WASHINGTON – Is there alien life on Mars? Perhaps it already exists on Earth? Or maybe it exists on giant earth-like exoplanets located several light years away?
Scholars from around the world debated such questions Tuesday at the 2017 Astrobiology Science Conference in Mesa, Ariz. There are several significant NASA and private initiatives underway that could provide answers about extraterrestrial life.
Within a year, NASA will begin using its James Webb Space Telescope to look for oxygen and oxygen products in foreign atmospheres on Earth-like exoplanets. The telescope’s first target is the recently discovered Trapist 1, a system made up of seven habitable, Earth-sized planets orbiting a single star. The second target is the LHS 1140B planet, a massive planet that, like Earth, has existing liquid water.
“In essence, we’re looking for planets that are more earthlike that have strong signals on them from photosynthesis, life that covers the surface of the planet. We have the instrumentation in the next few years to observe this, and we already have targets available,” said Victoria Meadows, of the University of Washington. “Oxygen and the James Webb Space Telescope are the reasons why we will find life first on exoplanets.”
Australian National University’s Charley Lineweaver defended the idea that scientists have already discovered alien life, but we’ve ignored it because of our fictional, sometimes fantastic, projections for alien life on television and in the movies. Lineweaver discussed Ilya Prigogine’s far from equilibrium dissipative system, which argues that events like hurricanes, tornados and volcanoes should be considered signs of life. It’s a weird definition, Lineweaver said, that many scientists are uncomfortable supporting, but he argued that we’ve found life in red spots on Jupiter, burning stars and whirlwinds on Mars.
“If you’re willing to make that poetic jump and say that’s what life is, we’ve already found it,” Lineweaver said, adding that if we’re looking for fictionalized versions of alien life in outer space, we’ll never find it.
Another significant research effort is the Breakthrough Listen initiative, a $100 million full-sky survey led by Russian billionaire Yuri Milner and Stephen Hawking. Over the next decade, scientists will use telescopes in West Virginia and Australia to conduct a radio survey of both hemispheres, which has never been done before. Jacob Haqq-Misra, of the Blue Marble Space Institute, said teams will be looking for little laser pulses, among other things, in trying to find communication signals from extraterrestrial civilization.
“You’re going to be hearing about Breakthrough Listen over the next decade, and with any luck, there will be at least some interesting signals to follow up on,” Haqq-Misra said.
Britney Schmidt, of Georgia Tech, believes that scientists will find signs of life on Europa, the innermost moon orbiting Jupiter. The moon has an ice shell that covers up a saltwater ocean that is similar to Earth’s ocean, but has two to three times as much water. Other similarities include a silicate interior, an iron core, an outer silicate mantle and active plate tectonics. NASA is planning two separate missions to help answer questions about Europa: the Europa Clipper and the Europa Lander.
“I think we’ve got a chance in our lifetime to actually be able to land and ask these questions,” Schmidt said.
Svetlana Shkolyar, a Carnegie fellow at Arizona State University, said that finding fossils on Mars first is more likely than finding living forms on foreign planets. Potential answers could come as early as 2020, when two rovers are scheduled to touch down on Mars: NASA’s 2020 Rover and the European Space Agency’s ExoMars Rover. The rovers are designed to fully focus on looking for bio-signatures of life, which has not been a significant focus for previous rovers.
“The momentum is only building, and it’s only going to get more interesting in the next decade,” Shkolyar said.
Sara Walker, with Arizona State University, argued that alien life will be found on Earth. But it won’t be through contact with UFOs; it will be through the discovery of life forms with unknown chemical makeup. She said scientists haven’t found it yet because they’ve been looking for familiar chemical makeup in DNA. She said we need a quantitative theory for life that goes beyond what we already know.
“When we do have such an understanding, the easiest place for us to look will be on Earth, and we already know life happened here once, so why not look to see if it happened again?” she asked.