Life on meteorite ?

[Makandal]

This finally happenned. They did not find vicious shrews nora deadly goat but I think this is a big big progress.
About the Orgueil meteorite, strangely, I read an article in a mythic french magazine of the 60's called Planete about bacteria and other life forms found on this meteorite.
Whatever, this is a great day for humanity.

http://journalofcosmology.com/Life100.html

[DaddyHoggy]

Only had time to skim - but interesting!

[Killer Wolf]

that's way over my head, and i refuse to get excited until we find something that can talk. unless it's an edible arts grduate.

[Sarin]

Quite an interesting thingie...

I've skimmed the article, and to sum it up a bit for those that don't wanna read it...

Study of CI1 carbonaceous chondrites, a rare class of meteorites, mostly those that impacted within last 200 years, revealed so called "strong biomarkers", molecules that appear to be created only via biologic processes, and microstructures in freshly exposed fragments that appear to be fossilized bacteria, apparently similar to Cyanobacteria. Article also provides several arguments why they aren't result of post-impact contamination, notably the nitrogen deprivation. Overall...if these results are confirmed by further research, it would imply existence of life outside our planet.

Sceptic's take: there were previous "findings" of fossilized bacteria in other meteorites, none of those proved to be true...and even if it turned out to be true, actual origin of these meteorites is unknown. During its forming and beginning of life on Earth, our planet underwent quite some cataclysmic changes...it is actually possible that Earth is parent body of these meteorites (gah...wish I was at dorm, got access to some scientific databases there so I could take a look at this).

[Makandal]

Actually, the summary of Sarin is very accurate. In addition to Sarin hypothesis, bacteria have been shown to survive in the higher atmosphere.

These bacteria are already showing some diversity. I am a little afraid that it could be another possibility: what if these meteorites have not been contaminated IN SPACE by earth bacteria. If the Cl1 meteorites are coming from comets, it is very possible these comets skims on the earth higher atmosphere and got loaded with bacteria. Then, these bacteria could have survived and somehow develop when the comet is approaching the sun.

[Killer Wolf]

exactly how high in the atmosphere would they need to be to get sucked up by a comet tho? surely that would hve the comet w/in scarily dangerous proximity to the plant and probably affected by our gravity?
i was under the impression fossils had to be basically buried and exposed to pressure etc, neighter of which i would think could happen on a comet, therefore initially i'd think they'd have to have been formed elsewhere??

[Ganelon]

It's a matter of endless debate, I guess, but I've always figured the universe is big enough that the odds are in favour of there being other life out there somewhere. How advanced and outgoing it might be is yet another debate, but bacteria or something close to them seems logical as one of the forms of life one would find in more places than one would find something more organised and advanced, like weasels, for example. LOL

I would have some concern that it might be something on the order of the Andromeda Strain.

[Sarin]

Actually, the summary of Sarin is very accurate. In addition to Sarin hypothesis, bacteria have been shown to survive in the higher atmosphere.

These bacteria are already showing some diversity. I am a little afraid that it could be another possibility: what if these meteorites have not been contaminated IN SPACE by earth bacteria. If the Cl1 meteorites are coming from comets, it is very possible these comets skims on the earth higher atmosphere and got loaded with bacteria. Then, these bacteria could have survived and somehow develop when the comet is approaching the sun.

Some bacteria can survive in space. It is actually quite likely that Mars has population of Earth bacteria that were brought there by probes. However, getting them into space is very tricky...any object leaving Earth's gravitational field has to reach escape velocity, that is for Earth I think over Mach 5, regardless of mass of object. Very few natural phenomena are capable of this.

[Cody]

To leave Earth, an escape velocity of 11.2 km/s (approx. 40,320 km/h, or 25,000 mph) is required.

[CheeseRedux]

To leave Earth, an escape velocity of 11.2 km/s (approx. 40,320 km/h, or 25,000 mph) is required.

I first memorized this using imperial measurements: 7 miles per second. Although these days 11.2 also resides in memory, 7 is definitely the easier number to remember.

[Cody]

Heh... it was the Saturn V/Apollo launches that drummed that '7' into my brain.

[CheeseRedux]

Saturn V/Apollo launches

I had a slightly different source.

[Cody]

Ah yes... I remember that track well.

[Sarin]

Oh well, I was a little off Anyway, it is unlikely that any natural phenomena could just "launch" anything to orbit, unless it was collision with major celestial body (it is speculated that, when Earth was still mostly molten, it collided with another forming planet, ejecting a part of molten Earth's crust that formed on orbit, thus creating Moon. This however happened before Earth could sustain life, so that's not a way how could life get off Earth) or something like that. And something actually skimming the upper atmosphere and still retain enough velocity to escape...hum, not sure if it is possible due to friction and resulting heating of the object.

[Cody]

Another article on the same subject with a couple of pics.