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Should SETI Be Looking For Lasers Instead?
colonist writes "Frank Drake, creator of SETI's famous equation, says the detection of extraterrestrial radio signals won't work, because Earth's own radio signal will only be around for 100 years. More and more of Earth's communications use cable and satellites, with no radio-frequency leakage to space. Instead, we should be looking for intentional signals in the form of high-powered lasers that could 'outshine the sun by a factor of 10,000'. Meanwhile, Paul Davies writes that we should be conducting SETI in our DNA. In turns out that an alien message designed to last millenia should be 'inside a large number of self-replicating, self-repairing microscopic machines programmed to multiply and adapt to changing conditions', otherwise known as living cells. Are we the message?"
Are we the message?
I guess that's akin to leaving a flaming bag of poo on the doorstep.
We dump pretty enormous amounts of energy at RADAR wavelengths, 24/7, across the night sky. That'll stop approximately when we have no fear of hostile aircraft showing up at our borders.
You know, never.
--Dan
And exactly since when do satellite uplink transmissions stop at the satellite? The uplink is a radio wave, albeit a directed one. It might still be possible to pick up an alien uplink signal.
"When all you have is a hammer, everything starts to look like a nail"
Next thing you know, we will look for SETI in the burn pattern of a tortilla...or maybe in the reflection from a store window...
Is anyone getting my point here?
"For centuries, mankind has searched for evidence of God, in the skies, in the stars, in animals and in himself." Now do a search and replace s/God/aliens/ and ask if this is really any more a sensible statement. Not to mention, if we do find aliens, are we their peers, or are they our gods?
Final thought of the day...from what I can understand, our solar system is rather young compared to other galaxies out there. And apparently there are hundreds of planets capable of supporting life (our life, that's not even counting life that forms in some environment we consider hostile). Well if that's the case, and life/evolution is as easy as the theories make it sound (all it takes is heat and time)...then why isn't the universe like something out of Star TRek with hundreds of alien species flittering about, dropping in to violate the prime directive, establish moonbases, and so forth? Think about it.
- JoeShmoe
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-- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
A diffuse source contradicts with LASER, but yes, it's possible. But in order for it to be detected over ambient light it would have to be something huge and noticeable like a pulsar - I'd hate to see their electricity bill, these aliens of yours ;)
Sorry buddy. There are a couple of dozen, possibly even hundreds of stars within 25 light years. Alpha Centuari is something like 4.1 lightyears away. So, sun excepted, it takes a hair over 4 years for light from the nearest star to reach us.
Second. What does the difficulty of getting to Saturn have to do with making sense of radio signals?
I think we're really looking in all the wrong places. We're putting human assumptions on alien life.
We assume they would be using radio communication, or that they'd bother with a high-power laser. What if their communication is completely different. Like, something we haven't even considered to be a possibility yet, even in SciFi.. In a transmission media we don't even realize, we may be receiving communications from them, but we simply don't have the equipment to hear it.. We can't even decipher what any other creature on this planet is trying to communicate, why should we even be so egotistical to thing that not only would we know how to receive their communication, but have the vaugest idea of what they're saying.
I thought the idea of SETI was that we'd pick up an omni-directional broadcast, with some alien saying "here we are, can anyone hear me" A laser would be directional. It would have to be intended for Earth, and would need to be tracking many years ahead of where we are. We aren't broadcasting the same signal, why would they? There could be many planets near by with the same idea of listening, but if no one's talking, there's no communcation.
Maybe pulsars aren't just some celestial event, maybe they're beacons, and when we're ready to go to them, we'll find more information. But for now (and the next hundred+ years), we won't be going anywhere near them. Like, we haven't even managed to get a person to the next planet yet. There isn't enough "push" to develop to the next level. Imagine if every country spent their military budget on developing space travel. we'd alerady have a flag on Pluto, along with a bunch of empty beer cans from tourists.
But no, we waste our resources blowing each other up, or making sure we're on the virge of it every day. Remember the cold war? Ya, 40 years of "I'm going to kill you all", just for it to fall apart, and both sides realize that those people we were so scared of for so long aren't really that bad.
I grew up knowing the Soviet Union was the evil Red Army, who had so many weapons pointed at us because they hate us so much. Now, thanks to the fall of the Soviet Union, and the rise of the Internet, I now frequently talk to a Russian, and really, he's a nice guy. I've seen some beautiful pictures around where he lives, where not too long ago I would have believed was a frozen wasteland.
If only all of our governments would give up on this nonsense and cooperate in things, or better yet, ditch the whole "This is ours, you can't play with it" mentality, we'd make a lot more progress.
[rant mode off]
Serious? Seriousness is well above my pay grade.
The question "Are we alone?" is one of the most important philosophical questions; keep in mind that what we call "science" today was once called "pysical science". Philosophy was the profession of scientists centuries ago, and should be part of the toolkit of scientists today.
From a observational standpoint, you have the (yet unproven) theory: There is life outside Earth. In order to try to prove this theory (disproving it is much harder =), you gather data and analyze it. That's generally considered part of science. If for example, Mars missions finds self-replicating life, that can provide an answer to the simpler proposition. The harder one -- intelligent life -- would still need to be shown in some other manner. (Unless we found self-replicating intelligent life on Mars, of course.)
As for the "who cares, I'll be dead by then!" narrow-focused people, keep in mind that the tools and networks being developed for SETI -- massively parallel data set computations -- have usages for other areas of "science" that you would probably consider to be science -- protein folding, for example.
Let's see, you are comparing our solar system to other galaxies? You must realize that the scale of a solar system in relation to the scale of a galaxy is unbelieveably small, right? Ie., there are a (suitably big number) of solar systems in our galaxy alone.
Think of it this way, when you look at a picture of a galaxy, and you see the fuzzy white haze, that haze is (to quote Dr. Sagan) billions and billions of stars.
Now step back, and look at a Hubble Deep Field photo. What do you see? A (suitably large number) of galaxies each of which contains a (suitably large number) of stars/solar systems.
If you really consider the scale of the universe and the scale of time that the universe has been around, it seems pretty obvious that there is a lot of life out there.
The reason we don't have the Star Trek thing going on is that wonderful little thing called "c". That, and I guess they are all trying to learn English...
A house divided against itself cannot stand.
The idea here seems to be that at some point we'll just decide to abandon the whole RF spectrum because we have better mechanisms of comminucating. This is implausible to the point of silliness. We *will* have better mechanisms, but the RF specrum is still there, and still as usable as it ever was, and if no one is using it, why, it will be very cheap. So people *will* use it, of course.
Imagine, for instance, that UHF TV goes away, and non one wants the spectrum any more. Now you can build a local TV system for the cost of a transmitter (which you can get as cheap surplus). So lots of people will do that, so there will be lots of use of the UHF spectrum. It will just be by people doing more interesting thigns than it was before.
More and more of Earth's communications use cable and satellites, with no radio-frequency leakage to space.
Why would there be no radio-frequency leakage to space using satellites? Some of the signal sent down to earth probably bounces back to space. More importantly, most of the radiation beamed up to satellites goes right into space! There's no way those beams are so narrow that they only hit the satellite's receiving antenna...
I've always thought that a Dyson Sphere with "holes" in appropriate places might serve a dual purpose. The first is, of course, a place to live, collect the star's energy, etc...
Secondly, as the sphere rotates around the star the "holes" (notches, spaces, gaps, whatever) would -- from the outside -- appear to be blinking lights. Spaced at prime-number width intervals it'd serve as a nearly eternal beacon for other intelligent life. No maintenance, no machinery, and a broad-spectrum beacon as well.
Get off my lawn.