“I’m trying to piece together what happened from the videos. First of all, I do not think this is related in any way to the asteroid 2102 DA14! For one thing, this occurred about 16 hours before DA14 passes. At 8 kilometers per second that’s nearly half a million kilometers away from DA14. That puts it on a totally different orbit.”
— Phil Plait, Bad Astronomy, February 15, 2013
Dear Bill:
Its not the time of separation — but the direction and angle — that allows us to distinguish between these objects [DA 2012 and the Russian bolide], correct?
Bill Napier responds regarding the faulty analysis from Phil Plait and his blog: “Bad Astronomy“:
Hi George,
You’re absolutely right. Two objects can be in identical orbits but widely separated. Phil Plait is just plain wrong and I don’t understand how he could have made such an elementary blunder. However, I understand that Don Yeomans (head of NASA’s office of near-Earth objects) has determined that the orbits are in fact quite different.
On the marvelous platinum result, I’m baffled! An iron meteorite is unlikely to fragment Earth-wide, and the lechatelierite which Ted Bunch and colleagues find at widely separated sites can’t be reconciled with this. Also, I’d be looking for big holes in the ground in the neighborhood of these sites. And the time profile of the dust doesn’t fit the idea of a sudden injection and subsequent drift down: the rise should be much sharper. I have no difficulty at all with dust coming in along with a fragment swarm (in fact I would expect it), but I would not expect the Taurid meteors to have a big platinum component.
I wonder if we can be sure that these results will hold up? I recall many years ago speaking to Luis Alvarez about his iridium measurements at the Cretaceous-Tertiary boundary, and an initial problem they had was that the lab assistant had a platinum ring. The tiny erosion involved with the ring was enough to screw up their initial measurements. Having said that, I note that these people come from an impeccable address and are unlikely to make that sort of error. Still, I would personally want to see an independent confirmation before going overboard with this fascinating result.
Best,
Bill Napier
Oops! Need to refine my statement about Phil Plait’s wrongness. The orbits can’t be identical, as I said, but they can be part of a swarm .- Bill