APOD: 2023 September 11 Б Beautiful Comet Nishimura
11.09.2023

This scene would be beautiful even without the comet. By itself, the sunrise sky is an elegant deep blue on high, with faint white stars peeking through, while near the horizon is a pleasing tan.

APOD: 2024 April 8 Б The Changing Ion Tail of Comet Pons Brooks
8.04.2024

How does a comet tail change? It depends on the comet. The ion tail of Comet 12P/PonsБBrooks has been changing markedly, as detailed in the featured image sequenced over nine days from March 6 to 14 (top to bottom).

Comet Pons-Brooks at Night
4.04.2024

In dark evening skies over June Lake, northern hemisphere, planet Earth, Comet 12P/Pons-Brooks stood just above the western horizon on March 30. Its twisted turbulent ion tail and diffuse greenish coma are captured in this two degree wide telescopic field of view along with bright yellowish star Hamal also known as Alpha Arietis.

APOD: 2024 June 4 Б Comet Pons Brooks Develops Opposing Tails
4.06.2024

Why does Comet Pons-Brooks now have tails pointing in opposite directions? The most spectacular tail is the blue-glowing ion tail that is visible flowing down the image. The ion tail is pushed directly out from the Sun by the solar wind. On the upper right is the glowing central coma of Comet 12P/PonsБBrooks.

APOD: 2024 April 17 Б Total Eclipse and Comets
17.04.2024

Not one, but two comets appeared near the Sun during last week's total solar eclipse. The expected comet was Comet 12P/Pons-Brooks, but it was disappointingly dimmer than many had hoped. However, relatively unknown Comet SOHO-5008 also appeared in long duration camera exposures.

APOD: 2024 March 18 Б Comet Pons Brooks Swirling Coma
18.03.2024

A bright comet will be visible during next month's total solar eclipse. This very unusual coincidence occurs because Comet 12P/Pons-Brooks's return to the inner Solar System places it by chance only 25 degrees away from the Sun during Earth's April 8 total solar eclipse.

Comet 12P/Pons Brooks in Northern Spring
9.03.2024

As spring approaches for northern skygazers Comet 12P/Pons-Brooks is growing brighter. Currently visible with small telescopes and binoculars the Halley-type comet could reach naked eye visibility in the coming weeks. Seen despite a foggy...

The Hydrogen Clouds of M33
26.12.2013

Gorgeous spiral galaxy M33 seems to have more than its fair share of glowing hydrogen gas. A prominent member of the local group of galaxies, M33 is also known as the Triangulum Galaxy and lies about 3 million light-years distant.

Comet 13P Olbers
28.06.2024

Not a paradox, Comet 13P/Olbers is returning to the inner Solar System after 68 years. The periodic, Halley-type comet will reach its next perihelion or closest approach to the Sun on June 30 and has become a target for binocular viewing low in planet Earth's northern hemisphere night skies.

A Dust Jet from the Surface of Comet 67P
6.11.2017

Where do comet tails come from? There are no obvious places on the nuclei of comets from which the jets that create comet tails emanate. Last year, though, ESA's Rosetta spacecraft not only imaged a jet emerging from Comet 67P/Churyumov-Gerasimenko, but flew right through it.