Comet ATLAS over BrasíliaWhat’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 the Sun well inside the orbit of planet Mercury, going so close there was early c…Read More

Comet ATLAS Rounds the SunWhy 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 it was very hard for humans to see. But NASA’s SOHO spacecraft saw it.…Read More

Titan Touchdown: Huygens Descent MovieWhat 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 from the robotic Cassini spacecraft soon after it achieved orbit around Saturn in…Read More

Full Moon, Full MarsOn 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 from Richmond, Virginia, USA, this composite image sequence follows the evening lunar…Read More

Supernova Remnant Cassiopeia AMassive 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…Read More