NASA

Nearly 15 years after her first space launch, NASA astronaut Peggy Whitson has now spent more time off-planet than any other American, at more than 534 days. Whitson, 57, is a biochemist who has twice commanded the International Space Station.

SpaceX

SpaceX successfully launched a spy satellite Monday morning aboard a Falcon 9 rocket, the second shot at the launch after cancelling Sunday's original launch.

Updated 7:55 p.m. ET

The most expensive part of doing business in outer space is getting there. The private space flight company SpaceX thinks it can change all that, and Thursday's successful reuse of a rocket was a big test of its business model.

SpaceX launched a communications satellite from the Kennedy Space Center in Florida using a rocket stage that had already been to space and back. SpaceX is betting that this kind of recycling will lower its costs and revolutionize space flight.

ULA Atlas V 421 with NROL-61 satellite
Uninted Launch Alliance

A United Launch Alliance Atlas 5 rocket, designated AV-064, will launch a classified spacecraft payload for the U.S. National Reconnaissance Office. The rocket will fly in the 421 vehicle configuration with a four-meter fairing, two solid rocket boosters and a single-engine Centaur upper stage.

July 28, 2016 | 8:37 am EDT
Cape Canaveral Air Force Station, Space Launch Complex 41

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