Snapshots from Atlas 5 launch

Eric Boe, one of three astronauts assigned to the first piloted test flight of a Boeing CST-100 Starliner commercial crew ship later this year has been removed from the mission due to unspecified medical issues, NASA announced Tuesday. He will be replaced by veteran astronaut Mike Fincke.

SpaceX Starship is set to propel itself into the record books today on its maiden flight, becoming the tallest, heaviest and most powerful rocket ever launched by humankind into space, topping a role call of famous and history-making heavy-lift launch vehicles including the mighty Saturn 5 that first took humans to the moon.

The 15th resupply mission to the International Space Station by a Cygnus cargo freighter lifted off at 12:36 p.m. EST (1736 GMT) Saturday aboard an Antares rocket from Wallops Island, Virginia. The Northrop Grumman-owned spacecraft is carrying more than 8,000 pounds of experiments and provisions for the space station and its seven-person crew. Capture by the station’s robotic arm occurred at 4:38 a.m. EST (0938 GMT) Monday.