July 23, 2004 4:56 PM PDT

Intelligent life up there? Wait 20 years

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We should be able to determine whether there is intelligent life in our galaxy in about two decades, thanks to the relentless pace of Moore's Law, a researcher says.

Seth Shostak, the senior astronomer at the Search for Extraterrestrial Intelligence (SETI) Institute in Mountain View, Calif., has calculated that the rate of improvement of radio telescopes will enable astronomers to detect radio signals from other civilizations in the galaxy, assuming that they are out there, by 2025.

"We're not very far from success or not," he said. "This is an experiment that may not be generations away."

The calculation largely comes from the interaction of known quantities about the galaxy, the rate of technological progress, and assumptions about alleged life on other planets.

The galaxy measures approximately 100,000 light years across, Shostak said. Radio telescopes, meanwhile, double in performance approximately every 18 months. This is a result of Moore's Law, which states that the number of transistors on a chip doubles about every 24 months.

As a result of the continuing performance improvement, scientists will be capable of scanning more of our neighborhood in the universe for radio signals--at an increasingly faster rate. Using the needle-in-a-haystack analogy, these two numbers enable scientists to determine the size of the haystack and the rate at which we can sift through the hay.

The unknown question is how many intelligent, radio-transmitting civilizations are out there. Noted Astronomer Frank Drake calculated that about 10,000 could exist in our galaxy. Carl Sagan and others have put that number in the millions.

Using the conservative Drake figures, Shostak estimated that we could come across an alien signal in 2025. Many have said Moore's Law could begin to slow down over the next two decades, but most believe that computing power will continue to progress.

Under Drake's figures, intelligent civilizations should be about 1,000 light years apart, assuming that such civilizations exist.

"It is a prediction based on assumptions," he said. "How many planets like Earth are out there?" But much of SETI's work is largely based on similar assumptions.

Closer to home, the effort will also require funding. The Allen Telescope Array, being partly funded by Microsoft co-founder Paul Allen, will begin to scan the galaxy this fall. It will have 32 antennas. There are plans to expand it to 350 antennas, but that will require about $10 million.

Astra Astronautica plans to publish a full paper on this theory Monday.

6 comments

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If the theory holds true, then
a 350 dish array won't make any difference. We have to assume that the data we are looking for will be as difficult to decompose as 1024 bit encryption.

As a new technological species, we are still far too dependent on logic. An advanced intelligence would have run logic to its reasonable limits and looked for a different model for SpaceTime.

Or to put it more subjectively, we will have to have been broadcasting for at least another 930 years before our signals meet the minimum requirements of a thousand light years, to reach the next most likely destination. Even if we thought we had a coherent signal we would still have to wait 1,000 years for a confirmation, or encryption key.

A species that has been broadcasting for a 1,000 years would have solved most if not all of the rules governing SpaceTime. This means that they would have a common understanding and most of their communications would be inference and implication, as the rules of space are nothing if not immutable.
Posted by (5 comments )
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oops
as the rules of space are nothing if not immutable.

should have read,

as the rules of SpaceTime are nothing if not immutable.
Posted by (5 comments )
Link Flag
We're progressing.
"As a new technological species, we are still far too dependent on logic. An advanced intelligence would have run logic to its reasonable limits and looked for a different model for SpaceTime."

I'd like to point out that, here in the US, we're taking the lead in abandoning logic -- which proves, once again, that we are the natural leaders of civilization. USA! USA! USA!
Posted by nealda (105 comments )
Link Flag
Rules of Space Time?????
Actually, Space Time is already quite well defined. And the
alterrnative to logic is chaos. The time radius limit is a real
problem - a civilization can be gone before the 'I hear You'
message comes in.

ANyhow, the search for intelligent life here on Earth hasn't been
all that successful.
Posted by Earl Benser (4310 comments )
Reply Link Flag
Rules of Space Time?????
Actually, Space Time is already quite well defined. And the
alterrnative to logic is chaos. The time radius limit is a real
problem - a civilization can be gone before the 'I hear You'
message comes in.

Anyhow, the search for intelligent life here on Earth hasn't been
all that successful.
Posted by Earl Benser (4310 comments )
Reply Link Flag
Noise
Any signal we receive will likely be from a civilization several million years more advanced than us. What would it look like? Given the rate of change in compression and encryption in only the last 10 years, we probably could not recognize a signal from another civilization anyway. It would just look like noise to us.
Posted by Jim1900 (821 comments )
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