Astronomy Picture Of the Day (APOD)The Tails of Comet NEOWISE
Comet NEOWISE (C/2020 F3) is now sweeping through northern skies. Its developing tails stretch some six degrees across this telescopic field of view, recorded from Brno, Czech Republic before daybreak on July 10. Pushed out by the pressure of sunlight itself, the comet's broad, yellowish dust tail is easiest to see.
Comet NEOWISE from the ISS
Rounding the Sun on July 3rd and currently headed for the outer Solar System, Comet NEOWISE (C/2020 F3) has been growing brighter in the predawn skies of planet Earth. From low Earth orbit...
These silvery blue waves washing over a tree-lined horizon in the eastern French Alps are noctilucent clouds. From high in planet Earth's mesosphere, they reflect sunlight in this predawn skyscape taken on July 8. This summer, the night-shining clouds are not new to the northern high-latitudes. Comet NEOWISE is though.
Mercurys Sodium Tail
What is that fuzzy streak extending from Mercury? Long exposures of our Solar System's innermost planet may reveal something unexpected: a tail. Mercury's thin atmosphere contains small amounts of sodium that glow when excited by light from the Sun. Sunlight also liberates these molecules from Mercury's surface and pushes them away.
Comet NEOWISE over Lebanon
A comet has suddenly become visible to the unaided eye. Comet C/2020 F3 (NEOWISE) was discovered in late March and brightened as it reached its closest approach to the Sun, inside the orbit of Mercury, late last week.
M43: Dust, Gas, and Stars in the Orion Nebula
Unspeakable beauty and unimaginable bedlam can be found together in the Orion Nebula Arguably the most famous of all astronomy nebulas, the Great Nebula in Orion is an immense interstellar molecular cloud only 1500 light-years away.
Saturns Northern Hexagon
Why would clouds form a hexagon on Saturn? Nobody is sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System.
Meeting in the Mesosphere
A sensitive video camera on a summit of the Vosges mountains in France captured these surprising fireworks above a distant horizon on June 26. Generated over intense thunderstorms, this one about 260 kilometers away, the brief and mysterious flashes have come to be known as red sprites.
Lynds Dark Nebula 1251
Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away and drifting above the plane of our Milky Way galaxy, the dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region.
The Galaxy, the Planet, and the Apple Tree
The Old Astronomer's Milky Way arcs through this peaceful northern sky. Against faint, diffuse starlight you can follow dark rifts of interstellar dust clouds stretching from the galaxy's core. They lead toward bright star Antares at the right, almost due south above the horizon. The brightest beacon in the twilight is Jupiter, though.