A Prominence on the Sun
19.09.2015

This eerie landscape of incandescent plasma suspended in looping and twisted magnetic fields stretched toward the Sun's eastern horizon on September 16. Captured through a backyard telescope and narrowband filter in light from ionized hydrogen, the scene reveals a gigantic prominence lofted above the solar limb.

A Moon Dressed Like Saturn
2.08.2022

Why does Saturn appear so big? It doesn't -- what is pictured are foreground clouds on Earth crossing in front of the Moon. The Moon shows a slight crescent phase with most of its surface visible by reflected Earthlight known as ashen glow.

Grand Design Spiral Galaxy NGC 2997
30.10.1996

NGC 2997 is a grand design spiral galaxy. Its small nucleus and sprawling spiral arms give it a type "Sc" designation. NGC 2997 is speeding away from us at about 1100 kilometers...

The Small Cloud of Magellan
19.09.1995

Almost unknown to casual observers in the northern hemisphere, the southern sky contains two diffuse wonders known as the Magellanic Clouds. The Magellanic Clouds are small irregular galaxies orbiting our own larger Milky Way spiral galaxy.

The Cygnus Loop
26.07.1996

15,000 years ago a star in the constellation of Cygnus exploded -- the shockwave from this supernova explosion is still expanding into interstellar space! The collision of this fast moving wall of gas with...

Ocean Planet Pole To Pole
7.10.1998

The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) instrument onboard the orbiting SeaStar spacecraft can map subtle differences in Earth's ocean color. These North (left) and South Pole projections are based on SeaWiFS measurements made between September 1997 and July 1998.

Filaments Across the Sun
6.12.2004

Two unusually long filaments crossed part of the Sun last week. The filaments are actually relatively cool and dark prominences of solar plasma held up by the Sun's magnetic field but seen against the face of the Sun. Filaments typically last a few weeks before falling back.

Crescent Neptune and Triton
14.04.2013

Gliding silently through the outer Solar System, the Voyager 2 spacecraft camera captured Neptune and Triton together in crescent phase in 1989. The elegant picture of the gas giant planet and its cloudy moon was taken from behind just after closest approach.

Fire on Earth
1.09.2013

Sometimes, regions of planet Earth light up with fire. Since fire is the rapid acquisition of oxygen, and since oxygen is a key indicator of life, fire on any planet would be an indicator of life on that planet.

Aurora and Milky Way in a Little Sky
3.10.2014

Stepping stones seem to lead to the Milky Way as it stretches across this little sky. Of course, the scene is really the northern hemisphere's autumnal equinox night. Water and sky are inverted...