Coronal Holes on the Sun
18.03.2003

The ominous, dark shapes haunting the left side of the Sun are coronal holes -- low density regions extending above the surface where the solar magnetic field opens freely into interplanetary space. Studied extensively from...

Comet Hale Bopp Over Val Parola Pass
9.04.2017

Comet Hale-Bopp, the Great Comet of 1997, became much brighter than any surrounding stars. It was seen even over bright city lights. Away from city lights, however, it put on quite a spectacular show. Here Comet Hale-Bopp was photographed above Val Parola Pass in the Dolomite mountains surrounding Cortina d'Ampezzo, Italy.

The Ion Tail of Comet Hyakutake
19.03.1996

This picture of Comet Hyakutake was taken on March 14, 1996. Structure in the ion tale of Comet Hyakutake is now clearly visible. An ion tale forms as a comet nears the Sun. Sunlight causes gas and dust to boil off the comet's solid nucleus.

Shadow Of A Comet
2.07.1999

Hale-Bopp, the Great Comet of 1997, may have been the most viewed comet in history - visible even from bright metropolitan skies. Astronomers are now reporting that this magnificent comet also cast a shadow against the glare of the solar system's ultraviolet haze.

Cosmic Rays at Voyager 1
8.09.2012

Launched on a grand tour of the outer planets in 1977, by good fortune the twin Voyager spacecraft were also headed in the general direction of the Sun's motion relative to nearby stars. Thirty five years later, Voyager 1 appears to be nearing the boundary of the Sun's heliosphere and interstellar space.

Discovery Image: Comet SOHO (1998 J1)
20.05.1998

Staring at the Sun from a vantage point in space (Kids, don't try this at home!), the Solar and Heliospheric Observatory (SOHO) has enabled the discovery of much about our closest star. It has also been used to discover about 50 comets.

Exploring Comet Tails
13.04.2000

Comets are known for their tails. In the spring of 1997 and 1996 Comet Hale-Bopp (above) and Comet Hyakutake gave us stunning examples as they passed near the Sun. These extremely active comets were...

Comet Leonards Tail Wag
10.01.2022

Why does Comet Leonard's tail wag? The featured time-lapse video shows the ion tail of Comet C/2021 A1 (Leonard) as it changed over ten days early last month. The video was taken by NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft that co-orbits the Sun at roughly the same distance as the Earth.

The Opposing Tails of Comet Garradd
28.02.2012

Why does Comet Garradd have two tails? Visible on the left, Comet Garradd's dust tail is composed of ice and dust bits that trial the comet in its orbit around the Sun. Visible...

The Long Tails of Comet NEOWISE
16.07.2020

This Comet NEOWISE (C/2020 F3) now sweeps through our fair planet's northern skies. Its long tails stretch across this deep skyview from Suchy Vrch, Czech Republic. Recorded on the night of July 13/14...