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Nov 22 2013

The moment of truth approaches for ISON

Thanks to some generous readers yesterday, this will be the last day before Thanksgiving Week I’ll have to bleg for money. The fact is blogging pays about a tenth what it did before the Great Recession and atheist activism isn’t exactly, as The Jerk would say, a profit deal. I’ll have a snail mail address soon for those of you who don’t use Paypal. For the rest, please send small dollar donations to DarkSydOtheMoon-at/aol-com. No amount is too small or too large. For an update on deep space visitors, go below.

While you’re shopping, eating, napping, or having to work this holiday season, cast your eyes upward over the next few weeks and you might catch sight of a bonafide deep space dweller. It’s Comet C/2012 S1, better know as ISON. You won’t get another chance to see this visitor, if ISON survives a close pass by the sun on Thanksgiving Day, it’ll streak by earth close enough to see with the naked eye or a small pair of binoculars, on its way to the stars:

Some comets are on long, elliptical orbits dropping them in to the inner solar system before sailing them back out to the depths of space. There, they slow, stop, then fall once again back into the warmth and light. Comet Halley, for example, is on a 75-year orbit that takes it out past Neptune.

But some are more extreme. If they get an extra kick on their way in — perhaps from a collision, or a boost by a planet’s gravity — their elliptical orbit gets turned into an open-ended hyperbola: they have more than enough energy to leave the solar system forever. Once they’re gone, they’re gone.

At it’s peak velocity during its closest dip to the fiery sun’s surface, ISON or its remains will be traveling at a sizzling 225 miles per second. That’s 0.1% of c, where c denotes the speed of light, for you physics fans and wonder junkies.

5 comments

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  1. 1
    Randomfactor

    Wondering…is this the fasted “observed” speed for a solar-system object?

  2. 2
    Stephen "DarkSyde" Andrew

    It’s the escape vel of the sun. So any object that falls in from several AUs will achieve it, including all sundiving comets and asteroids. For very massive stars and neutron stars, that velocity is considerably higher still. For black-holes it theoretically hits 99.9 c at the event horizon.

  3. 3
    F [i'm not here, i'm gone]

    I think it is particularly cool that ISON is a fresh comet. I hope we get metric craptons of data.

  4. 4
    StevoR : Free West Papua, free Tibet, let the Chagossians return!

    ISON or its remains will be traveling at a sizzling 225 miles per second. That’s 0.1% of c, where c denotes the speed of light, for you physics fans and wonder junkies.

    Did not know that. Thanks.

  5. 5
    StevoR : Free West Papua, free Tibet, let the Chagossians return!

    PS. NASA has images from the STEREO sunwatcher probes of Comet ISON here :

    http://www.nasa.gov/content/goddard/nasa-releases-comet-ison-images-from-stereo/index.html

    With Encke co “starring” (Comet~ing?) too.

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