Q&A with Keith Gendreau, principal investigator of the first X-ray space communications experiment (members only)

SpaceX test-fired a Falcon 9 rocket at Cape Canaveral Friday evening, igniting nine Merlin engines for several seconds while hold-down restraints kept the launcher on the ground. The company also confirmed the rocket is scheduled for takeoff Wednesday on a space station resupply mission, three days later than previously planned.

Russian ground crews working in starkly different environments on the barren steppes of Kazakhstan and in the lush jungles of South America are readying a pair of Soyuz rockets for two launches Thursday, one to resupply the International Space Station, and another to broaden the capacity of SES’s O3b Internet network.

NASA announced Friday that Rocket Lab will launch a 55-pound CubeSat from Wallops Island, Virginia, toward the moon in early 2021 on a demonstration mission to test lunar navigation techniques and scout a unique elliptical orbit for the planned Gateway mini-space station.