Live coverage: International Space Station crew lands in Kazakhstan

NASA managers Thursday cleared the $1.5 billion Parker Solar Probe for launch early Saturday on a daring mission to “touch the sun,” repeatedly flying through its outer atmosphere to find out why the blazing corona is millions of degrees hotter than our star’s visible surface.

Astronauts Mike Hopkins and Victor Glover floated back outside the International Space Station Monday and completed solar array battery replacement work that began four years ago. They also installed three new video cameras and made preparations for upcoming work to install new roll-out solar blankets to upgrade the lab’s power system.

A small spacecraft built for the Russian military lifted off Thursday on top of a modified Soyuz booster, beginning a mission to reportedly test a compact Earth-imaging platform that could be used on future spy satellites.