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Old 25-October-2007, 02:02 AM
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Default Comet 17/P Holmes in outburst

I just took several shots of Comet 17/P Holmes which is currently in outburst. It's easily 3rd mag, if not brighter. I posted the images on my blog.

Here is one of it with Cassiopeia. The contrast could be better, but it's there! Unfortunately, the Moon is nearly full, so contrast is an issue. Go to the blog post for better contrast images.
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Old 25-October-2007, 04:44 AM
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I managed to find it in my 8" SCT (once I got my finder realigned ).

I don't have my SLR with me and my power cord is MIA too, so I just tried to snap a shot of it holding the camera up to the eyepiece. I got a few decent images representative of what I saw in the eyepiece. Here's the best of 'em.
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Old 25-October-2007, 05:50 AM
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Thanks VR, you just saved my the trouble of dragging my 10" dob out into the street. I wouldn't see anything better than that in my light polluted Bay Area sky.
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Old 25-October-2007, 06:08 AM
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Here's my version. Dang thing was so bright I had to use 0.5 second sub exposures or my non blooming camera BLOOMED on the core of this guy. That's bright. This is 11 half second shots plus 4 one second shots in each RGB color. Taken through clouds that soon shut me down. How bright is this guy?

This guy is currently about 2.45 AU out there and it is receding. That would put it in the asteroid belt. So did it get belted? Sorry. I know it's done this before so likely it's own doing but still you have to wonder.

14" LX200R

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Old 25-October-2007, 12:18 PM
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Thanks everyone and especially Rick, best pic I've seen yet. The blasted thing sits on my north east horizon so keep posting guys!

Kind regards
Matt
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Old 25-October-2007, 01:23 PM
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Not sure where the green came from, but here's my photo.
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Old 25-October-2007, 02:11 PM
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Nice shot jp.

I'm again struck by how symmetric the halo appears to be. Through my 8" it looked nearly perfectly round with a tiny bit of extention that I attributed more to reflection in the eyepiece than any natural extention.

This seems rather odd to me. Outgassings wouldn't be so symmetric from what I understand. Sure they can redistribute themselves, but that much this quickly?! The same for some sort of collision. Makes me wonder...

Seeing your images that confirm that nice symmetric halo only confuses me more.
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Old 25-October-2007, 02:23 PM
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Quote:
Originally Posted by VoijaRisa View Post
I'm again struck by how symmetric the halo appears to be.
Indeed - it seems like that on all the pictures. Is there a known projectory of the comet?

btw: great pictures!
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Old 25-October-2007, 05:03 PM
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4 hours after I took the image posted earlier in this thread I tried again when the clouds opened a hole. I used 1x1 binning for 0.5" per pixel resolution. Clouds only opened long enough for a black and white shot. Boy has it changed in those 4 hours. Now there's a ring that was only hinted at in the earlier image and it is off center the opposite direction. This guy seems to be making symetrical outbursts. For some reason, when converted to JPEG the nucleus goes from a near point to a blob that runs down and to the right (southwest). There's a bright jet in that position on the 16 bit tiff. I can't seem to get the JPEG to work right. The compression in Photoshop seems not to understand comets and I'm due to hit the road in 20 mintues so no time to figure it out.

Taken at 6:40 UT Oct 25, 2007

Rick
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Old 26-October-2007, 08:24 PM
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I took some shots last night through my 12.5" using the camera mounted on a tripod. Only a couple turned out looking like what the eyepiece view was. Here's one. The yellow color by eye was amazing. Must be lots of dust in the outgassing.
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Old 27-October-2007, 01:03 AM
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Hmm, looks like a dandelion puff!
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Old 27-October-2007, 02:07 AM
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Great pictures. Keep them coming . . .
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Old 27-October-2007, 02:07 AM
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Lots of great photos here, You all did great guys Welldone!
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Old 27-October-2007, 01:20 PM
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I managed to get this pic under a nasty sky filled with haze. And the vewy vewy ugly full moon.
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Old 27-October-2007, 01:31 PM
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Welcome to the new members with their excellent pics.

Thanks for all the great pics guys.
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Old 28-October-2007, 02:19 AM
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hey guys.
i got this 40mm telescope( i know its not powerful), so im wondering if it is possible for me to see it?
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Old 28-October-2007, 02:22 AM
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Quote:
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I managed to get this pic under a nasty sky filled with haze. And the vewy vewy ugly full moon.
That's a great picture!
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Old 28-October-2007, 02:28 AM
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Quote:
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hey guys.
i got this 40mm telescope( i know its not powerful), so im wondering if it is possible for me to see it?
It's a naked-eye object at approx magnitude +2.5. so you'll be able to see it just fine. Depending on the quality/focal length of your scope you should be able to get a solid 10x magnification. You won't see a lot of detail - probably just a fuzzy dot. You won't see the image as large as the photos here that were taken with much larger scopes. You're also far enough north to get a good view. Go for it - you've got nothing to lose by trying. Let us know what you see . . .
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Old 28-October-2007, 03:53 AM
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Just watch it grow! This set of images is displayed in matching logarithmic scales, and taken 20 hours apart today. To first order, one expects the total brightness to be constant, and the surface brightness to drop as the square of the linear expansion factor (as long as the dust particles stay the same). To my eye, it was distinctly fuzzy with the naked eye tonight, but not particularly less prominent overall than last night.

I am struck that the offset of the brightest diffuse region from the apparent nucleus is more or less perpendicular to the project orbital motion (which is nearly to the right in these images). This is not to suggest that I have any profound idea as to what that means. However, I am now convinced that the ringlike structures are real, even without having a chance to do any detailed image modelling or filtering...
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Old 28-October-2007, 04:39 AM
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Quote:
Originally Posted by ngc3314 View Post
Just watch it grow! This set of images is displayed in matching logarithmic scales, and taken 20 hours apart today. To first order, one expects the total brightness to be constant, and the surface brightness to drop as the square of the linear expansion factor (as long as the dust particles stay the same). To my eye, it was distinctly fuzzy with the naked eye tonight, but not particularly less prominent overall than last night.

I am struck that the offset of the brightest diffuse region from the apparent nucleus is more or less perpendicular to the project orbital motion (which is nearly to the right in these images). This is not to suggest that I have any profound idea as to what that means. However, I am now convinced that the ringlike structures are real, even without having a chance to do any detailed image modelling or filtering...
With that much increase in less than one day, is the magnitude still considered 2.5 ?
I can see it with my naked eyes even with the moon in the sky. It's pretty clear here on the coast tonight. Like someone said earlier......... looks kind of like a dandelion with my 8 power binoculars.
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Old 28-October-2007, 06:14 AM
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I just saw 17/P tonight...she is BEAUTIFUL. Very bright--easily visible with moderate light pollution and a nearly full Moon, and the declination could not be more favorable at this time of year. Though I'm no expert in guessing magnitudes, it looks nearly as bright as Alpha Persei itself, which would peg it at solid second mag. Beautiful in 10x50s, and impressive even in my 60mm at 30x; very symmetrical coma, with a noticeably off-center brightness at its nucleus. If my eyes don't deceive me, I even saw hints of shell structure myself.

An astronomical treat all around, and my first periodic comet.
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