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Martin

I remember hearing in a television program on Stephen Hawking that the reason black holes are called black holes is because the physicists who constructed the theory got tired of saying "gravitationally collapsed mass" every other sentence, and this almost certainly accounts for part of the sexiness of black holes. Branding is important, even in science.

Oliver Morton

And branding can backfire -- when Fred Hoyle coined the term "Big Bang" he meant it mockingly as a way of putting down the theory that rivalled his own "steady state" theory. But the big bang stuck.

I seem to remember a story somewhere saying that "black hole" took a little time to catch on in international cosmology circles because its literal translation into Russian is a bit rude...

Bruce Moomaw

I go for "Cold and Damp" as a more plausible view of Noachian Mars (kind of like the wholly erroneous view of California held by the Lady Who's A Tramp).

The absence of any large amounts of water-weathered rocks there -- and the evidence for significant and widely scattered deposits of stuff like olivine, which CAN'T have been exposed to any significant amount of liquid water -- leads me to think that the Warm and Wet enthusiasts have now been firmly disproven. But I still think there's a very strong chance for a Noachian Mars that had small but significant amounts of surface or near-surface liquid water at near-freezing, which (as Phil Christensen tells me) would vastly slow down its weathering tendencies.

James Head has a series of abstracts for the Vernadsky-Brown Microsymposium providing what looks to me like pretty good morphological evidence that water may have run down from the southern hills through the valley networks (probably under an ice crust), trickled into an underground water table in the southern plains, emerged once more onto the surface in channels erupting from the slopes of the North-South Dichotomy, and finally emptied into an ice-shrouded sea filling the northern plains (which may actually have been mostly an ice sheet, with only a thin layer of geothermally warmed liquid water at its base).

A Noachian Mars in which all the surface liquid water was ice-covered is not a very promising locale for the evolution of life, but it isn't an entirely hopeless one either -- especially considering the possibilities of hot springs. But I now have a strong and creepy suspicion that, if we DO ever find proof of either extant or fossil life on Mars, we may always be totally unable to prove that it wasn't just transferred from early Earth to Mars via meteorite, rather than evolving independently on Mars. Now, if we find life on Europa -- THAT'S a different matter...

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