penny, vampire hunter, and astronomer. Vampire hunter? No. Astronomer? Well, maybe not an astronomer, but someone who used observational evidence from the sky to solve a problem. In 1858, Lincoln defended Duff Armstrong, a family friend who was accused of murder. The prosecution thought they had a strong case because their primary witnesses claimed to have observed the killing by the light of the nearly full moon. Let’s listen in on the trial courtesy of the 1939 film, Young Mr. Lincoln.
Lincoln: How’d you see so well?
Witness: I told you it was Moon bright, Mr. Lincoln.
Lincoln: Moon bright.
Witness: Yes.
(Dramatic pause as Lincoln reaches for something)
Lincoln: Look at this. Go on, look at it. It’s the Farmer’s Almanack (sic). You see what it says about the Moon. That the Moon… set at 10:21, 40 minutes before the killing took place. So you see it couldn’t have been Moon bright, could it?
Lincoln used the known information about Moon rising and setting times for August 29, 1858 as evidence in a trial. This is one of the earliest uses of forensic astronomy. You may confirm Lincoln’s findings on the Moon set time by going to, the US Naval Observatory website, and filling out Form A. For more information about Lincoln’s “almanac trial”, 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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