Aurora Over Edmonton
3.11.2003

Northern and southern locales saw many a beautiful aurora over the last week, as particles from several large solar flares impacted the Earth. Many reported unusually red auroras, although colors across the spectrum were also seen. Power grids and orbiting satellites braced for the onslaught, but little lasting damage was reported.

The Kleinmann Low Nebula
1.03.1999

The most active part of the Orion Nebular Cloud Complex is an area known as the Kleinmann-Low Nebula. There, a cluster of young and forming stars is embedded in a molecular cloud filled with dust.

The Sun Unleashed: Monster Filament in Ultraviolet
8.04.2018

One of the most spectacular solar sights is an explosive flare. In 2011 June, the Sun unleashed somewhat impressive, medium-sized solar flare as rotation carried active regions of sunpots toward the solar limb. That...

Comet Schwassmann Wachmann 3 Passes the Earth
23.05.2006

Rarely does a comet pass this close to Earth. Last week, dedicated astrofilmographers were able to take advantage of the close approach of crumbling 73P / Comet Schwassmann-Wachmann 3 to make time-lapse movies of the fast-moving comet. Large comet fragments passed about 25 times the Moon's distance from the Earth.

APOD: 2024 December 23 Б Christmas Tree Aurora
22.12.2024

It was December and the sky lit up like a Christmas tree. Shimmering, the vivid green, blue, and purple auroral colors that formed the tree-like apparition were caused by high atmospheric oxygen and nitrogen reacting to a burst of incoming electrons.

NGC 3603: An Active Star Cluster
18.10.1999

NGC 3603 is home to a massive star cluster, thick dust pillars, and a star about to explode. The central open cluster contains about 2000 bright stars, each of which is much brighter and more massive than our Sun.

Coronal Rain, Solar Storm
14.11.2000

In this picture, the Sun's surface is quite dark. A frame from a movie recorded on November 9th by the orbiting TRACE telescope, it shows coronal loops lofted over a solar active region.

APOD: 2023 December 11 Б Solar Minimum versus Solar Maximum
10.12.2023

The surface of our Sun is constantly changing. Some years it is quiet, showing relatively few sunspots and active regions. Other years it is churning, showing many sunspots and throwing frequent Coronal Mass Ejections (CMEs) and flares.

Comet Hale Bopp in the Outer Solar System
26.03.2001

Whatever became of Comet Hale-Bopp? The brightest comet in recent years has continued into the outer Solar System and is now further from the Sun than Saturn. To the surprise of many, Comet Hale-Bopp is still active, continuing to spew gas, ice and dust particles out into space.

Solar Flare from a Sharper Sun
21.11.2014

Solar active region AR2192 was the largest recorded sunspot group of the last 24 years. Before rotating off the Earth-facing side of the Sun at the end of October, it produced a whopping six energetic X-class flares.