APOD: Comet and CME on the Sun (2011 Oct 05)

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Expand view Topic review: APOD: Comet and CME on the Sun (2011 Oct 05)

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by ems57fcva » Mon Oct 10, 2011 3:05 am

I think that the case against the two being related becomes much stronger when you can see the initiating region. Maybe this is coincidence, but with the occultation disk in place, what you see is comet heading and CME going out on the comet's trajectory. That makes asking if the two are related make some sense. Instead, this is a one-thousands coincidence caused in part by the Sun being active.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by iamlucky13 » Thu Oct 06, 2011 7:35 pm

Anybody who wants to offer an opinion on whether CME's can be caused by the sungrazer comets would be strongly advised to read this article first, by an astronomer who actually studies these comets:

http://sungrazer.nrl.navy.mil/index.php ... omets_cmes

His opinion (based on actually crunching some statistical data to try to find evidence that comets cause CME's), which I agree with, is that those few sungrazers (out of over 2000 known so far) that seem to disappear with close timing to CME's are easily explained by random chance. As he points out, on average there is a CME every 1-2 hours.

On that note, keep in mind that this video is a time-lapse. I looked up the timestamped images (available by using a date search here)The comet appears in the field of view at least 20 hours before it disappears behind the coronagraph. We're talking about a long period here, over which I saw 4 major CME's and quite a few smaller ones.
Ginger wrote:What is that blip that keeps moving to the left of the sun? Is it Venus?
Good guess, but it's actually Mercury. With it's short orbital period, it often shows up in LASCO images as it passes either in front of or behind the sun.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Ginger » Thu Oct 06, 2011 6:56 pm

What is that blip that keeps moving to the left of the sun? Is it Venus?

Tewfik

by neufer » Thu Oct 06, 2011 4:02 am

http://cometography.com/lcomets/1882k1.html wrote:
X/1882 K1 (Eclipse Comet or "Tewfik") <<Astronomers gathered in the region of Upper Egypt around mid-May 1882 as a total eclipse of the sun was predicted to occur on the 17th. About the middle of totality (about May 17.3), a luminous streak was observed near the sun.
M. Trépied first noted the comet to the right of the sun at a zenithal angle of nearly 90°. He referred to it as "in evident discordance with the rest of the corona." He said the idea of this object being a comet did not cross his mind until he saw the first of Dr. Arthur Schuster's photographs almost an hour after the eclipse. He said, "The brightness of the comet appeared to one to be of the same order as that at the exterior parts of the corona."
Photographs taken by Schuster showed the "streak" to be a comet. Schuster and Captain W. de W. Abney (both members of an English team) said, "The nucleus is exceedingly well and sharply defined, the tail is somewhat curved; it did not point toward the sun's centre, but in a direction nearly tangential to the limb. The extent of the tail was roughly two-thirds of a solar diameter." Schuster's photograph showed the comet's nucleus situated slightly more than one solar diameter from the sun's limb.
Schuster and Abney investigated numerous photographs of this comet and noted "a slight but progressive change in the comet's position." Since the comet was measured with respect to the moon's limb, they suggested this movement was due to the motion of the moon; however, even after this was taken into account, there still remained a change in the comet's distance from the moon's center which they suggested was "probably in part due to the proper motion of the comet, which in that case must have moved away from the sun during the eclipse."
The various eclipse parties met after the eclipse and jointly agreed to name the comet "Tewfik...in recognition of the Khedive's generous hospitality."
Initial investigations suggested this comet was probably comet Wells which had been well observed during the previous couple of months; however, calculations showed Wells would not have been in the proper position and would have been much fainter. Later suggestions were made to suggest this was a member of the sungrazing family of comets. During 1967, B. G. Marsden investigated the members of the sungrazing family. For this comet he said, "The tail was curved much as would be expected for a comet very close to the sun and rapidly approaching perihelion." The probable perihelion date, based on the assumption that the comet was a sungrazer, was 1882 May 17.5. During 1989, Marsden updated his research on the sungrazing comet family. The observation was only satisfactory enough to establish a possible perihelion date of May 17.46. For the orbit he conjectured that the comet was associated with comet C/1880 C1.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by ems57fcva » Thu Oct 06, 2011 3:57 am

