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  •  Comet Ison and Mars Oct.18th (11+ / 0-)

    If you haven't heard yet a comet named Ison is streaming toward earth. It has the potential of being the brightest in modern history. Some estimates have be a magnitude of -12 or above around the end of November. That would make it as bright as a full moon. But don't believe all the hoopla. No one knows just how bright it will be. It might be a big bust like Kohoutek back in the 70's. A realistic value of -8 is a good guess. That would be brighter than Venus and would be visible in the day time. But I should caution that when it reaches that brightness it will be very close to the sun, and as I am sure you know, you really don't want to look directly at the sun.

    Is also possible that it will get so close to the sun that it will break up.

    Around Oct. 17 - Oct. 19 it will be very close to Mars. It will still be too dim to view with the naked eye, but should be visible through binoculars or even a small telescope. At it's closest it will be just over one square degree from Mars. This is will not only make it easy to find, but will also offer a possible pleasing image of a planet and comet in one frame.

    The average binoculars have a filed of vision of about 6.5 degrees, so you will see a orange dot and a blurry thing to its left. Telescopes typically have a much smaller filed of vision with a 20 mm eye piece giving something like 0.5 degrees. With a 30 mm-40 mm eye piece you should be able to see both. It will raise at about 4:00 A.M. in the East and by 6:00 a.m. shortly before the sun raises it will be at about 107 degrees and 34 degrees up in the sky.

    Using Cartes de Ceil, this is what you would see at 1.5 degrees on Oct. 18th.

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    It is possible to read the history of this country as one long struggle to extend the liberties established in our Constitution to everyone in America. - Molly Ivins

    by se portland on Sun Apr 28, 2013 at 12:07:34 PM PDT

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