[meteorite-list] Is Vesta Mong Nong?
From: MexicoDoug <mexicodoug_at_meteoritecentral.com>
Date: Sun, 24 Jul 2011 02:34:39 -0400 Message-ID: <8CE17E2DFD4712B-6A4-23465_at_webmail-d174.sysops.aol.com> "when an object is not in a tightly bound orbit confiscation and just gets "pushed" rather than crushed?" That was a question out of left field! I'm not familiar with orbit confiscations, but, if you mean that the object is free floating far away ... That would be the case of something distant from the Sun, at the edge of the gravitational well if you like graphic thoughts. However, gravitational attraction at a given distance in AU from the Sun or other main body is only a function of the object's mass. That said, if the impactor is playing "catch-up" to the target, of course you will have a lower energy collision vs. the head on case: everything is relative. In the unlikely (but possible, especially in some special cases that could be dreamed up) case you had two objects traveling at a tiny difference by essentially the same speed and co-orbital, they'd probably either turn into a dumbbell shape or one would form a captured moon-situation. What you want to consider is the kinetic energy of the impact which is successfully transferred/damped between the objects. The kinetic energy will be proportional to mv^2 and will give you, in terms of physics, the "work" done ... i.e., a transfer of energy from one to the other; that is, how much moving and shaking and excavating and phase changing and heating and other energy forms is done, including changes in potential energy. In plain English, a smack is a smack, and the first order of concern is the relative velocity. If two objects happen to have their directions aligned and one approaches the other rear side with a difference of 10 km/s, those damages are the same as a head on collision when the difference is 10 km/s. It may be more likely that a rear collision happens at a slower relative velocity but it is hard for me to think that a 10 km/s push would be any different than a 10 km/s head on. At a slower velocity, e.g. 1 km/s, it might very well transfer a higher proportion of the impactor's energy into orbital speed (at half the speed, for example, the impact would take longer and likely excavate less - but the overall energy would be less too: At slower relative speeds, less energy is exchanged and less damage will be done. Same concept works for when meteorites are more easily surviving the landing on earth. But lots of billiard-inspired or multiball roulette: http://www.youtube.com/watch?v=7Ui0Wxoz-BQ#t=2m45s Variations on the theme are possible and impact guys can maybe make a living looking at these scenarios in hopes of pairing them to the real worlds. A glancing blow, for example will allow the impactor to possibly only transfer part of its energy and generally go on its way with the remainder of it. The there is the revolving about the axis of the target which is a separate component of kinetic energy. A glancing blow in the direction of revolution will force a bit of refining/expanding on the timing of the transfer of energy of impact since kinetic energy. It seems clear to me that if you could come up with circumstances to prolong the collision time, a higher percent of the impact energy can be used for changing spin or speed. But just because 70% of "X" megatons goes into speeding up or slowing down or spinning, etc., doesn't mean that for a higher energy collision that 10% of "Y" gigatons won't skunk the former. Confusing until the initial conditions are defined ... 2c Kindest wishes Doug -----Original Message----- From: John Lutzon <jl at hc.fdn.com> To: meteorite-list at meteoritecentral.com Sent: Sat, Jul 23, 2011 12:41 am Subject: [meteorite-list] Is Vesta Mong Nong? ----- Original Message ----- From: "John Lutzon" <jl at hc.fdn.com>? To: "Galactic Stone & Ironworks" <meteoritemike at gmail.com>? Sent: Saturday, July 23, 2011 12:28 AM? Subject: Re: [meteorite-list] Is Vesta Mong Nong?? ? ?Hi Mike, List? ? ?Case in point.? ? ?http://apod.nasa.gov/apod/ap970630.html? ? ?John? ? > ----- Original Message ----- > From: "Galactic Stone & Ironworks" <meteoritemike at gmail.com>? > To: "John Lutzon" <jl at hc.fdn.com>? > Cc: "brian burrer" <brimane at gmail.com>; > <meteorite-list at meteoritecentral.com>? > Sent: Friday, July 22, 2011 11:52 PM? > Subject: Re: [meteorite-list] Is Vesta Mong Nong?? >? >? >> Hi John and List,? >>? >> John said - "So, are impact forces mitigated when an object is not in? >> a tightly bound? >> orbit confiscation and just gets "pushed" rather than crushed?"? >>? >> That is something I had never considered. Is it possible that a body? >> like Vesta could "give" or "roll with the punch" and this might? >> mitigate the impact forces as John suggested?? >>? >> Best regards,? >>? >> MikeG? >>? >> -- >> ------------------------------------------------------------------------- --------? >> Galactic Stone & Ironworks - Meteorites & Amber (Michael Gilmer)? >>? >> Website - http://www.galactic-stone.com? >> Facebook - http://tinyurl.com/42h79my? >> News Feed - http://www.galactic-stone.com/rss/126516? >> Twitter - http://twitter.com/galacticstone? >> EOM - http://www.encyclopedia-of-meteorites.com/collection.aspx?id=1564? >> ------------------------------------------------------------------------- --------? >>? >> On 7/22/11, John Lutzon <jl at hc.fdn.com> wrote:? >>>? >>> Hello List,? >>>? >>> I don't know what i don't know---so:? >>> The latest photo of Vesta shows about 1/2 of this protoplanet which is >>> about? >>> 350 miles in diameter? >>> and the largest crater looks approximately 1/10 0f this radius which >>> means? >>> the crater dia. is about 17.5 miles--quite a hit for such a little guy.? >>> I remember seeing a photo of a much smaller asteroid with an impact >>> crater? >>> of? >>> about 1/3 to 1/2 the size of the whole thing and wonder why it wasn't? >>> cracked in half or completely obliterated.? >>>? >>> So, are impact forces mitigated when an object is not in a tightly bound? >>> orbit confiscation and just gets "pushed" rather than crushed?? >>>? >>> John? >>>? >>>? >>>? >>> ----- Original Message -----? >>> From: "brian burrer" <brimane at gmail.com>? >>> To: <meteorite-list at meteoritecentral.com>? >>> Sent: Friday, July 22, 2011 10:57 PM? >>> Subject: [meteorite-list] Is Vesta Mong Nong?? >>>? >>>? >>>> The new photo of Vesta resembles a giant Mong Nong tektite- I did not? >>>> expect to see so many layers.? >>>>? >>>> Happy hunting,? >>>> Brian? >>>> ______________________________________________? >>>> Visit the Archives at? >>>> http://www.meteoritecentral.com/mailing-list-archives.html? >>>> Meteorite-list mailing list? >>>> Meteorite-list at meteoritecentral.com? >>>> http://six.pairlist.net/mailman/listinfo/meteorite-list? >>>>? >>>? >>> ______________________________________________? >>> Visit the Archives at? >>> http://www.meteoritecentral.com/mailing-list-archives.html? >>> Meteorite-list mailing list? >>> Meteorite-list at meteoritecentral.com? >>> http://six.pairlist.net/mailman/listinfo/meteorite-list? >>>? >>? > ? ______________________________________________? Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html? Meteorite-list mailing list? Meteorite-list at meteoritecentral.com? http://six.pairlist.net/mailman/listinfo/meteorite-list? Received on Sun 24 Jul 2011 02:34:39 AM PDT |
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