European Space Agency astronaut and current International Space Station Commander Luca Parmitano and ​crewmate Andrew Morgan (out of frame) performed the third spacewalk to repair the Alpha Magnetic Spectrometer. http://www.nasa.gov/sites/default/files/thumbnails/image/iss061e064794.jpeg

Some of the most dramatic events in the universe occur when certain stars die — and explode catastrophically in the process. When these star deaths, or supernovae, occur, their brightness can rival the light of a whole galaxy. The galaxy NGC 5468, shown in this Hubble image, has hosted a number of these supernovae the past 20 years. http://www.nasa.gov/sites/default/files/thumbnails/image/potw1948a.jpg

To make room for the latest cargo craft on Nov. 29, Progress 73 departed the station after undocking from the Pirs docking compartment. http://www.nasa.gov/sites/default/files/thumbnails/image/iss061e063461_0.jpg

Meltwater lakes form on the surface of Greenland’s Petermann Glacier. http://www.nasa.gov/sites/default/files/thumbnails/image/petermann-2019-06-30-crop-legend.png

This image of North and South America at night is a composite assembled from data acquired by the Suomi NPP satellite in April and October 2012. http://www.nasa.gov/sites/default/files/thumbnails/image/city_lights_namerica_8k.jpg

In this image from December 2000, the Expedition One crew--the first to permanently inhabit the International Space Station--are about to eat a treat of fresh oranges. http://www.nasa.gov/sites/default/files/thumbnails/image/iss001-328-015.jpg

​NGC 3175 is located around 50 million light-years away in the constellation of Antlia (the Air Pump). The galaxy can be seen slicing across the frame in this Hubble image, with its mix of bright patches of glowing gas, dark lanes of dust, bright core, and whirling, pinwheeling arms coming together to paint a beautiful celestial scene. http://www.nasa.gov/sites/default/files/thumbnails/image/potw1949a.jpg

As the holiday season approaches, people in the northern hemisphere will gather indoors to stay warm. In keeping with the season, astronomers have studied two groups of galaxies that are rushing together and producing their own warmth. http://www.nasa.gov/sites/default/files/thumbnails/image/ngc6338.jpg

This week in 1999, space shuttle Discovery, mission STS-103, launched from NASA’s Kennedy Space Center on the third Hubble Space Telescope servicing mission. http://www.nasa.gov/sites/default/files/thumbnails/image/sts103-501-026orig.jpg

​This image from the NASA/ESA Hubble Space Telescope shows IC 2051, a galaxy in the southern constellation of Mensa (the Table Mountain) lying about 85 million light-years away. It is a spiral galaxy, as evidenced by its characteristic whirling, pinwheeling arms, and it has a bar of stars slicing through its center. http://www.nasa.gov/sites/default/files/thumbnails/image/potw1950a.jpg

The newly revealed infant stars appear as pink and red specks toward the center and appear to have formed in regularly spaced intervals along linear structures. http://www.nasa.gov/sites/default/files/images/139975main_image_feature_476_ys_full.jpg

The Anti-Atlas Mountains of Morocco formed as a result of the collision of the African and Eurasian tectonic plates about 80 million years ago. http://www.nasa.gov/sites/default/files/thumbnails/image/pia23533.jpg

NASA astronaut Christina Koch makes observations from the International space Station's cupola. http://www.nasa.gov/sites/default/files/thumbnails/image/516b8331.jpg

This loose collections of stars, known as an open star cluster, is image 100 of the Caldwell catalog. http://www.nasa.gov/sites/default/files/thumbnails/image/c100-1.jpg

NGC 4258, a galaxy about 23 million light years away, is the site of impressive, ongoing fireworks. http://www.nasa.gov/sites/default/files/m106.jpg

Stars glitter in the night sky above the Earth's atmospheric glow. http://www.nasa.gov/sites/default/files/thumbnails/image/iss061e110462_large.jpg

This smattering of celestial sequins is a spiral galaxy named NGC 4455, located in the northern constellation of Coma Berenices (Berenice’s Hair). This might sound like an odd name for a constellation — and in fact it is somewhat unusual. It’s the only modern constellation named in honor of a real person from history: Queen Berenice II of Egypt. http://www.nasa.gov/sites/default/files/thumbnails/image/potw1952a.jpg

TOI 700 d is the first Earth-size habitable-zone planet discovered by TESS, NASA's Transiting Exoplanet Survey Satellite. http://www.nasa.gov/sites/default/files/thumbnails/image/pia23408.jpg

This artist’s concept illustrates a catastrophic collision between two rocky exoplanets, turning both into dusty debris. http://www.nasa.gov/sites/default/files/thumbnails/image/bd20307_fnl_lynettecook_0.jpg

NASA welcomed 11 new astronauts to its ranks Friday. http://www.nasa.gov/sites/default/files/thumbnails/image/jsc2020e000612.jpg