Thursday, April 17, 2014
The Ellensburg sky for the week of 4/19/14
Saturday: The first day of spring was March 20. The most recent full moon was last week. That means tomorrow is Easter. The standard way to determine the date of Easter for Western Christian churches is that it is the first Sunday after the full moon that occurs on or after the vernal equinox, also known as the first day of spring. Of course, the other standard way is to look for the date of church services celebrating the resurrection of Jesus. There is no Bible story of an “Easter star”. If there were, Spica would be a pretty good choice. The name Spica comes from the Latin “spica virginis” which means “Virgo’s ear of grain”. Spica represents life-giving sustenance rising after a long winter just like the risen Jesus represents life-giving redemption to Christians. Spica is one fist held upright and at arm’s length above the east-southeast horizon at 8:30 p.m. For an algorithm on how to calculate the exact date of Easter for any year, go to http://goo.gl/gFnepP.
Sunday: This week is International Dark Sky Week, a week to celebrate the night sky and think about how we can reduce light pollution. Because of an overabundance of inefficient outdoor lighting, the thick band of the Milky Way is not visible from even small cities such as Ellensburg. For more information about what you can do and to learn about the aesthetic, health, and environmental effects of light pollution, go to http://goo.gl/w6Hi7.
Monday: Mars is three and a half fists above the southeast horizon at 10 p.m.
Tuesday: Remember the old saying: April showers bring… meteors. The Lyrid meteor shower peaks tonight. The meteors appear to come from a point to the right of the bright bluish star Vega in the constellation Lyra the lyre. This point is about three fists above the east-northeast horizon at midnight tonight and close to straight overhead near dawn. The best time to look is just before dawn since that is when the radiant, or point from which the meteors appear to come, is high in the sky. This year, the Moon is in the last quarter phase meaning it will be bright and be out for most of the prime viewing time. Typically, this is one of the least interesting major meteor showers of the year. However, it is also one of the most unpredictable. As recently as 1982, there were 90 meteors visible during a single hour. In addition, the Lyrid meteor shower has historical interest because it was one of the first ones observed. Chinese records say “stars fell like rain” in the shower of 687 B.C. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the Earth and burn up in the atmosphere.
Wednesday: As the weather warms up, people start thinking about swimming in a nice cool body of water. Recently, astronomers have discovered evidence an ocean about 20 miles beneath the surface of Saturn’s moon Enceledas. NASA’s Cassini probe measured variations in how the moon’s gravity pulled on the orbiting spacecraft. These variations can be explained by a large amount of liquid water under one section of the ice because liquid water is denser than an equal volume of ice. While you need a very large telescope to see Enceledas, Saturn is visible to the naked eye tonight, one fist above the southeast horizon.
Thursday: Jupiter is four and a half fists above the west horizon at 9 p.m.
Friday: Venus is a half a fist below the moon, low in the eastern sky at 5:30 a.m. That’s right, 5:30 a.m. The Sun rises early now. You can’t waste the day sleeping.
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 https://nightsky.jpl.nasa.gov/planner.cfm.