Astronomy Picture Of the Day (APOD)Crescent Enceladus
Peering from the shadows, the Saturn-facing hemisphere of tantalizing inner moon Enceladus poses in this Cassini spacecraft image. North is up in the dramatic scene captured during November 2016 as Cassini's camera was pointed in a nearly sunward direction about 130,000 kilometers from the moon's bright crescent.
Asteroid 319 Leona cast a shadow across planet Earth on December 12, as it passed in front of bright star Betelgeuse. But to see everyone's favorite red giant star fade this time...
Supernova Remnant Cassiopeia A
Massive stars in our Milky Way Galaxy live spectacular lives. Collapsing from vast cosmic clouds, their nuclear furnaces ignite and create heavy elements in their cores. After only a few million years for the most massive stars, the enriched material is blasted back into interstellar space where star formation can begin anew.
APOD: 2023 December 13 Б Deep Field: The Heart Nebula
What excites the Heart Nebula? First, the large emission nebula on the left, catalogued as IC 1805, looks somewhat like a human heart. The nebula glows brightly in red light emitted by its most prominent element, hydrogen, but this long-exposure image was also blended with light emitted by silicon (yellow) and oxygen (blue).
APOD: 2023 December 12 Б Aurora and Milky Way over Norway
What are these two giant arches across the sky? Perhaps the more familiar one, on the left, is the central band of our Milky Way Galaxy. This grand disk of stars and nebulas here appears to encircle much of the southern sky.
APOD: 2023 December 11 Б Solar Minimum versus Solar Maximum
The surface of our Sun is constantly changing. Some years it is quiet, showing relatively few sunspots and active regions. Other years it is churning, showing many sunspots and throwing frequent Coronal Mass Ejections (CMEs) and flares.
APOD: 2023 December 10 Б Big Dipper over Pyramid Mountain
When did you first learn to identify this group of stars? Although they are familiar to many people around the world, different cultures have associated this asterism with different icons and folklore. Known...
Pic du Pleiades
Near dawn on November 19 the Pleiades stood in still dark skies over the French Pyrenees. But just before sunrise a serendipitous moment was captured in this single 3 second exposure; a bright meteor streak appeared to pierce the heart of the galactic star cluster.
Vega and Comet 12P Pons-Brooks
On December 4, periodic Comet 12P/Pons-Brooks shared this telescopic field of view with Vega, alpha star of the northern constellation Lyra. Fifth brightest star in planet Earth's night, Vega is some 25 light-years distant while the much fainter comet was about 21 light-minutes away.
Orion and the Ocean of Storms
On December 5, 2022, a camera on board the uncrewed Orion spacecraft captured this view as Orion approached its return powered flyby of the Moon. Beyond one of Orion's extended solar arrays lies dark, smooth, terrain along the western edge of the Oceanus Procellarum.