The telescope that counted new worlds.
In 2006, NASA and its partners launched the Kepler telescope with a goal to try and identify planets in other solar systems. Since then, the telescope found over 2,700 planets orbiting different suns and existing in different solar systems before its retirement in 2018.
For some space enthusiasts, like Jason Steffen, Kepler helped change the way we perceive our universe. Steffen is an associate professor of physics at the University of Nevada, Las Vegas and the author of Hidden in the Heavens: How the Kepler mission’s quest for new planets changed how we view our own.
Steffen said once the Kepler proposal was approved and it was launched, he and his team did not think the telescope would find so many exoplanets in such a short time.
“Kepler was selected right on the heels of the first transiting exoplanet discovery,” Steffen said. “It came to be a time when we really didn't have any idea what we were going to find. We had no idea the extent to which Kepler would be successful at finding exoplanets.”
Kepler’s confirmations of so many exoplanet candidates launched fresh interest in exoplanets. Today, scientists are turning their attention to what the environment of exoplanets and their solar systems are.
“We're turning our attention towards understanding what the properties of the individual stars are, what they're made out of, what their atmospheres are made out of, what the conditions might be on their surface…” Steffen said.
His book Hidden in the Heavens chronicles the Kepler mission’s mark on exoplanet science. Steffen said he hopes those who read his book understand the process of working on the Kepler mission– and the people behind the discoveries.
“A few of the things I think that are interesting is basically giving the reader some insight into how these missions operate, how in the missions are staffed with real people,” Steffen said.
The excitement of finding new worlds
In our own solar system, NASA and other partners are teaming up to search for signs of life on Mars and even on Jupiter’s icy moon Europa. But aside from our own solar system, exoplanets could harbor life billions of miles away.
Although the confirmation of exoplanets occurred just a few decades ago, Eric Perlman, a professor of physics and space sciences at Florida Tech, said the idea of exoplanets and other stars has been hypothesized for centuries.
“It would have been a huge mystery if our planetary system was very rare, because the process that forms planets around stars is the same process that forms the stars themselves,” Perlman said.
As scientists continue to observe exoplanets, the idea that we could find Earth-like worlds is becoming more realistic. Perlman said he believes that we will find life on other planets. One of his favorite exo-solar systems is essentially a condensed version of our own solar system called TRAPPIST.
“The other thing that makes it really fascinating is just how much smaller the scales are,” Perlman said. “TRAPPIST-1 is a much smaller star than our Sun, and all of these planets fit within a radius that is roughly about a 10th of the Earth's distance from the Sun. All of them, all seven.”
For now, exoplanets are only seen as data points. There are no clear pictures of them just yet -- to send missions to observe planets in our solar system or exoplanets will take decades. However, Perlman said there are other ways to study the environment and atmosphere of these other words with spectroscopy studies, a method of determining the makeup of and atmosphere by observing how light interacts with it.
“There are ways that we can find out if there is likely water or oxygen, carbon, whatever else in the atmosphere or on the surface even without going there,” Perlman said. “Nothing will, of course, substitute for going there but that's a much more difficult thing."
