Alien hunt in space may score by 2025

The Pittsburgh Post-Gazette ^ | Saturday, October 25, 2003 | Michael Woods

[RadioAstronomer]

And we are deliberately attempting to contact species of life, unknown??

This is not what SETI is attempting at all. There seems to be this misconception that SETI and UFOs go together.

SETI is the hunt for that elusive very narrowband signal that indicates a non-natural emanation. Not unlike what this planet is doing. The rub is where do we look and at what frequency? There seems to be a general consensus that the "waterhole" frequency is the one we should use. Actual Contact? I sure don't see that. It would be terribly difficult if a hello took 2000 years to get there. Waiting for a reply 4000 years in the future would not be very practical.

The other misconception is how to decode the signal. There is no decoding at all (at least for detection). Just the fact of a narrowband carrier is enough to show we are not the only tool building species in this part of the galaxy.

[RightWhale]

Feeling pessimistic about some of the Drake variables lately. Possibility of non-earth intelligent life = 0.000000001 or less. It's all ours.

[RadioAstronomer]

You may be right. I sure hope not.

[GatekeeperBookman]

Thank you for the patient & complete answer-my then 16 yr old resident IT guy had us doing the SETI thing ( back when we were first on line ) & had not really appreciated the facts, as you detail them1 Very nice info!

[RightWhale]

Somebody ought to keep looking anyway. The possibility is not zero, after all.

[RadioAstronomer]

You are most welcome :-)

BTW, to solve the frequency issue, we are looking at millions of frequencies at the same time. Ups the odds a bit. :-)

[RadioAstronomer]

Thanks. :-) Actually SETI is a win win science. If we are alone, this is most profound. If we are not, this is also profound.

[KantianBurke]

We're on an express elevator to hell - going down

[RadioAstronomer]

I liked the first movie much better :-)

[RightWhale]

Either we are alone in the universe or we are not. If we are not alone, there will be some root changes made in most of the non-technical disciplines. If we are alone, most people in the world will have to do a gut check.

[RadioAstronomer]

I agree completely. I also think a gut check would be in order for both possibilities. :-)

[KantianBurke]

[RadioAstronomer]

Yuppers. One of the more nasty SiFi beast on film. :-)

I bought Alien on DVD I liked it so well.

[Ogmios]

How far down and up the band are we looking, are we talking hertz and gigahertz, or somewhere in between, or way above, and below?

[martin_fierro]

I loved parts I & II -- but III & IV SUCKED!

[PatrickHenry]

I would say, based on the success we've had at spotting planets so far, that these three factors:

fp = The fraction of those stars with planetary systems.
ne = The number of planets, per solar system, with an environment suitable for life.
fl = The fraction of suitable planets on which life actually appears.

are very nearly identical in value (although the middle factor may be only 1/2 or 1/3). But this one:

fi = The fraction of life bearing planets on which intelligent life emerges

is where the chances start to drop off significantly.

[Ogmios]

But it leaves us with lots of planets that we might settle.

Now, if we can just figure out a way to get there, economically, feasably, and quickly.

Those are the killers right there.

Lots of space, where do you wish to settle today?

[PatrickHenry]

But it leaves us with lots of planets that we might settle.

Assuming they're not already occupied. Well, that didn't stop Columbus, did it? Perhaps you're right.

[edwin hubble]

"fi = The fraction of life bearing planets on which intelligent life emerges

...is where the chances start to drop off significantly. "


Well, it's looking like life evolved here pretty soon after things cooled below boiling here on Earth.

And stayed at about the same microbial level for two billion years.

Recent conjecture (posted in this forum) speculates that the great Cambrian explosion of life forms could have occured instead a billion or two years earlier. In which case we would be as much as 2 billion years farther in evolution.

Of course, the implication is also there that things would more likely still be at the microbial level today.

Applying this to the 100 million or so sun-like stars...
I agree about variable "fi".

For any one given system with liquid water:
Chance of life = good.
Chance of intelligence = very slim indeed.

Maybe 2 per large spiral galaxy. (We are 1).

[PatrickHenry]

Maybe 2 per large spiral galaxy. (We are 1).

Sagan estimated thousands, and that was before we knew how common planet formation seems to be. But he always was a bit enthusiastic.