NASA astronaut Kate Rubins floats in the International Space Station in September 2016, wearing a spacesuit decorated by patients recovering at the MD Anderson Cancer Center. NASA Johnson/Flickr hide caption
International Space Station International Space Station
Trent Barton, a volunteer for the study looking at pressure inside the brain during space flights. Courtesy of David Ham hide caption
SpaceX's Dragon cargo ship is captured by astronauts aboard the International Space Station early Thursday, one day after its initial docking attempt was aborted. AP hide caption
This is what failed to happen on Wednesday morning. In this image from April 17, 2015, a robotic arm on the International Space Station grasps a SpaceX Dragon cargo ship during docking. NASA/AP hide caption
SpaceX's Falcon 9 rocket sits on the launch pad Saturday at Kennedy Space Center in Florida. SpaceX scrubbed the Saturday launch due to a technical issue. The company is tried again — and succeeded — on Sunday. Bruce Weaver/AFP/Getty Images hide caption
SpaceX's Falcon 9 rocket is prepared Friday for a launch at the Kennedy Space Center in Florida. Launch Pad 39A, one of the renovated space shuttle launch pads that SpaceX leases from NASA, has been the site of many of NASA's most famous liftoffs. Bruce Weaver/AFP/Getty Images hide caption
A Russian resupply rocket launched Thursday morning from Kazakhstan. The flight initially went as planned, but the rocket broke up in the atmosphere about six minutes after it took off. NASA TV hide caption
NASA astronaut Shane Kimbrough shows a pouch of turkey he will be preparing for his crew in celebration of the Thanksgiving holiday, aboard the International Space Station. AP hide caption
U.S. astronaut Peggy Whitson gestures before the launch of the Soyuz MS-03 spaceship to the International Space Station on Thursday. Dmitri Lovetsky/AP hide caption
The Soyuz MS-01 spacecraft as it lands with NASA astronaut Kate Rubins, Russian cosmonaut Anatoly Ivanishin and astronaut Takuya Onishi of the Japan Aerospace Exploration Agency on Sunday. Bill Ingalls/NASA hide caption
The Cygnus resupply craft slowly approaches the International Space Station — and its waiting robotic arm, the Canadarm2 — Sunday morning. NASA TV hide caption
Astronaut Kate Rubins and Expedition 48 Cmdr. Jeff Williams speak during an interview aboard the International Space Station last month. NASA via AP hide caption
The SpaceX Falcon 9 and Dragon spacecraft lift off on the CRS-9 mission to bring a new docking adapter and other cargo to the International Space Station. Frank Michaux/NASA hide caption