In March 2018, Jack Lissauer of NASA’s Ames Research Center talked about the new phases of NASA’s efforts to identify and research exoplanets. What’s an Exoplanet you ask? Well, it’s a planet that orbits around a star outside of our solar system, much like our Earth does to our Sun. The first phase of this effort started in 2009 when NASA launched the Kepler Spacecraft on a mission to identify Exoplanets. Over the next four years, the Kepler Spacecraft delivered outstanding results by identifying more than 4,000 candidate planets. After detailed investigations, more than 2,000 of these planets were deemed as exoplanets. In 2013, the spacecraft lost two important reaction wheels that control small position adjustments, but it was still able to be repurposed in to see many fields on the sky for short periods of time. This new mission was labeled K2 and the Kepler was able to identify an additional 600 potential exoplanets. Approximately 200 of those planets have been verified. These last 600 planets are closer to the Earth then the previous missions, so it’s possible that one day we might be able to get a closer look! Kepler has done all it can do, so now it’s time to transition to the new phase and launch a planet hunter named TESS.
TESS (Transiting Exoplanet Survey Satellite) will be launched into outer space in 2018. Its primary mission is to survey most of the sky for more exoplanets, but with emphasis on those planets orbiting nearby or around bright host stars. With these criteria, it will make the located planets more suited to follow up observations, such as the characterization of atmospheric compositions and other properties. During the search for exoplanets, more than one third of the planet candidates that were found were associated with target stars. Target stars are only visible every few hours and Kepler was required to continuously monitor them during exploration. When a candidate planet was found around a target star, it was often the case that another candidate planet was found around that same star. These clusters were called “multis” and the scientists discovered that this configuration was quite common and more likely to yield actual planets after research. This large number of “multis” told the scientists that flat multi planet systems like our solar system are common in the universe! With all of these great discoveries made by Kepler and K2, who knows what TESS will come up with!
Lissauer, J. 2018. Transiting Planets from Kepler, K2 & TESS. NASA Technical Reports Server.