Comet Hartley 2 Flyby
5.11.2010

Follow these 5 frames clockwise starting from the top left to track the view from the EPOXI mission spacecraft as it approached, passed under, and then looked back at the nucleus of comet Hartley 2 on November 4. Its closest approach distance was about 700 kilometers.

Two Tails of Comet West
26.08.1995

Here Comet West is seen showing two enormous tails that wrap around the sky. The ion tale of a comet usually appears more blue and always points away from the Sun. The dust tail trailing the comet's nucleus is the most prominent.

Rosetta Approaches Comet Churyumov Gerasimenko
11.08.2014

What does it look like to approach a comet? Early this month humanity received a new rendition as the robotic Rosetta spacecraft went right up to -- and began orbiting -- the nucleus of Comet 67P/Churyumov-Gerasimenko.

Meteor, Comet, and Seagull (Nebula)
21.10.2018

A meteor, a comet, and a photogenic nebula have all been captured in this single image. The closest and most fleeting is the streaking meteor on the upper right -- it was visible for less than a second.

Perihelion Approaches
15.08.2015

This dramatic outburst from the nucleus of Comet 67P/Churyumov-Gerasimenko occured on August 12, just hours before perihelion, its closest approach to the Sun. Completing an orbit of the Sun once every 6.45 years, perihelion distance for this periodic comet is about 1.3 astronomical units (AU), still outside the orbit of planet Earth (at 1 AU).

APOD: 2025 October 6 Б The Changing Ion Tail of Comet Lemmon
6.10.2025

How does a comet tail change? It depends on the comet. The ion tail of Comet C/2025 A6 (Lemmon) has been changing markedly, as detailed in the featured image sequenced over six days between September 25 and October 4 (left to right) from Texas, USA.

LINEAR s Tail and Two Nuclei
31.05.2001

Arcing toward southern skies in late March, this faint comet LINEAR - the one officially designated C/2001 A2 (LINEAR) - brightened unexpectedly. The outburst, apparently due to the fragmentation of its nucleus, delighted observers as the comet eventually increased to naked-eye brightness.

An Orbiting Iceberg
21.08.1995

A comet nucleus, formed from the primordial stuff of the solar system, resembles a very dirty iceberg. Orbiting far from our Sun, it can remain frozen, preserved for billions of years. Occasionally, a chance gravitational encounter will alter this distant orbit and send the nucleus plummeting towards the inner solar system.

The Inner Coma of Comet Holmes
13.11.2007

What's happening to Comet Holmes? The rare comet remains visible to the unaided eyes of northern observers as an unusual small puff ball in the constellation of Perseus. A high resolution set of images of the comet's inner coma, taken last week and shown above, reveals significant detail.

Comet Holmes in Outburst
26.10.2007

Comet 17P/Holmes stunned comet watchers across planet Earth earlier this week. On October 24, it increased in brightness over half a million times in a matter of hours. The outburst transformed it from...