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 ...
M83: The Southern Pinwheel
Beautiful and bright spiral galaxy M83 lies a some twelve million light-years away, near the southeastern tip of the very long constellation Hydra. Prominent spiral arms traced by dark dust lanes and blue star clusters lend this galaxy its ...
Wolf Moon Engulfs Mars
Does the Moon ever engulf Mars? Yes, but only in the sense that it moves in front, which happens on rare occasions. This happened just yesterday, though, as seen from some locations in North America and western Africa. This occultation was ...
North Star: Polaris and Surrounding Dust
Why is Polaris called the North Star? First, Polaris is the nearest bright star toward the north spin axis of the Earth. Therefore, as the Earth turns, stars appear to revolve around Polaris, but Polaris itself always stays in the same northerly ...
Comet ATLAS Before Sunrise
Comet ATLAS is really bright now, but also really close to the Sun. Outside the glow of the Sun, Comet C/2024 G3 (ATLAS) would be one of the more remarkable comet sights of recent years, reflecting about as much sunlight to Earth as Comet ...
Mimas: Small Moon with a Big Crater
Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest round moons. Analysis indicates that a slightly larger impact would have destroyed Mimas entirely. The huge crater, ...
An Evening Sky Full of Planets
Only Mercury is missing from a Solar System parade of planets in this early evening skyscape. Rising nearly opposite the Sun, bright Mars is at the far left. The other naked-eye planets Jupiter, Saturn, and Venus, can also be spotted, with the ...
Young Stars, Dark Nebulae
An unassuming region in the constellation Taurus holds these dark and dusty nebulae. Scattered through the scene, stars in multiple star systems are forming within their natal Taurus molecular cloud complex some 450 light-years away. Millions of ...
Peculiar Galaxies of Arp 273
The colorful, spiky stars are in the foreground of this image taken with a small telescope on planet Earth. They lie well within our own Milky Way Galaxy. But the two eye-catching galaxies in the frame lie far beyond the Milky Way, at a distance ...
Supernova Remnants Big and Small
What happens after a star explodes? A huge fireball of hot gas shoots out in all directions. When this gas slams into the existing interstellar medium, it heats up so much it glows. Two different supernova remnants (SNRs) are visible in the ...
