'Duck face' selfie in SPAAAACE: Rosetta's snap with bird comet The European Space Agency has maneuvered its Rosetta probe into the perfect position for a selfie with its target – comet 67P/Churyumov-Gerasimenko. Rosetta selfie "Breaker one-nine, this here's the Rubber Duck" (click to enlarge) The image was taken on September 7 using cameras on Rosetta's Philae lander that will …
If that duck is rotating as rapidly as it appears in the shot in the article (about once every 3 seconds)
getting a decent landing and staying there will be quite a trick.
Whatever happens the trip so far is pretty amazing , not to say a great demonstration of astronomical patience.
I take my hat off to the crew at ESA!
I have trouble with the theory that it is made up of two bodies that fused together after a collision. While I see that it is possible, after all with such low gravity the two bodies could have collided with a speed as low as their combined escape velocity that isn't more than walking pace, and a slow one at that. Possible doesn't equal to likely in my humble opinion though. Wouldn't it be far more likely with the somewhat random orbits these things have that any rocks that collided would hit at far greater speeds?
Anybody enlightened out there that could tell me what I am missing?
Oh, and well done ESA for letting Rosetta take part in popular culture and take picture for her snapgram media.
It's possible both bits of rock where ejected after an impact of a much larger body into another larger body, giving them very similar orbits and speed. That would allow then to come together very slowly, possibly after bouncing off each other a few times.
the duck shape is from two roundish objects touching each other with dust and small chunks collected at the "neck." it would have taken a very long time for that whole collection of junk to fully settle into the relatively stable rubble pile it is now. its gravity is so low that if you gave it a swift kick even with your own comparably tiny foot it might break up a bit into a swirl of dust and rocks before gliding back together
"Contact binary, or two-lobed objects, where the lobes are nearly the same size, may also be strengthless. NEA contact binaries may have formed by being spun up, but then failing to form a stable binary system. Few cometary nuclei have been imaged using radar, but several of those also seem to have a contact binary, or two-lobed structure. 103P/Hartley 2, and 8P/Tuttle both have nearly equal lobes joined by a narrow waist [1,2]."
Asteroids, Comets, Meteors Helsinki, 2014
Radar characterization of asteroids and comets
http://www.helsinki.fi/acm2014/pdf-material/Day-2/Session-2/Room-4/HOWELL-23A5.pdf
www.thunderbolts.info
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