Unlike Hubble, which orbits Earth and was visited by NASA astronauts for fixes and upgrades, Webb is going a million miles away to Lagrange Point 2—so Webb almost certainly can’t be fixed if anything goes wrong (though never write-off NASA).

NASA’s $10 billion James Webb Space Telescope (JWST or “Webb” for short) is due to go skywards—at long, long last—on December 18, 2021.