The ultraviolet universe is invisible from Earth's surface, and most of what we see comes from a single orbiting observatory that may retire in just a few years.
The Hubble Space Telescope remains in good health and may last until the 2030s, but it is gradually being dragged back into Earth's atmosphere. No spacecraft has been able to visit Hubble since 2009, two years before NASA retired its space shuttle fleet. There are early-stage plans to refurbish Hubble again, possibly using a SpaceX Dragon vehicle. But in the meantime, Hubble's eventual retirement could leave behind a big gap.
