Finally, humanity gets the tools needed to find life on other planets
Gliese 581d is a potentially habitable planet just 20 light-years away. In 20 years we could know if it delivers on that potential. DarinK/deviantART/CC License
Exactly four centuries ago this year, Galileo sent a letter to the Grand Duchess of Tuscany to implore the powers-that-be of the time to accept the scientific fact that the Earth revolves around the sun and not the reverse.
It was not a new idea — the ancient Greek Aristarchus made the same argument almost 2,000 years earlier, as did Copernicus in the 16th century — but it was Galileo who finally had observations made with the newly invented telescope to prove the case.
Of course, that didn’t save Galileo from persecution and spending the last decade of his life under house arrest, but eventually this fundamental idea became the foundation of astronomy and forever changed our view of the universe and our place in it.
Just as Galileo’s telescope helped prove what had been suspected for centuries, now, exactly 400 years later, many scientists and observers believe a new generation of telescopes — both under construction on Earth and planned for launch into space in the coming years — will bring new discoveries that will again fundamentally alter humanity’s view of our role in the wider cosmos. Specifically, it’s believed these instruments could offer concrete evidence of what many suspect to be near a mathematical certainty: that we are not alone in the universe, that life exists in some form on other distant planets.
“I expect that in the next 10 to 20 years we might be able to determine with the future ground and space telescopes that some exoplanets are likely habitable or even habitable (not just potentially habitable) but not yet to confirm that any is inhabited; that might take longer than 30 years,” Abel Méndez, who directs the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo, told CNET’s Crave blog. “I hope I’m wrong and we do it earlier.”
Méndez, who will appear in a recorded interview on Tuesday’s CraveCast at noon PT, convened some of the smartest people involved in humanity’s exoplanet search effort Monday at an astrobiology conference in Chicago — MIT astrophysicist Sara Seager will be among those attending.
“(We are) embarking on the ‘real search for alien life’ by being the first generation capable of finding signs of life,” Seager said on Twitter last year.
The new capability that Seager is referring to is the next generation of space telescopes that will succeed the likes of the Hubble, Kepler and Spitzer to better identify smaller, Earth-size planets and search for biosignatures emanating from their surfaces or atmospheres. NASA’s James Webb Space Telescope (JWST), with a mirror almost three times larger than Hubble’s, and the Transiting Exoplanet Survey Satellite (TESS) are scheduled for launch in 2018 and 2017, respectively, and will team up to identify and then study potentially habitable or even potentially inhabited exoplanets.
Since the 1990s, there has been a boom in data confirming that our galaxy, our universe and even the unexplored corners of our solar system are utterly littered with planets and other large chunks of rock, some hosting ice, water, lakes, oceans and the building blocks of life.
Most of these discoveries — from the possibly warm “soda ocean” beneath the surface of Saturn’s moon Enceladus to Kepler 186-f, an Earth-size planet in the constellation Cygnus some 500 light-years away that may hold water — have been made with telescopes and technology designed and built pre-Facebook and pre-iPhone. The Hubble space telescope, a veteran workhorse of space exploration, was built in the 1980s.
When it comes to searching the cosmos for signs of life, it’s kind of like we’re living in the age of Google, but still relying on the microfiche machine in the back of the library to help us find what we’re looking for.
“If we want to study (many more) potentially habitable terrestrial planets around nearby stars, there are a couple of things that we need. First, if we plan to observe them with JWST we need to find planets eclipsing bright, nearby, low-mass stars,” Heather Knutson, an assistant professor of planetary science at the California Institute of Technology, told CNET’s Crave blog. “TESS is a crucial step in this process because it will find the closest, brightest transiting planet systems that will make ideal targets for JWST to characterize.”
Astrobiologists won’t look through the JWST and see real-life Wookiees orKlingons waving back at us, but it will allow distant rocky planets and their characteristics to begin to come into focus, in a manner of speaking. Right now, Hubble has a hard time characterizing smaller planets, so this is an important step toward identifying far-off Earth cousins and their characteristics.
The 7 confirmed exoplanets most likely to host life (pictures)8 PHOTOS
The next step to ID’ing E.T., even in microscopic form, would be to get a positive hit for biosignature gases — such as methane, oxygen or carbon dioxide, just to name the familiar ones — from one of these planets.
While Knutson believes “we certainly won’t be able to detect biosignatures” with JWST, Seager is not quite so pessimistic, having said it could be the telescope’s most exciting discovery, but would require good luck.
But we’ve mentioned just two of the planned new telescopes to come in the next decade. NASA’s Wide-Field Infrared Survey Telescope (WFIRST); the European Space Agency’s Gaia (launched 2013) and planned PLATO satellites; new ground-based telescopes in Hawaii, Chile (the Giant Magellan Telescope) and elsewhere, as well as Seager’s own Starshade project, which she explains in the TEDx talk embedded below, will all contribute to the search for distant life over the next 15 years or more.