Panspermia, anyone?

[McCoy]

Re: Panspermia, anyone?

 

Maybe this hypothetical stuff floating through space is not life' date=' but some factor that, when it combines with other materials on a world it arrives at, gives rise to life. This would solve the problem of the thing surviving so long in space. Also, it would explain McCoy's point about how we have not been able to replicate life in experiments replicating the Earth's early conditions -- the extraterrestrial X was absent. Also, if we postulate that substance X forms in extraplanetary conditions -- in a nebula, star or whatever -- that would eliminate the problem of how it got off the planet on which it formed in the first place, alleviating part of Kristopher's concerns.[/quote']

Possible.

[McCoy]

Re: Panspermia, anyone?

 

Now' date=' the Galactic Disk is only 10 Gyr old. (The Galaxy is older, but the Disk wasn't formed & stable for some time later.) So, unless V is unreasonably large, even if panspermia actually happens (which certainly is open to question!) [b']panspermia cannot have "colonized" the entire Galaxy yet[/b], even if the incubation time is zero.

 

That also implies that if it does operate, panspermia must have started fairly close to us in the Galaxy, because we know life on Earth was well-established no later than 3.5 Gyr ago (when the disk was only 2/3 its present age) so it had even less time to traverse the Galaxy. That's bordering on an anti-Copernican conclusion, which makes astrophysicists very, very uncomfortable.

Just wanted to thank you again. This is the best arguement against panspermia I've ever read, any chance this could lead to something publishable for you?

[Clonus]

Re: Panspermia, anyone?

 

Maybe this hypothetical stuff floating through space is not life' date=' but some factor that, when it combines with other materials on a world it arrives at, gives rise to life. This would solve the problem of the thing surviving so long in space. Also, it would explain McCoy's point about how we have not been able to replicate life in experiments replicating the Earth's early conditions -- the extraterrestrial X was absent. [/quote']

 

We don't have an entire planet and hundreds of millions of years in which to try out the experiment. (I have an idea for a supers campaign in which the most powerful supers are Blake's mythology, Urizen, Enitharmon and co, who are really aliens who reshaped Earth into a suitable birthplace for life and then accelerated time to see what happened, reducing 2.4 billion years to seven days. They're REALLY powerful.)

[McCoy]

Update

 

So far' date=' all of our attempts to duplicate abiogenesis have failed. Could be one of several possible reasons.

1. We don't fully understand the conditions that existed on early Earth
   
2. There are so many factors that have to be just right that abiogenesis is highly improbable
   
3. There is some factor we are missing in our experiments that should be so obvious we will feel very stupid wehn we do figure it out.
   
4. the conditions were never right for abiogenesis on Earth and life originated elsewhere.
   

I resurect this thread because there has been a breakthrough in abiogenesis. We may have found the missing factor that should have been so obvious. Possibly most of our experiments to date have been too freaking hot!

 

A sealed glass vial containing a mixture of water, amonia, and cyanide, kept in a bath of acetone and dry ice at -108 degrees F (-78 C or 195 K) has yielded seven amino acids and eleven types of nucleobases.

 

Chemical reactions do slow down as the temperature drops, and according to standard calculations, the reactions that assemble cyanide molecules into amino acids and nucleobases should run a hundred thousand times more slowly at -112 defrees F than at room temperature. . .. But strange things happen when you freeze chemicals in ice. Some reactions slow down , but others actually speed up -- especally reactions that involve joining small molecules into larger ones. This seemingly paradox is caused by a process caused by a process eutectic freezing. As an ice crystal forms, it stays pure: Only molecules of water join the growing crystal, while impurities like salt or cyanide are excluded. These impurities become crowded in microscopic pockets within the ice, and this crowding caused the molecules to collide more often.

Other low temperature experiments have yielded such intriguing results as a strand of RNA 30 bases long spontaneously assembling. (The shortest know RNA strand that can act as a catalyst and cause RNA to duplicate itself is 58 bases long.)

 

Check out the February issue of Discover for more on this.

[Vestnik]

Re: Update

 

I resurect this thread

 

McCoy has created life!