Day: May 8, 2010

Neanderthal Man is… Us!

NEANDERTALS LIVE! from Assoc. Prof. John Hawks’ weblog.

John Hawks discusses how Neanderthals have survived to the present day, as recently revealed by their sequenced genomes. More interestingly it means the Neanderthals were the same species as Homo sapiens – they really were Homo sapiens neanderthalis, a sub-species variant, as a lot of older paleoanthropologists insisted c.30-40 years ago. We didn’t evolve from them, but they have contributed genes to our common humanity. All us non-Africans, and probably many living Africans, owe them a debt of ancestry. Our expanding population of African-originated variant Homo swallowed up the smaller population of regional variants that was ‘Neanderthal Man’, some 50-40,000 years ago…

DAWN’s slow crawl…

Getting between the planets isn’t easy if you want to stop at multiple destinations on one tank of propellant. Currently the only probe able to do so – unless they do some orbital gymnastics with Cassini – is NASA’s DAWN. Currently DAWN is seemingly within spitting distance (~0.48 AU) of Vesta, its first port-of-call, but both are going too fast to stop. That maneuver is approximately 439 days away according to the count-down clock.

Vesta is an interesting little world – surprisingly an asteroid covered in lava/basalt. Interestingly we already have samples of it available for study, in the form of the HED meteorites, which are the many scattered remains of an immense collision that ripped off a huge chunk of Vestan crust ~1 Gya.

Question: Why did Vesta melt and spew lava, but so many of its asteroidal siblings didn’t too?