Famed astronomer Carl Sagan once said “The universe is a pretty big place. If it’s just us, seems like an awful waste of space.” UCSB physics professor Philip Lubin shares the same sentiment.
There are estimated to be more than 100 billion stars in our galaxy alone, and our search strategy so far has been “woefully inadequate,” according to Lubin.
“With a telescope of diameter 10 cm and survey time of three years, we should be able to find with a 100 percent certainty, any signal in our galaxy,” Lubin said.
Our knowledge of life on planets is of the order of 10-20, and this number can be greatly expanded with remote sensing. Assuming there are life forms out there with similar or more advanced technological levels, we should be able to detect their presence with fairly basic equipment.
As the leader of the Experimental Cosmology Group, Lubin said the search for extraterrestrial intelligence (SETI) is increasingly possible and accurate with the tools available today. The search is by no means a small feat, but scientists are observing it at a higher frequency than they once did.
One thing we are not doing, however, is broadcasting our own signal, even though we are capable of doing so. “I believe we should be transmitting our information to the universe, it’s foolish not to,” Lubin said. “We have been trained as children to fear the dark. We fear the unknown.”
Since the advent of radio communications and television, we have technically been broadcasting our location. However, since these communications only came about 50-60 years ago, our ‘signal’ has only been broadcast 50-60 light years away, which is not far in a universe that is 13.8 billion light years across.
In a paper published by Lubin, he explains that extraterrestrial life can be observed to the order of 1012 and possibly even 1020 systems. UCSB is discussing a measurement strategy with La Cumbres Observatory Global Telescope Network (LCOGT) to use their station at Sedgwick Ranch for this search.
“We have evolved very rapidly technologically in the last 50 years,” Lubin said. In his research, Lubin assumes that if a hypothetical intelligent species exists, they have a level of technology compared to that we have already achieved.
One of the enabling technologies of SETI is the recent dramatic progress in solid state lasers and laser amplifiers that can be combined together to form larger lasers to increase our own visibility. Using many smaller systems together to form large arrays allows for free space beam combining with no upper limit to power.
“We have never been in such a technological state … and hence it is logical to explore its ramifications in many areas, SETI being one of them,” Lubin said. “All such remote sensing searches require us to make assumptions that may have no basis in reality … but it is all we have to go on and hence it should be pursued consistent with reasonable levels of effort.”
The search for intelligent life outside earth has always been a high-risk, high reward notion and still is. A detection would no doubt forever change humanity, but for the better or worse our fear of the unknown, as Lubin puts it, holds us back from reaching out ourselves.
A version of this story appeared on p.14 of the Thursday, May 26, 2016 print edition of the Daily Nexus.