Making It Hard For Extraterrestrials To Hear Us

quaith writes "US astronomer Frank Drake has told scientists at a special SETI meeting in London that earthlings are making it less likely that we will be heard in space. In the past, we used huge ground stations to broadcast radio and television signals which could be picked up relatively easily — according to astronomers' calculations anyway. Now we use satellites that transmit at 75 watts and point toward Earth instead of into space. In addition, we've switched to digital which makes the transmissions even fainter. Drake has concluded that very soon, in space no one will hear us at all. I guess we'd better keep listening."

Re:This has its perks

[grouchomarxist]

It would be easier for us to inhabit the Moon or Mars or the oceans or underground or where ever than to go to a new solar system. I imagine that by the time a civilization has the power to go to another solar system for colonization issues of overcrowding would be overcome by technology. If they can get here they'll probably either come for research or just to fuck with us.

Correct me if I'm wrong...

[AnotherUsername]

I was under the impression that historically, our radio and tv signals didn't even make it to Alpha Centauri. Unless we suddenly discover extra-terrestrial life inside of our solar system, does the switch to digital really change anything? Correct me if I am wrong, please.

Re:Not news

[amRadioHed]

The last factor in the equation is L, the length of time a civilization broadcasts radio waves into space.

Re:Not news

[amRadioHed]

Reading the wikipedia page further, it seems like his understanding of L is that it represented how long a technological society would be capable of broadcasting into space. So it seems like he didn't actually consider that as technology advanced civilizations would significantly reduce the amount of stray emissions. As a result his guess for L was around 10000, a few orders of magnitude off it would seem.

Re:Find US?

[pydev]

Has anyone considered the historical evidence of what happens when superior civilizations encounter lesser ones?

That analogy doesn't work. Among other things, aliens can't mate with us and they're probably not going to carry pathogens that can infect us, and those two factors strongly influenced the outcome of European colonization.

(Like Europeans, aliens may be religious nuts bent on destroying our religion and replacing it with their own, but that seems somewhat unlikely.)

Re:Not news

[jibjibjib]

Why do people keep suggesting entanglement as a future communication technology? It doesn't transmit any information. (And if you say "But what if it does and we don't know yet?" then you're not talking about entanglement, you're talking about some random undiscovered physics and using the wrong word for it.)

Re:Not news

[frieko]

Digital wires interfere with each other via RF. There's no way to make a DSP chip complex enough to do digital voice or video without first having a very firm grasp of RF. Meaning "primitive" digital transmissions would be on-off keying at 100 baud or something like that. Which is as detectable from space as AM radio.

Re:Not news

[domatic]

Parent post is making a Star Control 2 reference.