Astronomy Picture Of the Day (APOD)Comet C 2017 K2 (PanSTARRS)
Imaged on June 20 2022, comet C/2017 K2 (PanSTARRS) shares this wide telescopic field of view with open star cluster IC 4665 and bright star Beta Ophiuchi, near a starry edge of the Milky Way.
Solar System Family Portrait
Yes, but have you ever seen all of the planets at once? A rare roll-call of planets has been occurring in the morning sky for much of June. The featured fisheye all-sky image, taken...
Mercury from Passing BepiColombo
Which part of the Moon is this? No part -- because this is the planet Mercury. Mercury's old surface is heavily cratered like that of Earth's Moon. Mercury, while only slightly larger than Luna, is much denser and more massive than any Solar System moon because it is made mostly of iron.
The Gum Nebula over Snowy Mountains
The Gum Nebula is so large and close it is actually hard to see. This interstellar expanse of glowing hydrogen gas frequently evades notice because it spans 35 degrees -- over 70 full Moons -- while much of it is quite dim.
Light Echoes from V838 Mon
What caused this outburst of V838 Mon? For reasons unknown, star V838 Mon's outer surface suddenly greatly expanded with the result that it became one of the brighter stars in the Milky Way Galaxy in early 2002. Then, just as suddenly, it shrunk and faded.
Planets of the Solar System
Simultaneous images from four cameras were combined to construct this atmospheric predawn skyscape. The cooperative astro-panorama captures all the planets of the Solar System, just before sunrise on June 24. That foggy morning found innermost planet Mercury close to the horizon but just visible against the twilight, below and left of brilliant Venus.
Filaprom on the Western Limb
A solar filament is an enormous stream of incandescent plasma suspended above the active surface of the Sun by looping magnetic fields. Seen against the solar disk it looks dark only because it's a little cooler, and so slightly dimmer, than the solar photosphere.
Supernova Remnant: The Veil Nebula
Ten thousand years ago, before the dawn of recorded human history, a new light would have suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was from a supernova, or exploding star, and record the expanding debris cloud as the Veil Nebula, a supernova remnant.
Analemma over Taipei
Does the Sun return to the same spot on the sky every day? No. A better and more visual answer to that question is an analemma, a composite of images taken at the same time and from the same place over the course of a year.
Rock Fingers on Mars
There, just right of center, what is that? The surface of Mars keeps revealing new surprises with the recent discovery of finger-like rock spires. The small nearly-vertical rock outcrops were imaged last month by the robotic Curiosity rover on Mars.