NASA astronaut Christina Koch conducts her fourth spacewalk at the International Space Station with fellow NASA astronaut Jessica Meir via NASA https://ift.tt/31uE9V3

In 1572, Danish astronomer Tycho Brahe was among those who noticed a new bright object in the constellation Cassiopeia. via NASA https://ift.tt/31prkLF

NASA astronaut Christina Koch works while tethered near the Port 6 truss segment of the International Space Station. via NASA https://ift.tt/32lR4tR

Amy Ross, a spacesuit engineer at Johnson Space Center, NASA Administrator Jim Bridenstine, watch as Kristine Davis and Dustin Gohmert wear prototype spacesuits. via NASA https://ift.tt/33AwnKU

NASA astronaut Dr. Serena Auñón-Chancellor speaks about her experience on Expeditions 56 and 57 onboard the International Space Station (ISS) at Excel Academy Public Charter School, Monday, June 10, 2019. via NASA https://ift.tt/2B72oy6

NASA astronaut Dr. Serena Auñón-Chancellor speaks about her experience on Expeditions 56 and 57 onboard the International Space Station (ISS) at Excel Academy Public Charter School, Monday, June 10, 2019. via NASA https://ift.tt/328RfZt

NASA’s X-59 QueSST, an experimental piloted aircraft designed to fly faster than sound without producing the annoying – if not alarming – sonic booms of previous supersonic aircraft is taking shape.. via NASA https://ift.tt/2VBLOj9

NASA’s X-59 QueSST, an experimental piloted aircraft designed to fly faster than sound without producing the annoying – if not alarming – sonic booms of previous supersonic aircraft is taking shape.. via NASA https://ift.tt/2p6lcuu

Spitzer Space Telescope’s infrared cameras penetrate much of the dust, revealing the stars of the crowded galactic center region of our Milky Way. via NASA https://ift.tt/2LY3u5o

After completing the first of 10 spacewalks to upgrade the station, astronaut Christina Koch, wrote: The great @Space_Station battery swap series of spacewalks is underway! via NASA https://ift.tt/35f34iE