TESS's closest approach to Earth, or its perigee, will be 17 Earth radii (about 108,000 km). That's three times higher than the geosynchronous orbit many communications satellites occupy. It's farthest approach, or apogee, is about 59 Earth radii or 376,000 km - just shy of the Moon's average distance of 60 Earth radii. sk yandtelescope.com * M A RCH 2 018 N AS A G O D DA R D S PAC E FLI G HT C E NTE R CREDIT.RIG H T X X X X X X X X X X X X X X X TESS AND EARTH 23http://www.skyandtelescope.com