suhuasky 发表于 2011-10-3 19:51
2011-10-1 21:45:40 徐智坚(785571361)
昨天那颗超级彗星
Hello all,
now looking at the latest C2 and C3 images:
[url=http://lasco-www.nrl.navy.mil/javagif/gifs/]http://lasco-www.nrl.navy.mil/javagif/gifs/[/url]
we have a nice CME developing around 21:30UT on Oct 1,
Could the comet encounter with the Solar atmosphere have been the cause?
The timing seems too much of a coincidence.
cheers,
Michael Mattiazzo
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"The CME will almost certainly be a coincidence, not related"
http://twitter.com/#!/SungrazerComets/status/120272236056821760
With there currently being up to 6 CMEs a day, there is no reason to think the
events need to be related.
-- Kevin Heider
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Indeed, CME are quite common and current theory certainly suggests that
there cannot possibly be any direct connection between such a solar event and
a Kreutz sungrazer's (pygmy or full-size example) perihelion passage, or
even possible collision with the solar surface. However, it is a singularly
odd coincidence that yesterday's large CME seems to have occurred very near
the perihelion point/solar impact zone of the comet's orbit at about the
correct anticipated time. I would further note for consideration that this
is definitely not the first such coincidence involving the nadir of a Kreutz
pygmy sungrazer's orbit and a CME occurring at a very similar location on
the solar surface at more-or-less the appropriate time. I have seen this
situation repeated several times now in SOHO sungrazer encounter images.
Now not for a moment would I seriously infer that such a tiny object,
perhaps no more than ten or twenty meters in diameter, could possibly disrupt
the solar atmosphere/surface on this enormous scale, but I do have to admit
that such seemingly coincidental occurrences do appear to happen more often
than the odds would tend to suggest. I think that it would be very
interesting to see the eventually determined orbital elements T and
particularly q
for yesterday's pygmy sungrazer.
Something else I felt was rather odd regarding this latest pygmy sungrazer
was its appearance on the SOHO images that were obtained shortly before it
disappeared behind the C3 camera's occulting disk. Now I fully admit to not
following pygmy sungrazers imaged by SOHO on any regular basis, but I have
examined the solar approaches of a fair number of the brighter ones over
the years. Therein, I normal see the bloom spikes associated with the
comet's head lengthen steadily as it brightens with final approach to
perihelion. At the same time the inner tail (that nearest the comet's head),
although
brightening too, normally remains much less luminous than the head.
In the case of yesterday's comet a significant portion of the inner tail
seemed to become at least as bright as the comet's head, producing a bloom
in the detector fully as intense as that of the comet's head, even after the
effects of the SOHO camera's radial gradient filter are considered. Might
this suggests the possibility that the head of the comet was actually in
the process of a massive disintegration event?
Are there perhaps any folks on Comets-ml that also participate in the
Sohohunter forum and might care to comment as to whether, or not, the
appearance of yesterday's comet on the SOHO C3 frames was fairly typical, or
perhaps
rather abnormal, in the last hours before perihelion? I'm sure that we
would all be interested to hear an opinion, or two, from some of the dedicated
members of that group.
J.Bortle
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