Live coverage: SpaceX cargo ship arrives at space station

These photos show the 215-foot-tall Falcon 9 rocket and Crew Dragon spacecraft at launch pad 39A, ready for liftoff from Florida’s Space Coast on a critical test flight to the International Space Station.

SpaceX launched a Falcon 9 rocket Sunday from Cape Canaveral with 143 small satellites, a record number of spacecraft on a single mission, giving a boost to startup space companies and stressing the U.S. military’s tracking network charged with sorting out the locations of all objects in orbit.

The U.S. Space Force expects to complete design validation on SpaceX’s Falcon Heavy rocket by July, ahead of the launch of the military’s first high-priority national security mission on the heavy-lifter late this year.