Wednesday, December 2, 2009

The Ellensburg sky for the week of 12/5/09

Saturday: The earliest sunset of the year occurs this week, about 4:17 p.m. This seems odd because the shortest day of the year, the winter solstice, isn’t for about two more weeks. 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 leading edge of the analemma, the first section to go below the horizon.

Sunday: Mars, the bright star Regulus, and the Moon make a small triangle in the sky tonight. At 11 p.m., Mars is about one fist to the upper left of the Moon and Regulus is a little less than a fist to the lower left of the Moon. They are about one fist held upright and at arm’s length above the east horizon.

Monday: “Hey baby! What’s your sign?”
“Ophiuchus, of course”
The Sun is in the same part of the sky as the stars of Ophiuchus from about November 29 to December 17. This is what astrologers mean when they say the Sun is “in” a constellation. Thus, if you were born between these dates, you should be an Ophiuchus. The fact that the horoscopes never list Ophiuchus is a major flaw of astrology. Astrology says that some of our characteristics are based on the location of the Sun at our birth. How can astrologers leave out three weeks from their system? That is like a scientist saying she can explain the results of her experiment every month of the year except early December. Ophiuchus was a mythical healer who was a forerunner to Hippocrates. According to myth, he could raise people from the dead. Maybe that is why he is ignored by astrology. Raising people from the dead is much less impressive than giving highly personal advice such as “Today is a good day to watch your finances.”
The bright stars of Ophiuchus rise just before the Sun. Rasalhague (pronounced Ras’-al-hay’-gwee), the brightest star, is about one fist above the east horizon at 6:30 a.m.

Tuesday: This morning’s nearly last quarter Moon is in the constellation Sextans the sextant. I know. I know. Right now, 100,000 Daily Record readers are asking “What the who?”. Sextans is a faint constellation below Leo the lion. It is one of seven constellations proposed by Polish astronomer Johannes Hevelius in the 1600s. He used a sextant to measure star positions.

Wednesday: Jupiter is two and a half fists above the west-southwest horizon at 6 p.m.

Thursday: Saturn is about a fist above the Moon at 6 a.m. They are in the south-southeast sky.

Friday: When Galileo aimed his telescope towards the sky, he knew of only one Sun-like star: the Sun. By the early twentieth century, Annie Jump Cannon, Williamina Fleming and others had developed a scheme for classifying stars so astronomers could identify other Sun -like stars. But it wasn’t until the last few years that astronomers have discovered planets around some of those Sun -like stars. As of this week, at least five Sun -like stars have at least two planets orbiting them. These 10 planets are unlikely to have life as we know it because they are all giant planets, some larger than Jupiter and some extremely close to their host star. But in the next few years, satellites such as Kepler will start imaging Earth-sized planets around these stars. For more information about these and other exciting new worlds, go to the last Hot Topic of the International Year of Astronomy at

The positional information in this column about stars and planets is typically accurate for the entire week.

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