APOD: 2026 March 9 Б The Cranium Nebula from the Webb Telescope
9.03.2026

What's going on inside the head of this nebula? Dubbed the Exposed Cranium Nebula for its similarity to the human brain, what created the nebula remains a mystery. One thought is that the Cranium Nebula, also known as PMR 1, is a planetary nebula surrounding a white dwarf star.

Andromeda Island Universe
18.05.2002

How far can you see? The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy some two million light-years away. Without a telescope, even this immense spiral galaxy appears as an unremarkable, faint, nebulous cloud in the constellation Andromeda.

The Moon Maiden
19.06.2003

Along the northwestern reaches of the lunar near side, the Sinus Iridium or Bay of Rainbows appropriately lies at the edge of the Moon's smooth, dark Sea of Rains (Mare Imbrium). In this...

Solar Wind And Milky Way
4.03.1997

The Sun is bright, so bright that it overwhelms the light from other stars even for most satellite-borne telescopes. But LASCO, a coronograph onboard the space-based SOHO Observatory, uses occulting disks to block the intense solar light and examine the tenuous, hot gases millions of miles above the Sun's surface.

Mars Moons
24.10.2003

This year's record close approach of Mars inspired many to enjoy telescopic views of the red planet. But while Mars was so bright it was hard to miss, spotting Mars' two diminutive moons was still a good test for observers with modest sized instruments.

Green and Black Auroras Over Norway
29.03.2006

What causes gaps between aurora curtains? These unusual gaps can make Research using data from four Cluster spacecraft orbiting the Earth has likely found the secret: auroral gaps, sometimes knows as black auroras, are actually anti-auroras. In normal auroras, electrons and/or predominantly negatively charged particles fall toward Earth along surfaces of constant magnetic field.

Comet Lulin Tails
7.02.2009

Sweeping through the inner solar system, Comet Lulin is easily visible in both northern and southern hemispheres with binoculars or a small telescope. Recent changes in Lulin's lovely greenish coma and tails are featured in this two panel comparison of images taken on January 31st (top) and February 4th.

A Raging Storm System on Saturn
26.12.2011

It is one of the largest and longest lived storms ever recorded in our Solar System. First seen late last year, the above cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet.

All the Colors of the Sun
28.06.2015

It is still not known why the Sun's light is missing some colors. Here are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device.

Comet Machholz Approaches the Sun
13.11.2017

Why is Comet Maccholz so depleted of carbon-containing chemicals? Comet 96P/Machholz's original fame derives from its getting closer to the Sun than any other short period comet -- half as close as Mercury -- and doing so every five years.