Korean Job Discussion Forums

[huck]

I was just glancing through Bill Bryson's "A Short History of Nearly Everything", and he mentions that quite a few scientists believe that the initial bacteria that kickstarted our planetary evolution probably came from asteroids crashing into the earth.

My question is where do the asteroids come from? They obviously had to have been part of a planet or moon in the past ("Obviously" meaning they had to be cooled and compressed into rock somewhere, right?). So, I assume that most asteroids aren't accelerating through space, so they're probably not traveling too fast. So, where would these asteroids have come from, if they came from a place that had already had plenty of time to let bacteria form? And why would the necessary bacteria be able to form on that planet, but not ours? And how could an asteroid travel that far, with the only means of propulsion being if they somehow touch the gravity of a planet/moon just right and are whipped on past it?

[RACETRAITOR]

It has been fairly well established that bacteria can travel through space on rocks. There is the remote chance that a rock could have travelled from Mars carrying bacteria. It is a long shot though, almost as bad as an old man in a white beard saying "Let there be light."

[dutchy pink]

I think that argument it trying to put a scientific twist on a religious idea, or vice-versa. I forget all the details of it.... But, I think it was Crick who first came up with the idea and called it Hyper Panspermia(?) It was the idea that naked DNA is a somewhat natural product of the universe and is floating around space, sporadically landing on planets which may or may not be hospitable to its nature. He then went on to suggest the idea of Directed Panspermia, which says other life forms intentionally sent DNA out in space to colonize new worlds.
This idea, regardless of its validity, is advocated by a lot of scientist as a way for humans to move forward into the future. As in, we should be actively trying to send our DNA out into the Universe.

As an aside, life arose on Earth pretty early in the grand scheme of things. Most scientist date the origin of the Universe to about 13 Billion years ago. The sort of average age of the oldest stars is 10 billion years. The Sun is a little less than 5 billion years old and Earth, a few 100 million years younger than the Sun. Life on Earth is suspected to have arisen around 4 billion years ago. So from the time the Earth started orbiting the Sun in a relatively stable way, life arose rather quickly.

To me, this somewhat negates the idea of Panspermia, unless it was a coincidence that as as soon as the Earth formed, an Asteroid with DNA hit it.

just my thought

[mindmetoo]

[dutchy pink]

The most engaging book I have read about the evolution of life on earth, from scratch, is Lynn Margoulis and Dorian Sagian, "Micrcosmos- 4 billion years of microbial evolution" It basically lays out her theory of how life could arise on earth, regardless of any imports. She focuses on life from a chemical basis and introduces the idea of symbiosis. It lays the foundation of how a nucleus formed, and the chemical reactions that take place inside a nucleus, and backpeddles to the available chemicals present on earth and what they were doing...

very interesting stuff...

[Cheonmunka]

This is 'astronomy' rather than 'astrology?'

[JMO]

Don't galaxies and solar systems leave a trail of like debris behind them? I thought the idea was that our solar system could have ran through one of those trails and in doing so got bacteria from a different system. Seems pretty far fetched.

[neandergirl]