Martha Chaffee, widow of Roger Chaffee, Sheryl Chaffee, daughter, and Roger Purvenas, son of Sheryl Chaffee, left, along with acting NASA Administrator Robert Lightfoot, right, place wreaths at the graves of Apollo 1 crewmembers Virgil “Gus” Grissom and Roger Chaffee as part of NASA’s Day of Remembrance, Tuesday, Jan. 31, 2017. via NASA http://ift.tt/2jrXp4C

Dione’s lit hemisphere faces away from Cassini’s camera, yet the moon’s darkened surface features are dimly illuminated in this image, due to Saturnshine. via NASA http://ift.tt/2jKX6jK

Astronauts, from the left, Gus Grissom, Ed White II and Roger Chaffee stand near Cape Kennedy’s Launch Complex 34 during training for Apollo 1 in January 1967. via NASA http://ift.tt/2jmBGpA

Uranus’ moon Miranda is shown in a computer-assembled mosaic of images obtained Jan. 24, 1986, by the Voyager 2 spacecraft. Miranda is the innermost and smallest of the five major Uranian satellites, just 480 kilometers (about 300 miles) in diameter. Nine images were combined to obtain this full-disc, south-polar view. via NASA http://ift.tt/2jBNLIN

The JunoCam imager on NASA’s Juno spacecraft snapped this shot of Jupiter’s northern latitudes. via NASA http://ift.tt/2jSCIf5

In a lab at NASA’s Johnson Space Center in Houston, engineers simulated conditions that astronauts in space suits would experience when the Orion spacecraft is vibrating during launch atop the agency’s powerful Space Launch System rocket on its way to deep space destinations. via NASA http://ift.tt/2jmqQmU

The release of the first images today from NOAA’s newest satellite, GOES-16, is the latest step in a new age of weather satellites. This composite color full-disk visible image is from 1:07 p.m. EDT on Jan. 15, 2017, and was created using several of the 16 spectral channels available on the GOES-16 Advanced Baseline Imager (ABI) instrument. via NASA http://ift.tt/2k994lm

The wavemaker moon, Daphnis, is featured in this view, taken as NASA’s Cassini spacecraft made one of its ring-grazing passes over the outer edges of Saturn’s rings on Jan. 16, 2017. via NASA http://ift.tt/2jPxlwA

A grid of small polygons on the Martian rock surface near the right edge of this view may have originated as cracks in drying mud more than 3 billion years ago. via NASA http://ift.tt/2jzvy1d

Expedition 50 Commander Shane Kimbrough of NASA at work outside the International Space Station on Jan. 13, 2017, in a photo taken by fellow spacewalker Thomas Pesquet of ESA. The two astronauts successfully installed three new adapter plates and hooked up electrical connections for three of the six new lithium-ion batteries on the station. via NASA http://ift.tt/2iDoegW