This image provided by NASA shows astronaut Frank Rubio floating inside the cupola, the International Space Station's "window to the world." Rubio now holds the record for the longest U.S. spaceflight. Rubio surpassed the U.S. record of 355 days on Monday, Sept. 11, 2023, at the International Space Station. He arrived at the outpost last September with two Russians for a routine six months. NASA via AP hide caption
Mission Specialist Sultan Alneyadi of the United Arab Emirates, member of the SpaceX Dragon Crew-6 mission, gestures during the crew walkout from the Neil A. Armstrong Operations and Checkout Building for Launch Complex 39A ahead of their liftoff at NASA's Kennedy Space Center in Cape Canaveral, Fla., on March 1. Jim Watson/AFP via Getty Images hide caption
Orion's maximum distance from Earth was achieved on flight day 13, when it was 268,563 miles away. That's farther than any other spacecraft built for people--but only mannequins were on board. NASA/JSC hide caption
The International Space Station in orbit on May 23, 2011. Paolo Nespoli - ESA/NASA via Getty Images hide caption
Expedition 66 crew members (left to right) Mark Vande Hei of NASA and cosmonauts Anton Shkaplerov and Pyotr Dubrov of Roscosmos are seen inside their Soyuz MS-19 spacecraft after it landed in a remote area near the town of Zhezkazgan on Wednesday in Zhezkazgan, Kazakhstan. Bill Ingalls/NASA/Getty Images hide caption
Russian cosmonauts (from left) Sergey Korsakov, Oleg Artemyev and Denis Matveev wear yellow at the International Space Station. Roscosmos via AP hide caption
Astronaut Ellen Ochoa, STS-110 flight engineer, dons a training version of the full-pressure launch and entry suit prior to a training session at the Johnson Space Center (JSC). Suit technician Andre Denard assists Ochoa. STS-110 took place in April, 2002 and was the 13th shuttle mission to visit the International Space Station (ISS). NASA hide caption
In this image from video provided by NASA, astronauts in the SpaceX Dragon capsule undock from the International Space Station on Monday, Nov. 8, 2021. AP hide caption
A screen image captured at Beijing Aerospace Control Center in Beijing on Saturday shows Chinese astronauts Ye Guangfu (from left), Zhai Zhigang and Wang Yaping waving after entering the Chinese space station. Tian Dingyu/Xinhua via AP hide caption
A U.S. Marines helicopter hovers over the Atlantic ocean during an attempt to retrieve astronaut Gus Grissom's Liberty Bell 7, which sank 15,000 feet shortly after splashdown on July 21, 1961. AP hide caption
Chinese astronauts, from left, Tang Hongbo, Nie Haisheng, and Liu Boming wave as they prepare to board for liftoff Thursday at the Jiuquan Satellite Launch Center in Jiuquan in northwestern China. China plans to launch three astronauts onboard the Shenzhou-12 spaceship who will be the first crew members to live on China's new orbiting space station Tianhe, or Heavenly Harmony. Ng Han Guan/AP hide caption
The International Space Station is larger than a football field. But with 11 people soon to be aboard, there aren't enough places for them all to sleep. Courtesy NASA hide caption
The mouse on the right has been engineered to have four times the muscle mass of a normal lab mouse. A drug to achieve the same effect was recently tested in space. Se-Jin Lee/PLOS One hide caption
An arist's depiction of SpaceX's Crew Dragon, which is set to take NASA astronauts to the International Space Station May 27. SpaceX hide caption
The astronauts of Apollo 11 train in various simulations. NASA hide caption
Astronaut Alan L. Bean holds a container filled with lunar soil collected during the extravehicular activity in which astronauts Charles Conrad Jr., commander, and Bean, lunar module pilot, participated. Charles Conrad Jr./NASA hide caption
NASA has named nine astronauts to crew the first test flights and missions of Boeing's CST-100 Starliner and SpaceX's Crew Dragon capsule. From left to right: Sunita Williams, Josh Cassada, Eric Boe, Nicole Mann, Christopher Ferguson, Douglas Hurley, Robert Behnken, Michael Hopkins and Victor Glover. NASA hide caption
Crew members on one of the simulated Mars missions this spring included Pitchayapa Jingjit (from left), Becky Parker, Elijah Espinoza and Esteban Ramirez. Community college students and teachers in real life, the team members spent a week in the Utah desert, partly to experience the isolation and challenges of a real trip to Mars. Rae Ellen Bichell/NPR hide caption
NASA's 2017 astronaut candidates round up for a group photo on Tuesday at Ellington Field near Johnson Space Center. The 12 pictured are, front row, left to right, Zena Cardman, Jasmin Moghbeli, Robb Kulin, Jessica Watkins, Loral O'Hara; back row, left to right, Jonny Kim, Frank Rubio, Matthew Dominick, Warren Hoburg, Kayla Barron, Bob Hines and Raja Chari. NASA hide caption
Trent Barton, a volunteer for the study looking at pressure inside the brain during space flights. Courtesy of David Ham hide caption