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Shortbread comets this time

I ran across another off-air comment, this one about the crumbly SW3 comet, which asserted that because it hyped around Sol every 5.4 years (and so — in principle — erodes and decomposes very rapidly), SW3 was “very unlikely” to have lasted as it was for as long as 100,000 years.

I haven’t studied all of the ramifications, but prima facie the commentator appears to be correct.

This will not, however, be a path to communal happiness for the commentator since the orthodox view of comets is that they’ve all been around for roughly as long as the Solar System, a value typically given as roughly [AFAICT, weren’t no stopwatches etc available at the time, whenever it actually was] 4.5 billion years. If he wants his conclusion accepted, the battle is going to be very much 100% uphill — but if successful, SW9 will be very much a shortbread (or shortglow, shortflash — whatever).

There appear to be two more-or-less orthodox schools of thought on these few billion years, one claiming that comets bounce around more or less arbitrarily and another that treats the Oort Cloud as a kind of storage facility for excess comets. According to what I see pro and con, they may each be partially or completely right; sooner or later, some serious little spacecraft are going to buzz through the outer Solar System with their (presumably electronic) eyes wide open, and provide more definite answers.

Comments

Leon RJ Brooks said…
See also the encouraging article referred to by this post, which I dropped into this ’blog a couple of days later.

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