[meteorite-list] Fw: Comet 17P (Holmes) Visible Event !
From: Walter Branch <waltbranch_at_meteoritecentral.com>
Date: Wed, 24 Oct 2007 18:41:53 -0400 Message-ID: <023201c8168f$13376130$6101a8c0_at_BranchFamily> Hi Doug, You are right. This is a phenomenal event! First a supernova in NGC 7721 and now this comet suddenly brightens by several magnitudes. Unfortunately, all I have at present is a great view of the Great Cloudy (and rainey) Nebula. -Walter Branch (listing more meteorites on ebay) ________________________ ----- Original Message ----- From: "mexicodoug" <mexicodoug at aol.com> To: <meteorite-list at meteoritecentral.com> Sent: Wednesday, October 24, 2007 6:10 PM Subject: Re: [meteorite-list] Fw: Comet 17P (Holmes) Visible Event ! > Sure, and my questions were rhetorical more than anything else (not to > compare to Halley's Comet's size, or anything like that - they are miracle > specific). What would the wise kings in Biblical times have made of this? > (rhetorical) > > However, coma aside, a (now) 500,000 times increase in a few short hours > is quite remarkable by any standard - especially for something so far > away, and what has gone into this. This is not your typical comet event > as you know and is completely exploding off any graph for how magnitudes > of comets normally evolve - that is at the heart. > > This event will go down as one of the most spectacular, if not the most > spectacular, of its kind ever observed. If not for the prior much lesser > outburst recorded for this comet, I would be more inclined to think it was > an impact, than anything else. This is a comet that at closest approach > to the Sun only makes a Vesta (Main belt asteroid, maximum concentration > zone) distance. It virtually appeared out of nowhere into not only the > eyepiece, but also the naked eye at 2.4+ AU. Nonetheless, your point > about the coma is well accepted. > > I am blown away by rate at which it happened as the comet was already very > well far on its way out. and after all, it is traveling at 2.2 Km/s. > Best wishes, > Doug > > ----- Original Message ----- > From: "Chris Peterson" <clp at alumni.caltech.edu> > To: <meteorite-list at meteoritecentral.com> > Sent: Wednesday, October 24, 2007 4:33 PM > Subject: Re: [meteorite-list] Fw: Comet 17P (Holmes) Visible Event ! > > >> The size of the comet core is largely irrelevant. What matters is the >> size of the coma, since that's what is reflecting the light. And an >> active comet can easily have a coma many times larger than Mars. In >> reality, active comets are amongst the largest objects in the Solar >> System, even though their cores are amongst the smallest. >> >> Chris >> >> ***************************************** >> Chris L Peterson >> Cloudbait Observatory >> http://www.cloudbait.com >> >> >> ----- Original Message ----- >> From: "mexicodoug" <mexicodoug at aol.com> >> To: <meteorite-list at meteoritecentral.com> >> Sent: Wednesday, October 24, 2007 3:20 PM >> Subject: Re: [meteorite-list] Fw: Comet 17P (Holmes) Visible Event ! >> >> >>> Hi Again Listees, >>> >>> With regards to Comet 17P (Holmes) estimated at under 3.5 Km in >>> diameter, and being twice as far from the Earth as the planet Mars: >>> >>> How could it be one sixteenth as bright as Mars and an easy object in >>> the night sky with an almost Full Moon? No doubt it has a lot of ice >>> crystals or something white and reflective. A rought thought says that >>> in absolute terms it is one fourth the brightness of Mars if they were >>> at the same distance from us! This is because we perceive only 1/4 of >>> the light intensity due to the doubling of distance, >>> >>> It is it is hard to avoid the temptation of thinking this tiny body is >>> of relatively pristine material now confined to the Asteroid belt, but >>> before, from the Outer Solar System, and may, for once, given Jupiter >>> his dues, have been affected by a relatively close pass to the inner >>> Solar System, with Venus, Earth and Mars all aligned this month to exert >>> their gravitational attraction together. Not to mention all of the >>> scientists and collectors who would will material to Earth. >>> >>> The comet is over 40% further away from Earth as it is from Mars at the >>> moment, so I hope the guys with their hands on the controls of the Mars >>> rovers take a break and look up for us at MidSolnight, and that the Deep >>> Impact Crew is already into emergency overdrive to make the comparison >>> they will be held accountable for, now that there is a second chance >>> :-)... >>> >>> Best Skies and great health, >>> Doug >> >> ______________________________________________ >> Meteorite-list mailing list >> Meteorite-list at meteoritecentral.com >> http://six.pairlist.net/mailman/listinfo/meteorite-list >> > > ______________________________________________ > Meteorite-list mailing list > Meteorite-list at meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Wed 24 Oct 2007 06:41:53 PM PDT |
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