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. http://www.nasa.gov/sites/default/files/thumbnails/image/nithin_mac_panel_0.jpg

Jupiter’s moon Amalthea casts a shadow on the gas giant planet in this image captured by NASA’s Juno spacecraft. http://www.nasa.gov/sites/default/files/thumbnails/image/pia21969.png

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). http://www.nasa.gov/sites/default/files/thumbnails/image/potw1742a.jpg

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. http://www.nasa.gov/sites/default/files/thumbnails/image/pia21352-1041.jpg

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. http://www.nasa.gov/sites/default/files/thumbnails/image/sl2-x9-747.jpg

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. http://www.nasa.gov/sites/default/files/thumbnails/image/iss053e119677.jpg

At NASA's Kennedy Space Center, organisms in a Petri plate are exposed to blue excitation lighting in a Spectrum prototype unit. NASA scientists and engineers are developing experiments to determine how different organisms, such as plants, microbes or worms, develop under conditions of microgravity. http://www.nasa.gov/sites/default/files/thumbnails/image/ksc-20171016-ph_csh01_0005_0.jpg

This Hubble infrared image is part of an observing program that imaged 41 massive galaxy clusters to find the brightest distant galaxies for theJames Webb Space Telescope to study. http://www.nasa.gov/sites/default/files/thumbnails/image/potw1743a.jpg

Flying hundreds miles above, astronauts aboard the International Space Station photographed Lake Hazlett and Lake Willis in Western Australia's Great Sandy Desert. Hundreds of ephemeral salt lakes are peppered throughout the arid Australian Outback. http://www.nasa.gov/sites/default/files/thumbnails/image/iss052-e-20826_lrg.jpg

Canadian Space Agency astronaut Jeremy Hansen is suspended over a mock-up of the International Space Station during a microgravity simulation. http://www.nasa.gov/sites/default/files/thumbnails/image/jsc2017e127993.jpg

This sequence of images shows the Sun from its surface to its upper atmosphere all taken at about the same time on Oct. 27, 2017. http://www.nasa.gov/sites/default/files/thumbnails/image/pia22055.jpg

This false-color image demonstrates how use of special filters available on the Curiosity Mars rover's Mast Camera (Mastcam) can reveal the presence of certain minerals in target rocks. T http://www.nasa.gov/sites/default/files/thumbnails/image/pia22066_0.jpg

NASA is performing a series of tests to evaluate how astronauts and ground crew involved in final preparations before Orion missions will quickly get out of the spacecraft, if an emergency were to occur on the pad prior to launch. http://www.nasa.gov/sites/default/files/thumbnails/image/38093765071_045d50699f_o.jpg

As Cassini hurtled toward its fatal encounter with Saturn, the spacecraft turned to catch this final look at Saturn's moon Pandora next to the thin line of the F ring. http://www.nasa.gov/sites/default/files/thumbnails/image/pia21355-1041.jpg

NASA's Solar Dynamics Observatory came across an oddity that the spacecraft has rarely observed before: a dark filament encircling an active region (Oct. 29-31, 2017). Solar filaments are clouds of charged particles that float above the sun, tethered to it by magnetic forces. http://www.nasa.gov/sites/default/files/thumbnails/image/pia22104.jpg

On November 9, 1969, the uncrewed Apollo 4 test flight made a great ellipse around Earth as a test of the translunar motors and of the high speed entry required of a crewed flight returning from the Moon. http://www.nasa.gov/sites/default/files/thumbnails/image/as4-01-580.jpg

The Orbital ATK Antares rocket, with the Cygnus spacecraft onboard, launches from Pad-0A, Sunday, Nov. 12, 2017 http://www.nasa.gov/sites/default/files/thumbnails/image/38332007302_cc4875c5bf_o.jpg

Can you identify this river? http://www.nasa.gov/sites/default/files/thumbnails/image/amazon.jpg

On November 14, 1971, Mariner ( took this image of a shield volcano on Mars. http://www.nasa.gov/sites/default/files/thumbnails/image/7651156028_f41dfff15c_o.jpg

How can you see the atmosphere? The answer is blowing in the wind. http://www.nasa.gov/sites/default/files/thumbnails/image/12772_hurricanes_and_aerosols_youtube_1080.jpg