APOD: 2025 January 28 Б Comet G3 ATLAS over Uruguay
28.01.2025

Comets can be huge. When far from the Sun, a comet's size usually refers to its hard nucleus of ice and rock, which typically spans a few kilometers -- smaller than even a small moon.

APOD: 2023 January 31 Б A Triple View of Comet ZTF
31.01.2023

Comet ZTF has a distinctive shape. The now bright comet visiting the inner Solar System has been showing not only a common dust tail, ion tail, and green gas coma, but also an uncommonly distinctive antitail.

Comet C 2001 Q4 (NEAT)
23.04.2004

Inbound from the distant solar system, comet C/2001 Q4 will soon pass just inside planet Earth's orbit and should be one of two bright, naked-eye comets visible in southern skies in May. First...

Colors of Comet Pojmanski
11.03.2006

Comet Pojmanski flew by planet Earth last weekend on a surprise trip through the inner solar system. Then an easy binocular target for morning skygazers, Pojmanski ultimately showed off a long tail, but it also presented some lovely green-blue hues as gas molecules in its tenuous coma and tail fluoresced in the sunlight.

Comet Hale Bopp and the North America Nebula
3.10.2004

Comet Hale-Bopp's 1997 encounter with the inner Solar System allowed many breath-taking pictures. Above, Comet Hale-Bopp was photographed crossing the constellation of Cygnus, sporting spectacular yellow dust and blue ion tails. Visible on the right in red is the North America Nebula, a bright emission nebula observable from a dark location with binoculars.

Comet Lulin Approaches
2.02.2009

How bright will Comet Lulin become? No one knows for sure. Although it is notoriously difficult to accurately predict the brightness of newly discovered comets, Comet Lulin could well become visible to the unaided eye later this month.

APOD: 2023 September 9 Б Comet Nishimura Grows
9.09.2023

Comet Nishimura is growing. More precisely, the tails C/2023 P1 (Nishimura) are growing as it nears the Sun. Discovered only last month, the comet is already near naked eye brightness as it now moves inside the Earth's orbit.

Comet Castle
22.03.2013

The broad dust tail of Comet PanSTARRS (C/2011 L4) has become a familiar sight for many northern hemisphere comet watchers, as the comet fades but rises higher above the western horizon after sunset. This view of the popular comet may seem a little fantastic, though.

Comet LINEAR WM1 Shines in the South
4.02.2002

A new comet has brightened unexpectedly and is currently visible to unaided observers of southern skies. Comet C/2000 WM1 (LINEAR) is now reported by some observers to be at third magnitude, making it brighter -- although more diffuse -- than most visible stars. A dust tail as long as 3 degrees has also been reported.

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.