Crew-2 are seen as they prepare to depart for Launch Complex 39A during a dress rehearsal on Sunday, April 18, 2021, at NASA’s Kennedy Space Center. http://www.nasa.gov/sites/default/files/thumbnails/image/51122505089_8c70f66f27_o.jpeg

In this image that astronaut Scott Kelly posted to Twitter on Aug. 9, 2015 during his #YearInSpace captures all the the places humans dwell. http://www.nasa.gov/sites/default/files/thumbnails/image/21226354458_b0fbe5e680_o.jpeg

​Sunset at Gobabeb, Namibia. http://www.nasa.gov/sites/default/files/thumbnails/image/gobabeb_sunset.jpeg

A SpaceX Falcon 9 rocket carrying the company's Crew Dragon spacecraft is seen to the right of the U.S. Capitol Building in Washington as it is launches the Crew-2 mission. http://www.nasa.gov/sites/default/files/thumbnails/image/51134219575_0dd0282491_o.jpeg

Scientists have found fragments of titanium blasting out of a famous supernova. http://www.nasa.gov/sites/default/files/thumbnails/image/casa_crunched_0.jpg

This image from April 24, 2021, shows the SpaceX Crew Dragon Endeavour as it approached the International Space Station. http://www.nasa.gov/sites/default/files/thumbnails/image/iss065e002261.jpg

Astronauts on the space station recently enjoyed a fresh supply of leafy greens, thanks in large part to the efforts of astronaut Michael Hopkins. http://www.nasa.gov/sites/default/files/thumbnails/image/gardener_flower_042721.jpg

After its journey from NASA’s Stennis Space Center aboard the Pegasus barge, the core stage of the Space Launch System (SLS) rocket arrived at the agency’s Kennedy Space Center on April 27, 2021. http://www.nasa.gov/sites/default/files/thumbnails/image/ksc-20210429-ph-jbs01_0007.jpg

The interaction of two doomed stars has created this spectacular ring adorned with bright clumps of gas ­– a diamond necklace of cosmic proportions. http://www.nasa.gov/sites/default/files/thumbnails/image/potw2117a_1.jpg

Swati Mohan is currently the Mars 2020 Guidance, Navigation, and Controls Operations Lead, at NASA's Jet Propulsion Laboratory. http://www.nasa.gov/sites/default/files/thumbnails/image/3479px-nasa_perseverance_rover_landing_day_nhq202102180010.jpeg

On May 5, 1961, NASA astronaut Alan Shepard piloted his Freedom 7 Mercury capsule in a 15-minute suborbital flight, becoming America's first astronaut. In this image, he is shown being hoisted aboard a U.S. Marine helicopter after splashdown. The flight carried him to an altitude of 116 statute miles. http://www.nasa.gov/sites/default/files/images/340806main_GPN-2000-001361_full.jpg

When the the first Star Wars movie was released in 1977, it featured the now-iconic two-sun, “circumbinary” planet Tatooine. http://www.nasa.gov/sites/default/files/thumbnails/image/toi_1338_transit_still.jpg

A U.S. Marine helicopter recovery team hoists astronaut Alan Shepard from his Mercury spacecraft after a successful flight and splashdown in the Atlantic Ocean. http://www.nasa.gov/sites/default/files/thumbnails/image/s88-31386.jpeg

Astronaut and teacher Ricky Arnold is shown on his first spacewalk as a crewmember on STS-119. http://www.nasa.gov/sites/default/files/thumbnails/image/sts-119_eva1_arnold01.jpeg

This detailed image features Abell 3827, a galaxy cluster that offers a wealth of exciting possibilities for study. http://www.nasa.gov/sites/default/files/thumbnails/image/potw2118a.jpg

This June 2020 image from the Hubble Space Telescope shows the galaxy cluster MACS J0416. http://www.nasa.gov/sites/default/files/thumbnails/image/stsci-h-p2034b-m-1786x2000_0.png

OSIRIS-REx bids farewell to Asteroid Bennu and begins its long journey home. http://www.nasa.gov/sites/default/files/thumbnails/image/20210409t142536s732ncml0v008.png

Perseverance entry, descent, and landing lead Allen Chen, gives remarks during a NASA Perseverance rover mission landing update. http://www.nasa.gov/sites/default/files/thumbnails/image/50953499168_e88031c407_o.jpeg

NASA’s X-59 requires the use of creative and strategic supersonic technologies to control and soften the jarring sound as the aircraft flies faster than the speed of sound. http://www.nasa.gov/sites/default/files/thumbnails/image/p21-032-11_3.jpeg

This image taken with the NASA/ESA Hubble Space Telescope showcases the emission nebula NGC 2313. http://www.nasa.gov/sites/default/files/thumbnails/image/potw2119a.jpg