Here is a full screen version of that frame. Once again, notice the anomalous flare at 280 degrees. I'm sure that this is the start of the CME coincident with the comet's death.
Attachments
Full screen version of the CME start frame
Full screen version of the CME start frame

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by ems57fcva » Thu Oct 06, 2011 3:46 am

Thanks for the suggestion of an attachment. Here it is.
Attachments
Frame of start of comet's CME
Frame of start of comet's CME

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by bystander » Thu Oct 06, 2011 3:09 am

Your attempt posting it as a url failed, too, as it is not publicly accessible. Might I suggest you attempt uploading it as an attachment.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by ems57fcva » Thu Oct 06, 2011 2:34 am

http://www.facebook.com/photo.php?fbid= ... e=1&ref=nf is the URL for the photo, since my attempt to to post it here has failed.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by ems57fcva » Thu Oct 06, 2011 2:33 am

Image

This is a frame from the video, admittedly embedded in the APOD page. Notice the flare at 280 degrees (just above the left limb). That is the start of the cometary CME, and it is in a place that is quiescent both before and afterwards. I assume that this is in part the momentum of the now exploded comet. The result is a very short burst that is very unlike other CMEs. I get the feeling that relatively little material was in the CME and that it had a huge spread, whereas "normal" CMEs appear to be much more massive and much more directed. The flaring of the established active areas then may or may not have been associated with the comet, but if not that is fine. It is this very quick flare that seems to be comet created.

I really get a sense of the Sun being kicked, and sending stuff off in many direction for a moment as a result. I admit that it was not much of a kick, but then again how much mass is in a small comet, and how does that compare to the mass of Sun's corona, which is just a bunch of gas? I think that you may find that the comparison is not as unfavorable as one may expect at first.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by yellowbag » Thu Oct 06, 2011 12:52 am

this is too much of a coincidence thAT this film is on here today. just yesterday night on History Channel show Weird or What, this was claimed by one scientist/astronomer to be ufo's crashing purposefully into the sun to cause CME's. if anyone can find last night's show on this, please check it out!

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Chris Peterson » Thu Oct 06, 2011 12:39 am

joesun wrote:this has happened three times this year. a comet and cme simultaneously. Impossible that this is coincidence. Gimme a break.
I'll buy that if you are willing to back up your point with some solid statistics. Otherwise, I think I'll stick with the expert viewpoint and common sense and continue to believe that coincidence is by far the best explanation offered so far.
Neurtons go faster than light...
No, they don't. Neutrons don't, and neutrinos almost certainly don't either (and if it turns out that neutrinos actually do, the amount they exceed c by is extremely small.)

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Wolf Kotenberg » Thu Oct 06, 2011 12:00 am

sometimes beliefs are held so tightly, excursions into the unknown and acceptance of such unknowns are impossible to accomplish. Pass me the ice cold one as i watch that neutrino whgizz by me at the speed of light, or above.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by AstronomyFan » Wed Oct 05, 2011 11:57 pm

I like the video :clap: :D

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by joesun » Wed Oct 05, 2011 11:56 pm

this has happened three times this year. a comet and cme simultaneously. Impossible that this is coincidence. Gimme a break. Neurtons go faster than light and comets do cause cme's!!!

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Boomer12k » Wed Oct 05, 2011 11:48 pm

THAT...is just what "THEY"....want you to believe.....



:-------====== *

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by hexalm » Wed Oct 05, 2011 8:02 pm

neufer wrote:
Psnarf wrote:
Whatever it was, comet or asteroid, it had to have vaporized high above the surface. I'll go out on a limb here, I think it is impossible for the object to have caused the CME. My feeble grasp of plasma physics leads me to doubt that comets or even asteroids can last very long in a two-million-degree Kelvin environment. If the object did strike the surface causing the CME, it's gotta be space monkeys. No wonder they're so difficult to find, they're hiding just below the surface of the sun. :b:
I too doubt striking the surface would have any effect.

