NASA astronauts Joe Acaba (left) and Randy Bresnik (right) at work outside the International Space Station on Oct. 20, 2017, in the third of a series of three planned spacewalks. The two astronauts successfully completed the 6 hour, 49 minute spacewalk at 2:36 p.m. EDT. via NASA http://ift.tt/2zFnj8q

In this June 1973 photo, astronaut Paul J. Weitz, Skylab 2 pilot, mans the control and display console of the Apollo Telescope Mount. Weitz, who also commanded the STS-6 shuttle mission and served as Deputy Director of Johnson Space Center, passed away this week at the age of 85. via NASA http://ift.tt/2z2GxbS

Saturn’s graceful lanes of orbiting ice — its iconic rings — wind their way around the planet to pass beyond the horizon in this view from NASA’s Cassini spacecraft. via NASA http://ift.tt/2xglHRL

This Hubble image shows what happens when two galaxies become one. The twisted cosmic knot seen here is NGC 2623 — or Arp 243 — and is located about 250 million light-years away in the constellation of Cancer (The Crab). via NASA http://ift.tt/2xTIy5i

Jupiter’s moon Amalthea casts a shadow on the gas giant planet in this image captured by NASA’s Juno spacecraft. via NASA http://ift.tt/2yDDMwL

Hidden beneath Chamber A at the Johnson Space Center is an area engineers used to test critical contamination control technology that has helped keep our James Webb Space Telescope clean during cryogenic testing. via NASA http://ift.tt/2gjAzIb

NASA astronaut Joe Acaba photographed Puerto Rico from the cupola of the International Space Station on Oct. 12, 2017. Sharing the image with his followers on social media, he wrote, “Finally a chance to see the beautiful island of Puerto Rico from @Space_Station. Continued thoughts throughout the recovery process.” via NASA http://ift.tt/2gpX41X

This illustration shows the hot, dense, expanding cloud of debris stripped from neutron stars just before they collided. via NASA http://ift.tt/2hK4fP8

NASA astronaut Mark Vande Hei exits the International Space Station on Oct. 10, 2017, for a spacewalk in this photograph taken by fellow spacewalker Randy Bresnik. Bresnik wrote, “A glorious sunrise greeted @Astro_Sabot and I at the start of our 2nd #spacewalk. His visor reflection shows the airlock hatch we came out.” via NASA http://ift.tt/2hExaE6

Dawn bring the sight of Dream Chaser, Sierra Nevada’s reusable spaceplane, as it sits on the runway at NASA’s Armstrong Flight Research Center. via NASA http://ift.tt/2kJGA6h