The countdown has begun. The crew is ready. And barring any last-minute hiccups, four astronauts on Wednesday will begin a journey that sends them farther from Earth than any human has gone before.

You’ll want eyes on Jupiter this evening as Europa passes north of Callisto while Ganymede’s large shadow transits the gas giant’s cloud tops. Start observing by 11 P.M. EDT, as the bright planet ...

As the familiar wintertime constellations begin setting earlier each evening, it’s our last chance to catch some of the deep-sky treasures they contain. The constellation Monoceros lies east of better ...

NASA’s Suomi NPP satellite captured this composite image of southern Africa and the surrounding oceans on April 9, 2015. As sea levels in these oceans rise due to climate change, Earth’s rotation ...

From Earth, we only ever see one side of the Moon. This is because the time it takes the Moon to rotate around its own axis happens to be the same amount of time it takes for the Moon to orbit Earth: ...

NASA’s Van Allen Probe A re-entered Earth’s atmosphere on Wednesday, March 11, at 6:37 a.m. EDT, marking the final chapter for a spacecraft that reshaped scientists’ understanding of the radiation ...

Born March 24, 1893, in Germany, Wilhelm Heinrich Walter Baade earned his Ph.D. from the University of Gottingen in 1919. He went on to a career at the Hamburg Observatory, then, in the late 1920s, ...

The Moon passes 4° north of Jupiter at 8 A.M. EDT. By evening, they are high overhead in Gemini the Twins, now nearly 8° apart as the Moon sits near Pollux, the slightly brighter of the two brothers’ ...

In a study published today in Science, researchers say they have solved a climate enigma — the inexplicable surge in global temperature in 2023, rising faster than climate models predicted. By ...

Saturn reaches opposition at 2 A.M. EDT, visible all night and offering stunning views of its rings and moons. The ringed planet now rises around sunset and is highest around local midnight, when it ...

French inventor Louis Daguerre, pioneer of the early photography process of daguerreotypes, is believed to have captured the first photo of the Moon on Jan. 2, 1839. However, the quality and other ...

Visible in Scotland, the total solar eclipse of Aug. 2, 1133, featured nearly 4½ minutes of totality. This eclipse provides just one of many historical examples of people wrongly associating a ...