APOD: 2025 September 16 Б New Comet SWAN25B over Mexico
16.09.2025

A newly discovered comet is already visible with binoculars. The comet, C/2025 R2 (SWAN) and nicknamed SWAN25B, is brightening significantly as it emerges from the Sun's direction and might soon become visible on your smartphone -- if not your eyes.

APOD: 2025 September 18 Б Comet C/2025 R2 SWAN
18.09.2025

A new visitor from the outer Solar System, comet C/2025 R2 (SWAN) also known as SWAN25B was only discovered late last week, on September 11. That's just day before the comet reached perihelion, its closest approach to the Sun.

Meteors, Comet, and Big Dipper over La Palma
23.04.2019

Meteor showers are caused by streams of solid particles, dust size and larger, moving as a group through space. In most cases, the orbits of these meteor streams can be identified with dust expelled from a comet.

Interstellar Comet 2I Borisov
14.12.2019

From somewhere else in the Milky Way galaxy, Comet 2I/Borisov is just visiting the Solar System. Discovered by Crimean amateur astronomer Gennady Borisov on August 30, 2019, the first known interstellar comet is captured in these two recent Hubble Space Telescope images.

Comet 45P Passes Near the Earth
12.02.2017

A large snowball has just passed the Earth. Known as Comet 45P/HondaMrkosPajduАkovА", or 45P for short, the comet came 10 times closer to Earth yesterday than the Earth ever gets to the Sun. During this passage, the comet was photographed sporting a thin ion tail and a faint but expansive green coma.

Almost Three Tails for Comet Encke
20.02.2017

How can a comet have three tails? Normally, a comet has two tails: an ion tail of charged particles emitted by the comet and pushed out by the wind from...

The Comet, the Owl, and the Galaxy
24.03.2017

Comet 41P/Tuttle-Giacobini-Kresak poses for a Messier moment in this telescopic snapshot from March 21. In fact it shares the 1 degree wide field-of-view with two well-known entries in the 18th century comet-hunting astronomer's famous catalog.

Comet, Clusters, and Nebulae
13.09.2018

Bright enough for binocular viewing Comet 21P / Giacobini-Zinner stands out, even in this deep telephoto mosaic of the star cluster and nebula rich constellation Auriga the Charioteer. On the night of September...

Two Comets in Southern Skies
8.10.2022

Heading for its closest approach to the Sun or perihelion on December 20, comet C/2017 K2 (PanSTARRS) remains a sight for telescopic observers as it sweeps through planet Earth's southern hemisphere skies. First...

The Tail of a Christmas Comet
25.12.2021

The tail of a comet streams across this three degree wide telescopic field of view captured under dark Namibian skies on December 21. In outburst only a few days ago and just reaching naked eye visibility Comet Leonard (C/2021 A1) is this year's brightest comet.