Ceres: Life? Pluto: Not So Much

The dwarf planet soap opera continues…

Could the dwarf planet Ceres maintain life? Possibly, says a scientist from a German university. According to new research, this ex-asteroid (who did a deal with the IAU to sell out Pluto, trading in its asteroid status to become a dwarf planet, at the expense of Pluto being demoted from being a planet. Obviously) may have harboured microbial life near geothermal vents in hypothetical liquid oceans (I emphasise hypothetical). Not only that, but Ceres’ chilly microbes could have been kicked into space by meteorites, spreading life throughout the Solar System. Forget Mars (you’re looking too hard), forget Europa (a moon? With life? Pah), the new giver of life could be Ceres, the dwarf planet we know next to nothing about.

Then there’s Pluto. Not much chance of life there either (although it would be fun to speculate, there is methane there after all), but the hard-done-by newly-christened dwarf planet has a rather bizarre atmosphere. Its temperature profile is upside down. Oh, and Pluto has just been reunited with its planetary status… in Illinois only (because a governor really does know more about planets than 400 members of the International Astronomical Union).

Yes, I am very sad that Pluto was demoted in 2006. There, I said it. I’m not sad because there is some scientific heresy going on, I’m sad because I like Pluto and I’d hate to see its status change effect its popularity in any way. It’s a fact of life that things happen we don’t like, and unfortunately, Pluto was caught in the middle of a rather nasty classification battle that the dwarf planet eventually lost. However, Pluto now has its own class of Solar System bodies called Plutoids; a whole subclass of dwarf planets will now bear the proud name of a dwarf planet we know and love. Unfortunately, the Pluto debate rumbles on and I doubt we’ve heard the last of it. Oh well.

One from the loony bin: Illinois now re-recognises Pluto as a planet.

RESOLVED, BY THE SENATE OF THE NINETY-SIXTH GENERAL ASSEMBLY OF THE STATE OF ILLINOIS, that as Pluto passes overhead through Illinois’ night skies, that it be reestablished with full planetary status, and that March 13, 2009 be declared “Pluto Day” in the State of Illinois in honor of the date its discovery was announced in 1930. – yes, really, this is a Senate Resolution. Pluto help us.

How the hell this passed, I have no idea, but I’m thinking the Illinois governor really should be wasting spending his time on writing resolutions about other non-Pluto related resolutions? For more on this, go listen to Phil, he’s as amused about this as I am.

One cool piece of news from the outer reaches of the Kuiper Belt, Pluto’s atmospheric temperature is inverted. This amazing discovery comes from the CRyogenic InfraRed Echelle Spectrograph (CRIRES), attached to ESO’s Very Large Telescope. Measurements have been made of the dwarf planet as it passed in front of distant stars. The star light passes through Pluto’s tenuous atmosphere, revealing that its temperature is in fact cooler near its surface than higher up. This is surprising as usually a planetary surface is heated by the Sun, thus heating the atmosphere closest to it. In the case of Pluto, its surface is composed of ice. The ice sublimes into the lower atmosphere, cooling it down (much like sweat from your skin cools you down).

Also, there’s more methane in Pluto’s atmosphere than previously measured, enhancing the atmospheric temperatures through a weak greenhouse effect. Nobody has mentioned the possibility that this methane may indicate the presence of the “L” word, but give it time.

Going to the smallest dwarf planet, new research suggests that Ceres may have once played host to liquid oceans, possibly spawning life. For the full explanation, check out my article on the Universe Today Life on Ceres: Could the Dwarf Planet be the Root of Panspermia?

Personally, I’m not convinced we can even hypothetically talk about life forming on such a small Solar System body until we are able to study Ceres in-depth. Basically, the work being done by a researcher in Germany suggests that Ceres is a prime candidate as being at the root of the panspermia mechanism. When hit by a meteorite, bits of Ceres broke off, reaching escape velocity fairly easily (as the dwarf planet is low mass), possibly seeding the Solar System with the microbial life that may have developed in liquid oceans of water. But how was the water ever in a liquid state? There is no internal heating mechanism and even when it was forming it is unlikely the dwarf planet would have stayed warm for long (certainly not long enough to support the development of life). There are too many assumptions with this mechanism, and although interesting, I don’t think Ceres will be a serious target for ET hunters any time soon.

In fact, there’s so much going on in the world of dwarf planets, I think I might do a regular column about some of the smallest and most mysterious rocky bodies in the Solar System. This would be especially good as NASA’s Dawn mission approaches the asteroid belt in 2015 to study Ceres a little more intimately. Now that will be exciting…