And It Lives! Comet ISON Recovered

The small blurry spot is almost certainly Comet ISON in this photo taken on the morning of August 12. The fuzz was at the comet’s predicted position. Click photo for complete details on Gary’s observation. Credit: Bruce Gary

An Arizona amateur appears to be the first person to spot Comet ISON again after its long spell in the solar glare.  Bruce Gary used an 11-inch telescope to photograph a faint bit of fuzz at the correct position in Cancer the Crab below the constellation Gemini. Since ISON was only a few degrees above the horizon and twilight already underway, this was quite a feat. Gary is still awaiting confirmation that his pictures really do show the comet and not some camera flaw, but it appears to be the genuine item.

We can all breath a sigh of relief that ISON has survived this long. It’s been out of view of ground-based telescopes since late May when Earth’s orbit put the sun between us and the comet. Lost in the glare of day and twilight, no one knew exactly what our celebrity was up to. For all we knew, it had broken up in to pieces and disintegrated, an infuriating habit shared by many comets.

An armada of spacecraft, space observatories, a balloon mission and even the Mars Curiosity Rover will be following Comet ISON as it draws nearer to the sun in the coming weeks and months. Credit: NASA

Gary’s photo is important for another reason. It gives astronomers another precise position they can plunk into their computers to better calculate ISON’s orbit. Not that the comet’s going to veer off in another direction but activity on a comet’s surface – the vaporization and jetting of ice and dust – can subtly alter a comet’s predicted path. The more observations, especially ones like Gary’s coming after a long data drought,  the better we can keep track of ISON’s future moves.

Comet ISON has finally crept back into dark skies before the start of dawn, but  faintness and low altitude will make it a challenge for the next two weeks. Created with Stellarium

So how bright is this thing? Astrophysicist Karl Battams notes that the comet appears to have brightened according to predictions. That would put it between 12.5-13.0 magnitude. If ISON were high in the sky, amateur astronomers with 10-inch and larger telescopes would have no problem spotting it, but our favorite fuzzball still lingers low in the northeast near the start of dawn. Thick hazy air near the horizon dims it another 2-3 magnitudes.

Atmospheric seeing – the steadiness of the air –  gets worse the lower you look, turning stars and comets alike to mush.  Someone with a fairly large telescope will soon enough see it with their eyes as opposed to recording it in a photo.

For the Upper Midwest, ISON is 4 degrees high at the start of dawn tomorrow morning, too low to spy in most amateur telescopes. But hang in there. Once the waning moon and its aura of glare leave the scene at the very end of August, conditions quickly improve. Assuming the comet continues to brighten, anyone with dark skies, a good map and an 8-inch or larger telescope should get their first look at this much-anticipated object.

6 Responses

  1. Edward O'Reilly

    Hi from Saint John,New Brunswck,Canada,I really enjoy your astro discussions and commentaries and refer to it all the time.What do you think of the somewhat pessimistic outlook on Ison,as expressed in Sky and Tel? Personally,I think they’re being a bit too gloomy;the comet,at ~13th mag,would seem to be right on course.And shouldn’t recovering it 2 weeks early be a source for optimism? What do you think?

    1. astrobob

      Hi Edward,
      Thank you and I’m happy you enjoy the blog. Sky and Tel has John Bortle, one of the best comet people out there, and he tends to be right. I think that if ISON survives perihelion intact and holds together in the weeks after, it will become a spectacular object. If it breaks to bits at or soon after perihelion, we’ll have a nice show but not the spectacle hoped for. Either way, amateurs will have a blast following it no matter its brightness. It worries me a bit that it’ll be at its best in the early morning during a cold, relatively cloudy time for our region, but I’ll be out every clear night I can. I saw ISON last winter and I’m primed to see it again this month. As for the public, that’s up to us as amateurs. If we shoot straight and provide opportunities for people to see it, they’ll come away touched by the memory of a nice comet.

      1. Edward O'Reilly

        Hi, thanks for the response.I’ll certainly be watching for it,as well. Do you think that recovering Ison a bit early is a good sign that its brightening is on course? Thanks again.
        -Ed O’Reilly

        1. astrobob

          Yes! Matter of fact, if it turns out to be 13th magnitude, that’s a great sign, since it had plateaued around 15 for months after discovery. It might be the hoped-for sign that water vaporization has begun, which should provide a noticeable increase in brightness.

          1. Edward O'Reilly

            That’s great! I know comets can be fickle and fragile but I do have a good feeling about this one.Time will tell.

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