Comet ATLAS over Brasília
What's that in the sky? Above the city, above most clouds, far in the distance: it's a comet. Pictured, the impressive tail of Comet C/2024 G3 (ATLAS) was imaged from Brasília, Brazil four days ago. Last week the evolving comet rounded ...
Comet ATLAS Rounds the Sun
Why does Comet ATLAS have such colorful tails? Last week Comet C/2024 G3 (ATLAS) passed its closest to the Sun -- well inside the orbit of Mercury -- and brightened dramatically. Unfortunately, the comet was then so angularly near the Sun that ...
Titan Touchdown: Huygens Descent Movie
What would it look like to land on Saturn's moon Titan? The European Space Agency's Huygens probe set down on the Solar System's cloudiest moon in 2005, and a time-lapse video of its descent images was created. Huygens separated ...
Full Moon, Full Mars
On January 13 a Full Moon and a Full Mars were close, both bright and opposite the Sun in planet Earth's sky. In fact Mars was occulted, passing behind the Moon, when viewed from some locations in North America and northwest Africa. As seen ...
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, ...
