Astronomers have discovered more than 3700 exoplanets, or planets outside of our solar system, including over 600 multi-planet systems, with another nearly 5,000 candidate dedications awaiting confirmation. These exoplanet discoveries include massive planetssimilar to our Jupiter, smaller Earth-sized planets, and even a solar system home to 7 rocky planets similar in density to Earth, Venus, and Mars.
Many of these discoveries owe thanks to NASA’s Kepler mission and its successor K2, a project surveying our galactic neighborhood for small, Earth-sized planets using a dedicated space-based telescope. NASA’s next major exoplanet hunting effort, called TESS, short for Transiting Exoplanet Survey Satellite, will survey over 200,000 nearby stars and is expected to find thousands of new worlds. TESS is set to launch sometime after April 2018 on the SpaceX Falcon 9 rocket.
So how do astronomers find exoplanets, and how much do we actually know about these worlds outside of our solar system?