May 22, 2014
New Projects Look To Ramp Up The Search For Intelligent ETs
Lawrence LeBlond for redOrbit.com - Your Universe Online
The search for extraterrestrial intelligence (SETI) has been a long yet relatively quiet one. First discussed in 1896 when famed inventor Nikola Tesla claimed that his wireless electrical transmission system could potentially be used to contact beings on Mars, scientists have continually developed increasingly sophisticated instruments over the years to reach out to intelligent life in the cosmos.While we know today that there are no intelligent beings living on Mars, this doesn’t stop hunters from looking elsewhere in the galaxy to find someone or something that may be able to communicate with us on some level.
Dan Werthimer, who heads Berkeley’s new SETI Research Center, summarized the current efforts to seek out extraterrestrial intelligent life at a hearing held May 21 at the US House of Representatives’ Committee on Science, Space, and Technology.
At the hearing, Werthimer and astrobiologist Seth Shostak of the SETI Institute in Mountain View, California described the current projects to find intelligent life on other planets and how NASA’s Kepler Space Telescope is contributing to this effort. The duo also reviewed some of the newest projects – eavesdropping SETI – and latest tools – Allen Telescope Array – used in the hunt for intelligent ETs.
“SETI experiments are trying to determine whether other intelligent, technologically capable, life exists in the universe,” Werthimer told the committee, “to answer the question ‘Are we alone?’ or ‘Is anybody out there?’”
These questions may in fact be able to be answered with the innovative tools already in place. The Kepler mission alone has already discovered more than 2,900 exoplanet candidates and more than 960 confirmed exoplanets in more than 76 stellar systems. As well Kepler has shown that the Milky Way Galaxy alone has a trillion planets, three times the number of stars.
“Billions of these planets are Earth sized and in the ‘habitable’ or so called ‘Goldilocks’ zone – not too distant from their host star (too cold), and not too close to their star (too hot). And there are billions of other galaxies outside our Milky Way galaxy – plenty of places where life could emerge and evolve,” Wetrhimer added.
“I hope today’s hearing will enable us to learn more about how research in astrobiology continues to expand this fascinating frontier,” Lamar Smith (R-Texas), committee chairman, said in his opening remarks at the hearing. “The unknown and unexplored areas of space spark human curiosity. Americans and others around the world look up at the stars and wonder if we are alone or is there life on other planets.”
Werthimer has searched extensively for intelligent life in the skies above, relying on UC Berkeley’s long-running SETI experiments and crowd-sourced computing project SETI@home. He has also piggybacked on the Arecibo Telescope in Puerto Rico, the world’s largest radio telescope. Data has continually funneled into SETI@home since 1999, allowing volunteers to use their idle time to search for patterns in ET radio signals that might be an indication of intelligent life.
In a phone conversation with UC Berkeley writer Robert Sanders, Werthimer said that one limitation of merely scanning the sky for signals from ET is that, unless ET is also attempting to signal other intelligent beings, the only signals that may be picked up are those leaked by other sources. On Earth, for example, broadcasts of the TV series I Love Lucy are already reaching the nearest stars, informing any intelligent civilizations that may live there, and are listening, of our existence.
On the other hand, many advanced societies would probably limit such wasted energy, and either send signals via fiber or in tightly focused beams, Werthimer said. If these civilizations colonized other planets, however, they would still need to send signals between planets or use broad beams to track spacecraft.
A new project, called “eavesdropping SETI,” has been unleashed by Werthimer and his colleagues that only listens to two planets in distant systems when they are aligned with Earth, offering the chance to intercept any targeted communications between the two planets.
“The Kepler mission has given us a ton of multiplanet systems to look at,” said Andrew Siemion, a research scientist at the Space Sciences Laboratory who holds joint postdoctoral appointments at ASTRON, the Netherlands Institute for Radio Astronomy, and Radboud University in Nijmegen, the Netherlands.
Werthimer, Siemion and colleagues observed 75 such lineups in 2012 using the Robert C. Byrd Green Bank telescope in West Virginia.
They are now taking this a step farther, planning a broader, and more coordinated effort, dubbed the Panchromatic SETI Project. This project will observe planets around all 30 stars within 13 light years of Earth in the northern hemisphere. The team will do this by harnessing the power of six different ground-based telescopes, including Arecibo, Green Bank and the Keck Observatory in Hawaii. They will search for optical, infrared and radio signals simultaneously and for longer periods of time.
Despite finding “no confirmed exoplanet detections … around any of the stars in our sample,” Siemion said that “statistically speaking, we know that some of these stars should host habitable planets,” and this survey will be the first to put broad multi-wavelength limits on how common technological civilizations are.
“We plan to use every technology we have available to us to look very, very closely at these 30 stars,” he told UC Berkeley.
Werthimer noted that the new research is in danger already as two of the best observatories used by SETI researchers – Arecibo and Green Bank – may be losing federal funding.
“It’s unfortunate that the two largest radio telescopes in the world and that are best for SETI are in danger of closing their doors,” he remarked.