On February 22nd 2017, several scientists made a startling discovery and announcement for all of mankind.
There are not one but seven worlds sighted clustered around a minuscule star in the Aquarius constellation, all having almost the same size to Earth and a warm enough atmosphere making it possible for water and life to exist. The catch?
We need to travel 40 Light Years or 235 Trillion miles to get to the TRAPPIST-1 system. The discovery sparks hope that the hunt for life beyond our own solar system could start sooner than expected.
But when did this undertaking start and how?
“Where is everybody?”
It was the summer of 1950 at the mess hall of the Los Alamos National Laboratory, physicist Enrico Fermi and his colleagues were having a mundane conversation about Earthly matters until Fermi asked a random question, “Where is everybody?” Everyone at the table laughed knowing what he meant.
They knew where Fermi’s question was coming from, because based on statistics, there is a high probability of life on other planets – yet there is no credible evidence other life forms existing. These guys were living at the center of scientific knowledge in the most powerful country on Earth and they never found answers. Fermi knew that statistically they had to exist but wondered why nobody had found one. Years passed and the question has come to be known as “the Fermi paradox”. This curiosity and one question is the fundamental reason for further studies and discoveries that we reap today.
An exoplanet (extrasolar planet) is a planet located outside our solar system that orbits a star. The first scientific discovery was in 1988 however, the first confirmation was made in 1995. Along with the recent discovery of the seven exoplanets, astronomers have identified 3,583 planets in 2,688 planetary systems and 603 multiple planetary systems.
Some of the notable discoveries were 51 Pegasi b, Kepler-186f, PH1b, Gliese 876 b, and a few others including the recent one. Three planets were reported last May 2016, orbiting around TRAPPIST-1. The telescope wasn’t able to see the planets directly but had a record of the shadows they cast.
“This is the most exciting result I have seen in the 14 years of Spitzer operations,” said Sean Carey, manager of NASA’s Spitzer Science Center at Caltech/IPAC in Pasadena, California. “Spitzer will follow up in the fall to further refine our understanding of these planets so that the James Webb Space Telescope can follow up. More observations of the system are sure to reveal more secrets.”
NASA’s Spitzer space telescope observed TRAPPIST-1 (named after the Trappist robotic telescope in Chile’s desert) for 21 days together with data from other observatories it revealed a total of seven planets encircling the star. The planets huddled around an ultra-cool dwarf star TRAPPIST-1 which is 40 light years away. It is slightly larger than Jupiter and shines 2,000 times fainter than our Sun.
“The star is so small and cold that the seven planets are temperate, which means that they could have some liquid water and maybe life, by extension, on the surface,” said astrophysicist Michaël Gillon as reported in Nature.
Discovering seven Earth-like planets circling a star may seem ordinary but “this is really something new,” Ignas Snellen an astrophysicist at Leiden Observatory in Netherlands commented. “When they started this search several years ago, I really thought it was a waste of time. I was very, very wrong.”
Astronomers are now focusing on whether the planets have atmospheres similar to that of Earth. The researchers want to outline the atmosphere of each planet, determine the presence of liquid water on the surface, and search for any signs of life. These are all planned out over the next decade. Any positive results from these could reveal the first hints of life on the surfaces below.
It’s the closest opportunity and the best target to explore life beyond the Milky Way. “Within a decade,” Amaury Triaud of the Institute of Astronomy at Cambridge University said. “I think we’ve made a crucial step in finding out if there’s life out there,” he continued. “If life managed to thrive and releases gasses in a similar way as on Earth, we will know.”
In October 2018, the James Webb Space Telescope will be launched and positioned 1 million miles from Earth. With this, large exoplanets can be observed and starlight filtered through the atmosphere can be detected. It can also aid researchers to conduct atmospheric research and searching for similar star system.
In 2023, the Giant Magellan Telescope, a ground-based observatory is set to start its operation to help figure out more complex and convincing molecular signatures. But there’s a lot that can be done up to now, “We’ll never be 100% sure until we go there,” said Gillon.
The trip itself would take approximately 11,250 years so maybe we’d better off figuring out the undiscovered regions on own planet for now.