Thursday, December 19, 2013
The Ellensburg sky for the week of 12/21/13
Saturday: At 9:11 a.m., the Sun reaches its lowest point in the sky with respect to the background stars. This point is called the Winter Solstice. During the day that the Sun reaches this point, your noontime shadow is longer than any other day of the year. Also, the Sun spends less time in the sky on the day of the Winter Solstice than any other day making this the shortest day of the year. Even though it is the shortest day of the year, it is not the day with the latest sunrise or the earliest sunset. The latest sunrise is during the first week in January and the earliest sunset is during the second week in December. The Sun is at its southernmost point with respect to the background stars on the day of the winter solstice. This means the Sun spends the least amount of time above the horizon on that day. But, the Sun rise and set time depends on more than its apparent vertical motion. It also depends on where the Sun is on the analemma, that skinny figure-8 you see on globes and world maps. During the second week in December, the Sun is not quite to the bottom of the analemma. But, it is on the first part of the analemma to go below the horizon. During the first week in January, it is on the last part of the analemma to rise above the horizon. For more information on this, go to http://goo.gl/KpbkTf.
Sunday: I know you’re staying up late to train yourself to wait up for Santa. So look out a south-facing window at 1 a.m. and see Sirius, the brightest star in the nighttime sky, as high as it ever gets in the sky. It is two and a half fists held upright and at arm’s length above due south.
Monday: Are you gaining a few pounds from too many Christmas cookies? The planet Venus isn’t. It has a thin crescent shape this month. Not because of willpower. No, Venus wants to chow down. Venus is a thin crescent because most of the illuminated side of Venus us facing away from us. Just like the moon, Venus has phases. For the next few weeks, Venus is close to being directly between the Earth and the Sun so we are looking at the Venus’s back side. Its thin, crescent shaped back side. Look for Venus about one fist above the southwest horizon at 5 p.m. To the naked eye, it looks like a bright point of light. But with a small telescope, you can see that it does not look round just like the crescent moon doesn’t look round.
Tuesday: What would that special someone want to see on the back of Santa’s sleigh when she gets up early Christmas morning to eat one of Santa’s cookies? A fruit cake? No. A barbell? Maybe to work off the fruitcake. A subscription to The Daily Record? Of course. But what she really wants is a ring. And if she looks out a south-facing window, she’ll see her ring. Saturn the ringed planet, that is. Saturn is two fists above the south horizon at 7 a.m.
Wednesday: Where is the one who has been born King of the Jews? We saw Jupiter being eclipsed by the Moon in the east and have come to worship him” (Matthew 2:2, Bruce Palmquist version, informed by Michael Molnar). There are many theories as to the physical explanation of the Star of Bethlehem, the celestial object that guided the wise men to the location of Jesus. Some people think it was a recurring nova, a star that explodes. Some think it was a close alignment of bright planets. Some think it was a miracle that requires no physical explanation. In 1991, astronomer Michael Molnar bought an ancient Roman Empire coin that depicted a ram looking back at a star. Aries the ram was a symbol for Judea, the birthplace of Jesus. The Magi, or “wise men”, who visited the baby Jesus practiced astrology and would have been looking in that region of the sky for the king prophesied in the Old Testament. Molnar, a modern day wise person, used sky simulation software to model the positions of planets and the Moon in the region of Aries. According to his model, Jupiter was eclipsed, or blocked, by the Moon on the morning of April 17, 6 BC. Molnar’s theory is supported by a book written by the astrologer of Constantine the Great in 334 AD. The book describes an eclipse of Jupiter in Aries and notes a man of divine nature born during this time. See http://www.eclipse.net/~molnar/ for more information.
Aries and Jupiter make an appearance in the Christmas sky tonight. At 8 p.m., the dim constellation Aries is about six and a half fists above due south and Jupiter is about three fists above the east horizon.
Thursday: Mars is about four fists above the south horizon at 6:30 a.m.
Friday: Columbia the dove, representing the bird Noah sent out to look for dry land as the flood waters receded, is perched just above the ridge south of Ellensburg. Its brightest star Phact is about one fist above the south horizon at 11 p.m.
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.