Comet ISON update

The Hubble Space Telescope has taken new images of Comet ISON, a sungrazing comet that, it is hoped, will become the brightest comet in living memory this December. The video above is probably the best look we’ll get at ISON until it comes out from behind the Sun in September. Looks like so far, so good.

On November 28, Comet ISON will pass less than the Sun’s own diameter from the Sun’s surface, but it will probably survive this intense heat because it’s simply too big to melt all at once. If it does…and if we’ve called it right…it will dominate the northern skies after sunset here on Earth for the next month. In the extreme case, it could become even brighter than the Moon.

The reason ISON is expected to be so spectacular lies in its orbit. Its orbit is very nearly a parabola. That means it started almost “infinitely” far away, in the Oort Cloud, is falling toward the Sun, and would fly back to the Oort Cloud if left to its own devices. But most comets aren’t like than. When a comet passes through the inner Solar System, the gravity of the planets either bends its orbit into a long ellipse or kicks it out of the Solar System entirely.

ISON’s nearly parabolic orbit suggests that it is a virgin comet that has never come near the Sun before. That means it could be loaded with fresh ice that will vaporize and form an especially bright coma and tail, making ISON “The Comet of the Century”. So keep watching the skies.

For those of you who are wondering about my Camp NaNoWriMo exploits, I wrote 15,448 words in the first 10 days of the month, which is only 681 behind schedule. I am cautiously optimistic about finishing it.

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About Alex R. Howe

I'm a full-time astrophysicist and a part-time science fiction writer.
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3 Responses to Comet ISON update

  1. fahrusha says:

    This is very exciting. I hope it is a big show. Are you familiar with the theory of Panspermia as espoused by Hoyle and Wickeramasinghe? We could be in for more than we bargained.

    • Alex R. Howe says:

      I’ve always considered panspermia to be something of a long shot. In any case, Comet ISON, despite its brightness, won’t be coming anywhere near Earth.

      • fahrusha says:

        Panspermia is a fascinating theory, but a theory still. According to my understanding of the theory, the comet doesn’t have to actually pass close to the Earth but simply pass through the plane of the Earth’s orbit for the particles from the comet to eventually descend into our atmosphere. I guess time will tell. Thanks for your reply.

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