Gullies on Martian sand dunes, like these in Matara Crater, have been very active, with many flows in the last ten years. via NASA https://ift.tt/2GDsf1J

We honor the legacy of Dr. Martin Luther King Jr., who delivered the famous “I’ve been to the mountaintop” speech in Memphis, Tennessee fifty years ago, the day before he was assassinated on April 4, 1968. This image taken from the International Space Station shows a detailed view of the city of Memphis from low-Earth orbit. via NASA https://ift.tt/2q7bgyo

Aeronautical innovations are part of a government-industry partnership to collect data that could make supersonic flight over land possible, dramatically reducing travel time in the United States. via NASA https://ift.tt/2q3irqu

NASA astronaut Drew Feustel seemingly hangs off the International Space Station while conducting a spacewalk on March 29, 2018. via NASA https://ift.tt/2J8uJXz

Before there were computers and software that could stitch together digital images, they were printed on photo paper, trimmed by hand, and taped in place on a large black board. via NASA https://ift.tt/2Gqyvtz

Inside the Astrotech processing facility at Vandenberg Air Force Base, NASA’s Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, or InSight, Mars lander is tested ahead of its scheduled launch on May 5, 2018. via NASA https://ift.tt/2urTvyE

TESS, the Transiting Exoplanet Survey Satellite, is the next step in the search for planets outside of our solar system, including those that could support life. via NASA https://ift.tt/2J1kCU9

This mosaic, taken by the Mars Curiosity rover, looks uphill at Mount Sharp. via NASA https://ift.tt/2pOJ4j9

Claudia Alexander, the project scientist overseeing NASA’s support role in the European Space Agency’s Rosetta mission, stands on the view deck of mission control at the Jet Propulsion Laboratory. via NASA https://ift.tt/2pHX9yJ

An underlying population of infant stars embedded in the nebula NGC 346 are still forming from gravitationally collapsing gas clouds. via NASA http://ift.tt/2pxRyfc