However, if the comet were to explode into a high density plasma at some very critical place in the coronasphere it might just trigger the reconnection of coronal magnetic lines leading to a CME.
I might be oversimplifying, but it would take EM radiation about 5 seconds to go through the sun (unhindered in a vacuum, anyway), and around 15s to go around it. What I can't seem to remember is if snapping magnetic field lines are limited to the speed of light, or if they sneak around it somehow.

I would assume they can't transmit information to the opposite side of the sun instantaneously, though the only info I can find regarding that is here: http://www.sciencedaily.com/releases/20 ... 233737.htm, in the context of CME features moving at 1/2 million mph (nowhere near the speed of light, not sure if that specifically refers to magnetic field lines, though).

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by neufer » Wed Oct 05, 2011 7:40 pm

Psnarf wrote:
Whatever it was, comet or asteroid, it had to have vaporized high above the surface. I'll go out on a limb here, I think it is impossible for the object to have caused the CME. My feeble grasp of plasma physics leads me to doubt that comets or even asteroids can last very long in a two-million-degree Kelvin environment. If the object did strike the surface causing the CME, it's gotta be space monkeys. No wonder they're so difficult to find, they're hiding just below the surface of the sun. :b:
I too doubt striking the surface would have any effect.

However, if the comet were to explode into a high density plasma at some very critical place in the coronasphere it might just trigger the reconnection of coronal magnetic lines leading to a CME.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Psnarf » Wed Oct 05, 2011 5:01 pm

The STEREO views are so cool! You can see the object flying above the surface of the sun before vanishing near the center of image. Whatever it was, comet or asteroid, it had to have vaporized high above the surface. I'll go out on a limb here, I think it is impossible for the object to have caused the CME. My feeble grasp of plasma physics leads me to doubt that comets or even asteroids can last very long in a two-million-degree Kelvin environment. If the object did strike the surface causing the CME, it's gotta be space monkeys. No wonder they're so difficult to find, they're hiding just below the surface of the sun. :b:

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Harry TenHerons » Wed Oct 05, 2011 4:16 pm

Way to knock it out of the park, APOD ! Yay !

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Beyond » Wed Oct 05, 2011 3:50 pm

:lol: I think it grabbed the cat image just a little toooo hard and stretched it's neck a bit :!:

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by owlice » Wed Oct 05, 2011 3:40 pm

Orin, yes, those are the images that user is seeing INSTEAD of the day's APOD. The backgrounder program downloads (or tries to download) the current APOD image and makes it a computer's background image. When an APOD is not a static image, the backgrounder program grabs the first image it can find in the text and downloads that instead. If one doesn't know it does that, confusion results!

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by orin stepanek » Wed Oct 05, 2011 3:36 pm

owlice wrote:michaelpat, you are probably using the APOD backgrounder program, which was written before videos became so common on the Web. This program doesn't handle videos, and when something other than an image is the day's APOD, the backgrounder program looks for the first available image amongst the links. See here for more information.

The shot of the fallen trees WAS the APOD for that day. You might want to look at APOD on the web on occasion, as that is the medium for which the site is designed. It's great to have the other options, but sometimes they just don't work as well as the original.
owlice I thought he was referring these links that were in the explanation!

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by nstahl » Wed Oct 05, 2011 3:08 pm

Thus are religions founded. One event then another and it's (too) natural to assume causation. If there was video going around of a CME followed by a comet there'd be a few people thinking CME's cause comets.

Re: APOD: Comet and CME on the Sun (2011 Oct 05)

by Wolf Kotenberg » Wed Oct 05, 2011 3:06 pm

celestial bankshot. There are rumors the moon was created by a bankshot

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