Less Than 20 Years Until First Contact?

by Nancy Atkinson on November 12, 2008

Allen Telescope Array.  Credit: ATA

Allen Telescope Array. Credit: ATA


The Allen Telescope Array (ATA) has come online with its initial configuration of 42 antennas. The project, led by the SETI Institute, is a non-governmental project funded by Microsoft co-founder Paul Allen in which eventually 350 small radio antennas will scan the sky for signs of extraterrestrial intelligence. To test the system, the ATA sucessfully picked up the New Horizons probe on its way to Pluto. Senior SETI scientist Seth Shostak said at an event in San Francisco Tuesday night that the array could become strong enough by 2025 to look deep enough into space to find extraterrestrial signals. “We’ll find E.T. within two dozen years,” he said.

That’s, of course, assuming the distance we can look into space will be increased with new instruments yet to be built, and that the projected computing power under Moore’s Law actually happens.

Shostak estimated that if the assumptions about computing power and the strength of forthcoming research instruments are correct, we should be able to search as far out as 500 light years into space by 2025, a distance he predicted would be enough–based on scientist Frank Drake’s estimate of there being 10,000 civilizations in our galaxy alone capable of creating radio transmitters–to find evidence of intelligent life that is broadcasting its existence.

Only time will tell.

For the New Horizons observation, made Sept. 10, operators of the ATA used a synthesized beam formed with 11 of the array’s 6.1-meter (20 foot) antennas – a method called “beamforming” that electronically combines the antennas into a single virtual telescope. The 8.4-GHz spacecraft carrier signal was then fed into the SETI Prelude detection system.

“We’re happy to be the ATA’s new friend in the sky, helping SETI to verify the operations of their electronics,” says New Horizons Principal Investigator Alan Stern. “It’s also nice to know that someone else is checking in on us during our long voyage to Pluto and beyond.”

And what does New Horizons look like to the Allen Telescope Array? This plot shows 678 hertz (Hz) of spectrum collected over 98 seconds. The New Horizons signal can be easily seen as a bright diagonal line, drifting at rate of -0.6 > Hz/second.

What New Horizons looks like to The ATA.  Credit: SETI Institute

What New Horizons looks like to The ATA. Credit: SETI Institute

Sources: CNET, New Horizons

Nancy Atkinson is Universe Today's Senior Editor. She also is the host of the NASA Lunar Science Institute podcast and works with the Astronomy Cast and 365 Days of Astronomy podcasts. Nancy is also a NASA/JPL Solar System Ambassador.

  • PB

    To Peter Backus @ the SETI Institute: I am sure the readers here would very much appreciate a response to the comments posted by Chuck Lam and Kay.

  • http://UniverseToday JB

    Better get the “units” right this time! …

    Less than “2 Dozen years” is actually 24 (2 x 12), not “20″ as in the head line. So there’s an extra 4 years to come up with those little green guys!
    Damned imperial-metric conversions :-)

  • AH

    Way to go, Shostak. You just put a 24 year kill-switch on SETI. Prepare to be fired.

  • Andy F

    My view is that there is no harm in trying to detect signals, to answer what must be the greatest of all questions. As Frank Drake recently said, if people are unhappy with the word “science” being attached to the hypothesis (there is after all a problem with falsifiability), then perhaps we should associate it with the word “exploration”.

    I “believe”, (basing my judgement from science/evolution of how life readily developed on Earth, and how the organic building blocks of life are ubiquitous in our solar system and in interstellar space), that the universe is brimming with life.

    Most of this will be microbial/bacterial, but on a small (perhaps very small indeed) fraction of worlds sentient beings will have developed, like us, from these microbes and muck (to quote Sagan), and who knows how thet utilise the RF spectrum or lasers, or their TX powers!

    As a species of wanderers and explorers, despite setbacks, politics and economics, we can never cease either space exploration or ETI searches – it’s part of us, and hence, SETI’s modest cost is well worth it. 24 years may be rather hopeful, but how many of us 6 months ago were actually expecting to see images of exo-planets – some taken from ground-based telescopes? And that’s before we talk about serendipitous discoveries of ETI!

  • http://none Chuck Lam

    To Andy F., I no doubt that most of the population agrees, as I do, with your position on exploration. It just seems to me that SETI is working things backwards. Their effort would be better served promoting the development of hyper-sensitive rf detection equipment capable of sensing femto-watt levels or less of rf from an overwhelming natural background of noise. Currently SETI is looking for the equivalent of a burning candle on the surface of a distant star. Stray rf detection from as little as a few light-years distance simply isn’t going to happen.

  • Ttkk’slklkpaa

    Dear Humans:

    I have found your radio signal but am confused about how to navigate this “internet.” Could someone please direct me to the “website” of your “leader?”

  • Cronos D

    Dear Ttkk’slklkpaa,

    May I be the first to cordially welcome you to our signal! My advice steer clear of ‘sites’ that require a ‘credit card’ & end in .com. Many of them may appear to be our ‘leader’ but in fact only link to information on variations in how our species attempts reproduction but mostly is absolutely incorrect physiologically speaking.

    Maybe for an effective transition to Earth culture monitor our ‘television’ broadcasts and then decide if it may be better to wait until our sun expands into a red giant and life re-emerges on Mars – luck with that!!

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