A Kilometer High Cliff on Comet Churyumov – GerasimenkoThis kilometer high cliff occurs on the surface of a comet. It was discovered on the dark nucleus of Comet Churyumov – Gerasimenko (CG) by Rosetta, a robotic spacecraft launched by ESA, which orbited the comet from 2014 to 2016. The ragged cliff, as featured here, was imaged by Rosetta early…Read More

Geminid Meteors over a Snowy ForestMeteors have been flowing out from the constellation Gemini. This was expected, as mid-December is the time of the Geminid Meteor Shower. Pictured here, over two dozen meteors were caught in successively added exposures taken over several hours early Saturday morning from a snowy forest in Poland. The fleeting…Read More

Apollo 17’s MoonshipAwkward and angular looking, Apollo 17’s lunar module Challenger was designed for flight in the near vacuum of space. Digitally enhanced and reprocessed, this picture taken from Apollo 17’s command module America shows Challenger’s ascent stage in lunar orbit. Small reaction control thrusters are at the sides of the moonship…Read More

M51: Tidal Streams and H-alpha CliffsAn intriguing pair of interacting galaxies, M51 is the 51st entry in Charles Messier’s famous catalog. Perhaps the original spiral nebula, the large galaxy with whirlpool-like spiral structure seen nearly face-on is also cataloged as NGC 5194. Its spiral arms and dust lanes sweep in front of its smaller…Read More

Phaethon’s BroodBased on its well-measured orbit, 3200 Phaethon (sounds like FAY-eh-thon) is recognized as the source of the meteoroid stream responsible for the annual Geminid meteor shower. Even though most meteor shower parents are comets, 3200 Phaethon is a known and closely tracked near-Earth asteroid with a 1.4 year orbital period. Rocky and…Read More