Noctilucent NEOWISE
8.07.2020

These silvery blue waves washing over a tree-lined horizon in the eastern French Alps are noctilucent clouds. From high in planet Earth's mesosphere, they reflect sunlight in this predawn skyscape taken on July 8. This summer, the night-shining clouds are not new to the northern high-latitudes. Comet NEOWISE is though.

A High Cliff on Comet Churyumov Gerasimenko
27.11.2021

This high cliff occurs not on a planet, not on a moon, but on a comet. It was discovered to be part of the dark nucleus of Comet Churyumov-Gerasimenko (CG) by Rosetta, a robotic spacecraft launched by ESA that rendezvoused with the Sun-orbiting comet in 2014.

Comet Leonards Long Tail
2.01.2022

You couldn't see Comet LeonardБs extremely long tail with a telescope Б it was just too long. You also couldn't see it with binoculars Б still too long. Or with your eyes -- it was too dim. Or from a city Б the sky was too bright.

Comet C/2025 F2 SWAN
17.04.2025

In late March, the comet now designated C/2025 F2 SWAN was found independently by citizen scientists Vladimir Bezugly, Michael Mattiazzo, and Rob Matson while examining publicly available image data from the Solar Wind ANisotropies (SWAN) camera on the sun-staring SOHO spacecraft.

Comet NEOWISE Rising over the Adriatic Sea
25.07.2022

This sight was worth getting out of bed early. Two years ago this month, Comet C/2020 F3 (NEOWISE) rose before dawn to the delight of northern sky enthusiasts awake that early. Up before sunrise...

APOD: 2025 January 20 Б Comet ATLAS Rounds the Sun
19.01.2025

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 it was very hard for humans to see. But NASA's SOHO spacecraft saw it.

APOD: 2025 January 21 Б Comet ATLAS over Brasilia
20.01.2025

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 Brasцlia, Brazil four days ago.

Comet G3 ATLAS: a Tail and a Telescope
23.01.2025

Comet C/2024 G3 ATLAS has made a dramatic appearance in planet Earth's skies. A visitor from the distant Oort Cloud, the comet reached its perihelion on January 13. On January 19, the bright comet was captured here from ESO Paranal Observatory in the Atacama desert in Chile.

APOD: 2025 January 26 Б The Many Tails of Comet G3 ATLAS
25.01.2025

Why does this comet have so many tails? C/2024 G3 (ATLAS) has developed several long and intricate tails visible from Earth's southern hemisphere over the past two weeks. Many observers reported seeing the impressive comet without any optical aid above the western horizon just after sunset.

APOD: 2025 February 5 Б Comet G3 ATLAS Setting over a Chilean Hill
4.02.2025

Where is Comet ATLAS going? In the featured time-lapse video, the comet is not itself moving very much, but the Earth's rotation makes it appear to be setting over a hill. The Comet C/2024 G3 (ATLAS) sequence was captured with an ordinary camera on January 22 from the Araucanцa Region in central Chile.