way back in 2013 nasa chose tess as one of its future missions and it was originally pegged to launch last year. that launch will finally happen today with liftoff set for 6:32 p.m. edt from space launch complex 40 at cape canaveral air force station. the prediction is 80% for favorable weather for liftoff.nasa tv will televise the launch from 6 to 8 p.m. live. if you aren’t familiar with tess, or transiting exoplanet survey satellite, it’s goal over the next two years is to conduct scans on 200,000 of the brightest stars near our solar system. the goal is to look for dips in the brightness of the stars that indicate orbiting planets.those dips in brightness are known as transit. nasa thinks that tess will discover 20,000 exoplanets with over 50 of them being earth-sized planets. nasa also predicts the discovery of up to 500 planets that are less than twice the size of earth.tess is a follow up to the kepler spacecraft that was launched back in 2009 with a goal of finding exoplanets. kepler is nearly out of fuel and was predicted to run out of fuel in months about a month ago.nasa noted that while tess will use the same method as kepler to find planets, it will observe stars that are 30-100 times brighter and ten times closer that the stars kepler focused on. scientists believe that some of the discovered planets might be close enough to view with telescopes.source: nasa