For decades, the search for life in outer space has focused on finding tiny microbes that would do little to satisfy a growing appetite for connection with beings that more closely resemble us.
It’s been the appetizer to the main course, a search for sophisticated creatures that truly deliver on the answer to one of humanity’s central questions: Are we alone?
Now, thanks to new interest in Congress for further scientific research, NASA is changing its focus to search for life advanced enough to, like us, create technology.
The signs are called technosignatures, as compared with biosignatures, like in microbes, that show signs of life. Technosignatures come primarily as radio signals that allow scientists to infer the existence of technological life in the universe.
A bill proposed in the U.S. House in April recommended that NASA receive $10 million to partner with private sector and philanthropic organizations to search for alien life. It wouldn’t actually allocate the funds, and would still have to pass in the House and Senate, but it represents the first time in 25 years that the federal government has considered using funds to search for extraterrestrial life.
The original program, called SETI, or the search for extraterrestrial intelligence, lost federal funding in 1993 after a year of research didn’t turn up a “single green little fellow,” said then U.S. Sen. Richard Bryan of Nevada.
Unlike SETI, NASA argues that the search for technosignatures goes a step further, focusing on radio or laser emissions, not just communication signals. Our own radio and television broadcasts have been drifting into space, so we may be able to receive signals from other beings, the agency said.
And signs of large structures or an atmosphere full of pollutants — like our own — could prove that there is a civilization like Earth’s elsewhere in the universe.
Whether NASA will find life outside our solar system is anyone’s guess. Astronomer Frank Drake’s Drake formula postulates that there could be 10,000 intelligent civilizations in the galaxy. Italian physicist Enrico Fermi’s Fermi paradox asserts that if there was intelligent life out there, we would have met it already.
But recent discoveries by the Kepler mission of multiple exoplanets, including some that have similarities with Earth, and the TESS mission, which recently launched a satellite that has already found two new exoplanets, have increased public interest in finding alien life.
It’ll have to be more an irregular radio signal to pass the test, though. NASA said that to answer the question of our place in the universe, it will need “unmistakable signs” of life.