The only telescope array in the world that is focused on the search for extraterrestrial intelligence has produced its first scientific results 鈥� but unfortunately there鈥檚 still no word from ET.
Astronomers hope to continue adding telescopes to the system to search for alien transmissions, but in the meantime, they are also surveying intergalactic space for 鈥榤issing鈥� star-forming gas and other astronomical phenomena.
The project, called the (ATA) after benefactor and Microsoft co-founder , went live in 2007. It was designed to scan for broadcasts from alien civilisations with more consistency and a wider field of view than any previous effort.
Advertisement
Run jointly by the SETI Institute and the University of California, Berkeley, from a site in northern California, the ATA is ultimately intended to comprise 350 dishes. But even with its current complement of 42, it has an impressively wide field of view. It uses relatively small, 6-metre dishes that together can take in five square degrees of sky at a time 鈥� a box as wide as 10 full moons.
鈥淎t any one moment, you look into a very large piece of the sky,鈥� says , director of the . 鈥淎t 350 [telescopes], the ATA just blows any other survey telescope out of the water. Even at 42 it鈥檚 interesting.鈥�
, an ATA team member who presented the project鈥檚 first results at a conference in the Netherlands in June, agrees: 鈥淵ou can see entire galaxies within one shot.鈥�
鈥楳issing鈥� gas
One question the ATA aims to answer is a mystery of missing gas. Star-forming regions don鈥檛 seem to have enough molecular gas to keep up the star-formation rates we observe.
Some researchers think atomic hydrogen might make up the difference. ATA team members have searched for it in four groups of galaxies so far, but have not yet found any new intergalactic gas, deepening the mystery.
鈥淭his paper was our first science paper, so we鈥檝e answered some questions but we鈥檙e finding new questions again,鈥� van Leeuwen says. 鈥淭his paper really shows that our setup is working, we have all the algorithms working, and we could easily upgrade to a more powerful system still.鈥�
Such surveys do not distract from the search for aliens, which 鈥� if they exist and are attempting to communicate 鈥� may send out broadcasts at wavelengths not commonly emitted by astrophysical objects. The ATA can observe a wide range of wavelengths, so it can check stars in the foreground for ETI signals while it watches background galaxies for clouds of atomic hydrogen. The telescope often runs three or four projects in parallel.
鈥淎 telescope like the ATA is just a superb instrument. The fact that it can do astronomical and SETI work at the same time is really just icing on the cake,鈥� Tarter told New 杏吧原创. 鈥淭here鈥檚 no other telescope that can do this.鈥�
Limited funds
But the array is limited in sensitivity and could only detect fainter, more distant objects if it were expanded to include more telescopes, Tarter says. And the funds for that aren鈥檛 in yet.
鈥淲e just submitted last week a proposal to the NSF that would double the size of the ATA if funded,鈥� she says. 鈥淲e have any number of requests out to private donors. We鈥檙e knocking on a lot of doors, but so far they鈥檙e all closed.鈥� The telescopes cost between $150,000 and $250,000 each, depending on how many are built at a time, and filling out the array would cost $40 million, Tarter says.
Until then, Tarter, who recently received a prestigious (Technology, Entertainment, Design) prize, is trying to harness the 鈥渨isdom of the crowds鈥� to optimise the SETI pipeline and analyse the data.
Volunteer scientists
She plans to make the ATA鈥檚 detection algorithms open-source so engineers around the world can help improve them. And she wants to enlist volunteers to study visualisations of the radio data to 鈥渦se their eyeballs as pattern detection devices鈥�.
鈥淲e want to get signals out in front of the world鈥檚 eyes, have people tell us if they see patterns, get a decision about whether there鈥檚 any interesting signal in the data, and get it back to the observatory in time to make changes at the telescope,鈥� she says.
This is an improvement over the distributed computing project because it engages people鈥檚 minds, not just their CPUs, she says.
鈥淲e actually want their 鈥榯hink-ons鈥�, not their electrons,鈥� Tarter says. 鈥淔or me, the reason that that is so necessary is because if you鈥檙e not creatively involved, we can鈥檛 have a conversation about what SETI really means 鈥� I can鈥檛 encourage you to see yourself in a more cosmic perspective unless you鈥檙e actually intellectually involved.鈥�
Journal reference:
