Thursday, October 20, 2011

The Ellensburg sky for the week of 10/22/11

Saturday: “It’s a wonderful day in the neighborhood.” Constellations can be considered neighborhoods in the nighttime sky. But, the stars in those constellations are not necessarily neighbors in real life. For example, the bright stars in the constellation Cassiopeia range from 19 to over 10,000 light years away from Earth. One constellation that consists of real neighbors is Ursa Major. Or, more specifically, the Big Dipper. Five stars in the Big Dipper are all moving in the same direction in space, are about the same age and are all about 80 light years from Earth. “Please won’t you be my neighbor?” Skat, the third brightest star in the constellation Aquarius is a neighbor to these five Big Dipper stars, all of which are about 30 light years from each other. They are thought to have originated in the same nebula about 500 million years ago. Just like human children do, these child stars are slowly moving away from home. Skat is about three fists held upright and at arm’s length above due south at 10 p.m. The much brighter Fomalhaut is a fist and a half below Skat. And, it’s not fun being below Skat.

Sunday: Would you like to contribute to science? Participate in the Great World Wide Star Count this week. Go to to download instructions. Basically, you’ll count the stars you can see in Cygnus the Swan, a constellation that is nearly straight overhead at 8 p.m.

Monday: The Stargate movies and TV shows have access to a portal to other planets. Harry Potter has access to a portal to the Chamber of Secrets. You have access to a Portal to the Universe. This portal, available not in Moaning Myrtle’s bathroom but on the web at, is a repository of up-to-date astronomy news, blogs, and podcasts. A recent story highlights NASA’s Spitzer Space telescope’s discovery of a comet “storm” in a nearby star system that resembles what astronomers think occurred in our own solar system nearly four billion years ago. By studying the evidence of ice, organic material, and rocks near the one billion year old star Eta Corvi, astronomers may learn more about how the Earth was affected by a similar environment early in its formation.

Tuesday: Mars is five and a half fists above the southeast horizon at 6:30 a.m. The slightly dimmer star Regulus is a fist to the lower left of Mars.

Wednesday: Tonight’s Moon is new. Don’t bother looking for it. The new moon is the phase where the Moon is directly between the Earth and the Sun. Hence the side of the Moon facing Earth is not receiving any sunlight and cannot be seen. But it can be felt, especially by the oceans. The Moon is at perigee tonight meaning the Moon is the closest it will be this month. When the Moon is at perigee during the new or full stage, the high tides are especially high because the Sun, Earth and Moon are all lined up.

Thursday: This weekend is Halloween so make sure you load up on peanut clusters, almond clusters, and open star clusters. That last one will be easy (and cheap, actually free) because two of the most prominent open star clusters in the sky are easily visible in the autumn sky. The sideways V-shaped Hyades Cluster is two fists above due east at 10 p.m. Containing over 300 stars; the Hyades cluster is about 150 light years away and 625 million years old. The Pleiades Cluster, a little more than three fists above due east, is larger at over 1000 stars and younger. Compared to our 5 billion year old Sun, the 100 million year age of the Pleiades is infant-like.

Friday: Jupiter is in opposition tonight. No, that doesn’t mean it will disagree with everything you say. (Yes it does. No it doesn’t. Yes it does. No it doesn’t) Opposition means that a planet 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 of its orbital cycle. Jupiter is five and a half fists above due south at 1 a.m. daylight savings time which is midnight standard time. If you’d rather not stay up so late, you can find it three fists above the east-southeast horizon at 9 p.m.

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

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