Photos: Atlas 5 rocket soars from West Coast

SpaceX launched its 16th mission of the year early Monday, lighting up a nighttime sky with a Falcon 9 rocket to deliver a Canadian-owned commercial communications satellite to orbit.

United Launch Alliance called off the planned liftoff of a Delta 4-Heavy rocket and a classified National Reconnaissance Office spy satellite from Vandenberg Air Force Base in California on Wednesday after indications of elevated hydrogen concentrations around one of the launcher’s main engines. Three previous launch attempts were scrubbed by technical concerns and bad weather.

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.