Astrobiology tries to determime if life exists elsewhere in the Universe. It tries to do this by searching for what are called "biomarkers". A biomarker is something that is associated with an organism—such as oxygen or methane.
New instruments will be needed to detect biomarkers. These instruments would analyze light coming from Earth-like planets and would determine whether or not there are biomarkers. If a planet is found with biomarkers the next step would be to try to find out what kind of life exists there and to what form it has evolved.
Finally, with the aid of SETI, an effort would be made to determine if the life form developed a high degree of intelligence.—Source: David Morrison’s article "Astrobiology Is the New Modern Framework Encompassing SETI . . . and So Much Else". It appears in the May/June 2006 issue of Skeptical Inquirer.
Bob

Astrobiology

Astrobiology tries to determime if life exists elsewhere in the Universe. It tries to do this by searching for what are called “biomarkers”. A biomarker is something that is associated with an organism—such as oxygen or methane.
New instruments will be needed to detect biomarkers. These instruments would analyze light coming from Earth-like planets and would determine whether or not there are biomarkers. If a planet is found with biomarkers the next step would be to try to find out what kind of life exists there and to what form it has evolved.
Finally, with the aid of SETI, an effort would be made to determine if the life form developed a high degree of intelligence.—Source David Morrison’s article “Astrobiology Is the New Modern Framework Encompassing SETI . . . and So Much Else”. It appears in the May/June 2006 issue of Skeptical Inquirer.
Bob

Re: Astrobiology

[quote author=“Bob”]Astrobiology tries to determime if life exists elsewhere in the Universe. It tries to do this by searching for what are called “biomarkers”. A biomarker is something that is associated with an organism—such as oxygen or methane.

Astronomy and cosmology make such enthralling and beautiful
discoveries, they are fun to follow.  I want to stand up
and cheer for the Mars rovers, even though they’re on such
a deserted planet.

I remember one possible sign of extraterrestrial
life, that bacteria-like fossil found on a
rock thought to be from Mars back in the 90’s.
(e.g. http://newswww.bbc.net.uk/1/hi/sci/tech/1070229.stm )
I thought that was spectacular news at the time, but
its impact on pop culture doesn’t seem to have lasted.
I remember that Pres. Clinton had made an announcement
about the discovery, his announcement was eloquent and
inspiring.  That announcement was in the movie “Contact”
too, but the discovery didn’t echo in pop culture any more
than that.

Astrobiology is very neat stuff, although they may be jumping the gun a bit, since we only know of terrestrial biology so far ...

:wink:

I think the Mars rock will be a question mark until we can actually get to that planet and do some serious searching for other fossils. My understanding, though, is that the initial excitement was pretty well debunked by skeptics, and it stands as “unlikely”, although not impossible.

I enjoyed the papers in SI on the topic. One thing I didn’t notice mentioned is how far away we could expect to pick up actual ET broadcasts if they were like our radio or TV broadcasts. I recall going to a lecture on SETI several years ago and hearing that actually due to attenuation over large distances we couldn’t really expect to pick up TV or radio-type broadcasts over very large interstellar distances. Of course, we can’t listen for them either, since the earth environment is too loud over those frequencies. We would have to put a listening device on the far side of the Moon ...

So, lots of difficulties for SETI generally.

Looking for biomarkers is more potentially fruitful, but how do you tell if the test was successful? Not for awhile, anyhow ...

:?

[quote author=“dougsmith”]Looking for biomarkers is more potentially fruitful, but how do you tell if the test was successful? Not for awhile, anyhow ...

:?

Maybe we should ask the Discovery Institute and William
Dembski if they can detect any irreducibly complex patterns
in the data, sarcastically speaking?  :wink:

I wish you all well.

[quote author=“jump_in_the_pit”]Maybe we should ask the Discovery Institute and William
Dembski if they can detect any irreducibly complex patterns
in the data, sarcastically speaking?  :wink:

In point of fact they have used SETI as an example of just this ... that is, that SETI is looking for examples of “intelligent design”, so “intelligent design” must be scientifically viable.

Which gets everything precisely backwards.

(Looking for ID is fine once you assume that Darwinian evolution gets creatures to the complexity necessary for intelligence ...)

dougsmith - 04 May 2006 06:19 AM

One thing I didn’t notice mentioned is how far away we could expect to pick up actual ET broadcasts if they were like our radio or TV broadcasts. I recall going to a lecture on SETI several years ago and hearing that actually due to attenuation over large distances we couldn’t really expect to pick up TV or radio-type broadcasts over very large interstellar distances. Of course, we can’t listen for them either, since the earth environment is too loud over those frequencies. We would have to put a listening device on the far side of the Moon

wow, thats an interesting point. i never thought about that one. are there any other difficulties you know of? i was just about to read a couple of seth shostak books and I would like to keep them in mind while reading

truthaddict - 14 August 2007 04:31 PM

are there any other difficulties you know of? i was just about to read a couple of seth shostak books and I would like to keep them in mind while reading

I’m sure there are a lot of potential difficulties. The obvious ones, of course, are that:

(1) We have no idea how alien languages might be structured.

(2) We have no idea what sort of alien technologies they would use to communicate.

It’s all guesswork at this point. Listening to talks about this has convinced me that this is well reasoned guesswork ... lots of smart people doing fascinating work. But at the end of the day, it remains guesswork, since we have a sample size of one here.

Shostak is a good guy. Certainly worth reading and listening to, as is his colleague at SETI Jill Tarter. They are well aware of these problems.

I’m sure this has been said by many.  Before searching the galaxy for signs of intelligent life, I think we should first search the earth for signs of intelligent life and possibly try to develop more of it here.

Occam