For the first time, a private spacecraft has pushed the International Space Station into a higher orbit without help from a Russian vehicle. Northrop Grumman’s Cygnus uncrewed resupply spacecraft performed the ISS reboost Saturday, before completing its four-month mission on Tuesday.
Over extended periods of time, the ISS–which orbits about 250 miles above Earth–drops slightly towards the atmosphere. To avoid an untimely decommission, the station undergoes periodic boosts from visiting spacecraft—namely, Russia’s Progress. That is, until now.
