Why we need a new type of SETI instrument

July 18, 2017
Why we need a new type of SETI instrument
Credit: SETI Institute

Imagine this scenario: On a world orbiting a neighboring star, a society more advanced than our own has used large telescopes to survey all the planets within a few hundred light-years.  In this sample of a million worlds, it finds that one percent show the tell-tale atmospheric gases that indicate life.  One of these is Earth. 

This society is sufficiently distant that clues to the existence of Homo sapiens, in the form of high-powered radio signals, have yet to arrive.  But their scientists know that Earth is laminated with biology of some kind. 

And so, simply as a wake-up call to any intelligence that might be here, they occasionally "ping" Earth with a short flash of – the kind of signal that any technically competent species could recognize as artificial and deliberate.

Such pinprick light flashes could be routinely dotting the heavens today, but we wouldn't know.  Most telescopes are insensitive to short light pulses, and in any case are focused on tiny patches of the sky.  We would no more be aware of such signals than Columbus was of Jupiter's moons, despite the fact that they were in plain sight.

Plain, that is, with the right equipment.

The SETI Institute has developed an instrument that, at relatively low cost, could continuously survey the entire night sky for brief laser pulses.  This is completely unlike the optical SETI efforts that have been made in the past, and continue to be made today: experiments that use sensitive photomultiplier detectors, but are limited to one star system at a time.  That's akin to a radio SETI search able to only monitor a single frequency channel.  Extremely limited.

Credit: SETI Institute

However, the Institute's new Laser SETI instrument is not constrained in this way – it can look everywhere simultaneously.  The technology has been prototyped and subjected to preliminary tests, and consists of a robust assembly of straightforward optical and mechanical components.  It can be easily and inexpensively) replicated.  

A handful of these devices could be used as an observing station with truly all-sky coverage.  By installing such stations at 6 – 8 locations around the globe, both hemispheres of the night sky could be continually monitored.  This is the gold standard for a SETI experiment – all-sky, all the time. 

Laser SETI would cover approximately 200,000 times as much of the heavens as any previous optical SETI effort.  This is not an incremental improvement on current experiments, but a major leap. 

The next step in making this substantial advance is to complete the instrument design, do real-world testing, and then finalize the logistics for manufacture and deployment. 

The possible presence of occasional flashes of light in the sky is both plausible and exciting.  We should look for them.  The Laser SETI campaign will offer us the chance to do so.

Explore further: No extraterrestrial laser pulses detected from KIC 8462852, SETI reports

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6 comments

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rderkis
1 / 5 (3) Jul 18, 2017
We need a new type of SETI alright. One that can't hear and one that can't speak lest we give away our existance. Even just listening could give away our position, using an advanced technology, to somthing we might wish had not detected us.

That money and resources could be used to create fusion, gene editing, and stem cell research. Advancing our civilization.
Osiris1
1 / 5 (2) Jul 19, 2017
Heed the warning of Steven Hawking! Work on fusion first and foremost! Whils solar is sexy a the moment, and does not polllute, it IS static and does not get us off planet as fast as a fusion rocket or thruster. Aneutronic fusion rockets would be used as main lift off engines AND for really great space propulsion because they could accelerate at constant gee force aproaching earth normal and do it for the entire trip. No spinning wheels necessary. we are closer than you realize to doing just this.
Osiris1
2.3 / 5 (3) Jul 19, 2017
Do you live for 400 or over a thousand years? Are you willing to wait for answers for millennia? Are you willing to waste your time on sublightspeed signalling that no advanced culture in the universe with any real intelligence or sense would consider to do? Better way is quantum entanglement signaling. Chinese just used it to communicate with one of their satellites in space. Good property of quantumcomm is that no one ia able to listen to the signal but the sender and receiver......... and THAT is the reason we do not hear from other people in our stellar neighborhood or anywhere else for that matter. They don't do steeenking Einstein speed EM waves!!!!
rderkis
1 / 5 (1) Jul 19, 2017
Do you live for 400 or over a thousand years?

While I agree wholeheartedly with your sentiment, this part is a bad argument.
To answer your question, very soon YES we will live forever,
Ojorf
1 / 5 (1) Jul 19, 2017
Are you willing to waste your time on sublightspeed signalling that no advanced culture in the universe with any real intelligence or sense would consider to do?


Well, it seems we and they have no choice.

Good property of quantumcomm is that no one ia able to listen to the signal but the sender and receiver.........


Sorry not true. Look it up on wikipedia.

They don't do steeenking Einstein speed EM waves!!!!


Sorry, no choice, that's just how fast thing go, can't beat it.
rderkis
not rated yet Jul 19, 2017
Good property of quantumcomm is that no one ia able to listen to the signal but the sender and receiver.


You guys are still talking about today's knowledge and technology.
An advanced civilization will probably consider quantum communications old technology.
BTW The latest theory, not that I understand it, says one particle of the entanglement is affected by the other not across distance but because it in essence knows the future.

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