NASA's Kepler space telescope observed over 530,000 stars during its nine-year mission. | Astro4Space

123K views · 2.1K reactions | #OTD in 2009, our Kepler space telescope launched to detect planets outside our solar system. Kepler retired in 2018 and passed its planet-hunting torch to our TESS mission. Keep up with the search for exciting new worlds: https://science.nasa.gov/exoplanets/ | NASA Universe | Facebook