> I am curious as to whether all this hand waving about > CO2 flows may be more about exorcising the ghost of > Percival Lowell rather than describing what actually > is found on Mars.
Sounds less like curiousity and more like trolling to me, but I'm pretty inflammatory myself. [He gobbles the flamebait.] >From what I can tell, Hoffman is just a scientist who saw, dimly, something going on in another science that rung a bell in his mind, and worked toward an interesting hypothesis. I'm sorry if you think that people who help dredge fossil fuels out of the ground can't know much about either fossils or the ground, but I'm inclined to think that they know more than most of us. In any case, the ghost of Lowell could still use some exorcism. Arthur C. Clarke, less than a year ago, said over the wire at some conference that he was sure he saw something in recent surface images, evidence of life gosh darn it. Clarke's a very intelligent and imaginative guy, and a good writer. But please. From distances of even a few inches, some things that look like they are biological are actually mineral, and some things that look mineral in origin are actually biological. Do we really need a superannuated former RAF radar tech telling us what extraterrestrial life does or doesn't look like, from much greater distances? Belief that there's life on Mars is currently faith-based. Belief that there isn't is equally faith-based. Hoffman appears to be a hopeful agnostic on this point. And that stance wins a lot of points with me. -michael turner [EMAIL PROTECTED] > --- Michael Turner <[EMAIL PROTECTED]> wrote: > > > > DS Michaels writes: > > ====== > > Hoffman's general approach on CO2 flows is described > > at > > > http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2002AGUFM.P51B0354H&; > > db_key=AST&high=4061e3e63a18001>> > > > > This paper speaks of catastrophic outflows that can > > produce sudden torrents > > of supercritical CO2 that could, under just the > > right circumstances, produce > > the braided and cut channels we see on Mars. I seen > > nothing whatsoever that > > suggests pools of liquid CO2 could have existed long > > enough to produced > > layer bedrock, salt deposits et al. > > ====== > > > > Hoffman's general approach doesn't include all his > > specific thinking on > > White Mars. I distinctly recall seeing Hoffman > > sketch a scenario of a > > high-density (if short-lived) CO2 atmosphere with > > pressures strong enough to > > keep liquid CO2 bodies on the surface in liquid > > phase. Annoyingly, at the > > moment, his site is down, and I can't find the > > keywords for a Googlecache > > version. I can't speak to the issues of layer > > bedrock or salt deposits. > > Layer bedrock doesn't seem implausible with a liquid > > CO2 surface > > environment, if it lasts long enough. Salt > > deposits? My geochemistry is > > vestigial at best. > > > > Hoffman's main argument rests on the lack of surface > > carbonates, and I > > haven't followed the news from Mars closely enough > > to know whether that > > picture has changed. > > > > BTW, Hoffman has never said that life is so terribly > > unlikely even in a > > White Mars scenario, since subsurface environments > > might be hospitable > > enough. > > > > Nor do I see White Mars in itself being exclusive of > > Warm Wet Mars periods. > > The occasional collision might have released a lot > > of CO2 and particulates, > > warming Mars for relatively short, but formative, > > periods of time, keeping > > H2O in the atmosphere and/or precipitating long > > enough to make a difference. > > We may be looking at a planetary surface in which > > CO2 gas flows AND CO2 > > liquid flows AND H2O liquid flows have all played > > roles at different times. > > After all, it wasn't so long ago that glaciers were > > finally recognized as > > having significantly changed parts of the earth's > > surface. I can't remember > > anyone talking about glacial activity on Mars at > > some point, but why not? > > It takes all kinds (of phases and substances) to > > make a world. And whatever > > Mars is, it's a world - not just a spherical rock > > with some frosting on the > > top and bottom. > > > > Hoffman is a petro guy, he comes late to astronomy > > and planetary studies. > > It's perhaps tempting to take potshots at mainstream > > theory in another > > field, while safely ensconced in your own. On the > > other hand, Alvarez & Son > > came from halfway outside the field of evolution and > > extinction (Luis > > definitely from outside), but now the idea that a > > big collision killed the > > dinosaurs has become the accepted wisdom (even if > > more recently under attack > > again.) > > > > Sometimes the voices from outside are right, or at > > least helpful in breaking > > up theoretical logjams. > > > > -michael turner > > [EMAIL PROTECTED] > > > > > > > > == > > You are subscribed to the Europa Icepick mailing > > list: [EMAIL PROTECTED] > > Project information and list (un)subscribe info: > > http://klx.com/europa/ > > > > > ===== > > Sincerely > > > > James McEnanly > > > __________________________________ > Do you Yahoo!? > Yahoo! Finance Tax Center - File online. File on time. > http://taxes.yahoo.com/filing.html > == > You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] > Project information and list (un)subscribe info: http://klx.com/europa/ > > == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
