Live coverage: Kennedy Space Center to reopen Friday

Boeing and SpaceX hope to launch commercial crew ferry ships on long-awaited test flights later this year, but both companies face major challenges getting the spacecraft certified before late 2019 when seats aboard Russian Soyuz spacecraft will no longer be easily available for NASA space station crews, officials told lawmakers Wednesday.

The sampling mechanism on NASA’s OSIRIS-REx spacecraft is stuffed with specimens captured from asteroid Bennu earlier this week — so full that some of the rocks are floating out into space. Officials said Friday they will stow the samples inside the mission’s Earth return capsule sooner than planned to minimize the loss of asteroid material.

A team of SpaceX engineers is building a prototype of the spaceship Elon Musk hopes will one day carry people and cargo deep into the solar system, and it could begin low-altitude testing next year, kicking off a multi-step test campaign before eventually going into space, then perhaps the moon or Mars.