A satellite is ejected from the Japan Aerospace Exploration Agency (JAXA) Small Satellite Orbital Deployer on the International Space Station on Dec. 19, 2016. The satellite is actually two small satellites that, once at a safe distance from the station, separated from each other, but were still connected by a 100-meter-long Kevlar tether.
This galaxy acts as an astronomical laser, beaming out microwave emission rather than visible light.
Sunlight truly has come to Saturn's north pole. The whole northern region is bathed in sunlight in this view from late 2016, feeble though the light may be at Saturn's distant domain in the solar system.
Just hours after the winter solstice, a mass of energetic particles from the Sun smashed into the magnetic field around Earth. The strong solar wind stream stirred up a display of northern lights over northern Canada.
Aboard the International Space Station, Expedition 50 Flight Engineer Peggy Whitson of NASA sent holiday greetings and festive imagery from the cupola on Dec. 18.
This image from NASA's Cassini spacecraft is one of the highest-resolution views ever taken of Saturn's moon Pandora. Pandora (84 kilometers, or 52 miles across) orbits Saturn just outside the narrow F ring.