Bakersfield College

November 17, 2012

Bakersfield Night Sky – November 17, 2012
By Nick Strobel

Earlier this week I took a call from someone who wanted to buy a star name as a gift for their friend. Requests like that send some planetarium directors into a frothy fit because those star registry companies are scams. Fortunately, the caller reached someone a bit calmer. This provides a good opportunity to remind you all that the star registry companies are not officially-recognized by anyone (other than themselves) and that the star names they sell you are NOT used by anybody else, especially not any astronomer or astronomy organization. The only organization authorized to give names to objects and features on planets and moons is the International Astronomical Union, the worldwide federation of astronomical societies. Those names are never sold. Very often the stars used by the star registry companies will be some extremely dim star that cannot be seen without a telescope. You might get a fancy certificate from the company suitable for framing but you could save yourself the money and create your own certificate for your friend. Or you can make a donation to the William M Thomas Planetarium through the Bakersfield College Foundation, get a tax write-off, and I'll give you a certificate! As I eye the aging video all-dome projector and the empty state budget, I'd be happy to get some help in upgrading the all-dome video projector. For more on the naming of stars, see the International Planetarium Society's statement on star naming or the IAU's naming FAQ page.

The latest buzz in exoplanet news is HD 40307g. It is the sixth planet discovered orbiting the star, HD 40307, a star slightly cooler than the Sun and 40 light years away from us. HD 40307g orbits within the star's habitable zone, so if the planet is rocky, it would have just the right temperatures for liquid water to exist on the surface. The planet was discovered from how it tugs on the star gravitationally and makes the star wobble around a point between the planet and the star. The size of the star's wobble from HD 40307g is pushing the limits of detection, so the discovery needs to be confirmed by other groups and follow-up observations and analysis are needed to pin down its mass. The best estimate currently places it between 7 to 10 times the mass of the Earth—that is in the "super-Earth" category and not in the "mini-Neptune" category. It is far enough from its star that it could be imaged directly by future proposed space telescopes.

On the last Thursday of November and the first Thursday of December, the Planetarium will be showing the ever-popular "Season of Light". After a tour of the night sky with the Chronos projector, the "Season of Light" show on the all-dome video projector will trace the history and development of many of the world's most endearing holiday customs along with the astronomical explanation for why the seasons change throughout the year. The show ends with one possible explanation for the "Star of Bethlehem". I discuss other possible explanations for the "Star of Bethlehem" in an article posted on my Astronomy Notes site.

The Leonid meteor shower peaked in the pre-dawn morning of today (November 17th) but the shower was not expected to deliver much this year. The Leonid meteor shower happens every year at this time when the Earth runs into the dust trail left behind by Comet 55P/Tempel-Tuttle. The dust grains in the Leonids travel the fastest of any of the meteor showers: an impressive 44 miles/sec through the upper atmosphere. The meteors appear to streak out of a point in the Sickle part of Leo. The next meteor shower will be the Geminids that peak on December 14th. The Moon will not be in the sky at all for the Geminids this year, so it promises to be a great show.

The super-bright star you see low in the east starting at about 7:15 PM is the king planet, Jupiter. Jupiter is still between the horns of Taurus and continues moving backward (retrograde) or westward among the stars. By 10 PM Jupiter will be half-way up in the sky and the constellations Orion and Gemini will be about a third of the way up in the sky as shown in the second chart below. Earlier in the evening around 6 PM, you might be able to spot Mars low in the southwest next to the Teapot part of Sagittarius. The thin Waxing Crescent Moon is above on the edge of Sagittarius and it will set by 9 PM.

In the early morning sky, Venus continues to close in on Saturn for their conjunction on November 26th as shown in the first chart below. Tonight they are about a fist width (held at arm's length) apart from each other but on the pre-dawn morning of November 26th, they'll appear to almost touch each other on our sky (in three-dimensional space, they are actually about 856 million miles apart from each other). By the end of November, Mercury will become visible just before sunrise among the stars of Libra.

Want to see more of the stars at night and save energy? Shield your lights so that the light only goes down toward the ground. See www.darksky.org for how.
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Nick Strobel
Director of the William M Thomas Planetarium at Bakersfield College
Author of the award-winning website www.astronomynotes.com

Kern Community College District