Thursday, February 12, 2015
The Ellensburg WA sky for the week of 2/14/15
Saturday: According to Greek mythology, the beautiful princess Andromeda was chained to a rock next to the ocean. Cetus the sea monster was about to devour her in order to punish her family. It seemed that all was lost. But, along came the great warrior Perseus, fresh off his defeat of the evil Gorgon, Medusa. The only similarity between Andromeda and Medusa was that Andromeda caused people to stand still and stare at her beauty while Medusa turned people to stone because of her ugliness. (And, you thought you looked bad in the morning.) Even though Perseus’ standing as the son of King Zeus and the slayer of Medusa was probably enough to win Andromeda under normal circumstances, Andromeda’s impending death-by-sea-monster was not a normal circumstance. So, Perseus drove his sword into the sea monsters neck and killed it. In a little known addendum to the story, Perseus carved “Percy (heart symbol) Andi” in the rock, thus originating the use of the heart symbol as a substitute for the word “love”.
You can find these lovers in the sky this Valentine’s Day. Just remember it is rude to stare – and you never know when you might turn to stone. First, find the Great Square of Pegasus at 7 p.m. between one and a half and three and a half fists held upright and at arm’s length above the west horizon. The lowest star in Andromeda is the top star in the square. This represents Andromeda’s head. Perseus is at her feet, nearly straight overhead. Mirphak, the brightest star in Perseus, is about eight fists above the west horizon. Perseus’ body is represented by the line of stars to the left and right of Mirphak.
Sunday: Venus and Mars are neighbors near the western horizon this week. At 6:30 this evening, Venus is a little more than a fist above the west-southwest horizon. Mars is less than a half a fist to its upper left. As the days go by, Venus will slowly move up from the horizon and Mars will move down to the horizon. By early next week, they will nearly bump into each other in the sky. Of course, they will really be millions of miles apart.
Monday: The first human-made probe to visit a dwarf planet will reach its destination early next month. But it has already started sending back pictures. The Dawn mission will arrive at Ceres on March 6. Ceres is the largest object in the main asteroid belt between Mars and Jupiter. It was actually classified as a planet for a few years after it was discovered in 1801. As with any good science mission, Dawn has answered a few questions and raised many more. Since you can’t see Ceres in the night sky – it is now out during the daytime – do to http://goo.gl/hdCRIx for a two second movie of Ceres rotation.
Tuesday: Jupiter is five and a half fists above the southeast horizon at 10 p.m.
Wednesday: “Happy Birthday to you. Happy Birthday to you. Happy Birthday dear Pluto. Happy Birthday to you.” On this day in 1930, Clyde Tombaugh discovered Pluto, at that time classified as the ninth planet. However, as astronomers started discovering a lot of similar objects in that part of the solar system, they realized that had a classification crisis on their hands. Should everything in this region of the solar system be named a planet? Eventually the International Astronomical Union (IAU) reclassified Pluto and all future Pluto-like objects as dwarf planets. According to his wife, if Mr. Tombaugh were alive today, he maybe disappointed at the reclassification but he’d accept it because, as a scientist, he’d recognize the implications the new naming scheme would have on future discoveries. Besides, noted astronomer Hal Levison, while Tombaugh didn’t discover the ninth planet, he discovered the Kuiper Belt and that’s a whole lot more interesting. The New Horizons probe will reach Pluto July 14, 2015. See http://pluto.jhuapl.edu/ for more information.
Thursday: Saturn is two and a half fists above due south at 6:15 a.m.
Friday: Along with Pluto, Tombaugh discovered numerous asteroids, variable stars, and star clusters. Up until recently, the responsibility of naming all of these objects would have belonged to the International Astronomical Union. But in 2013, the IAU revised their naming rules to let individuals suggest names for certain celestial objects. They are running a contest to name certain objects. For more information, go to http://www.nameexoworlds.org/.
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.