The Observable Universe
8.05.2018

How far can you see? Everything you can see, and everything you could possibly see, right now, assuming your eyes could detect all types of radiations around you -- is the observable universe. In visible...

A Phoenix Aurora over Iceland
3.01.2021

All of the other aurora watchers had gone home. By 3:30 am in Iceland, on a quiet September night, much of that night's auroras had died down. Suddenly, unexpectedly, a new burst of particles streamed down from space, lighting up the Earth's atmosphere once again.

Saturn and Six Moons
6.07.2021

How many moons does Saturn have? So far 82 have been confirmed, the smallest being only a fraction of a kilometer across. Six of its largest satellites can be seen here in a composite...

Orion Pines
16.04.2022

Taken with a camera fixed to a tripod, many short exposures were aligned with the stars to unveil this beautiful, dark night sky. Captured near the rural village of Albany`a at the northeastern corner of Spain, the three stars of Orion's belt stretch across top center in the starry frame.

APOD: 2023 July 18 Б Milky Way above La Palma Observatory
18.07.2023

What's happening in the night sky? To help find out, telescopes all over the globe will be pointing into deep space. Investigations will include trying to understand the early universe, finding and tracking Earth-menacing asteroids, searching for planets that might contain extra-terrestrial life, and monitoring stars to help better understand our Sun.

APOD: 2025 June 24 Б In the Center of Spiral Galaxy M61
24.06.2025

Is there a spiral galaxy in the center of this spiral galaxy? Sort of. Image data from the Hubble Space Telescope, the European Southern Observatory, and smaller telescopes on planet Earth are combined in this detailed portrait of face-on spiral galaxy Messier 61 (M61) and its bright center.

Jupiter s Brain
1.02.2001

Gas giant Jupiter is the solar system's largest world with about 320 times the mass of planet Earth. Famous for its Great Red Spot, Jupiter is also known for its regular, equatorial cloud bands, visible in very modest sized telescopes.

Annular Eclipse: The Ring of Fire
10.06.2002

Today, a few lucky people will see a "ring of fire." That's a name for the central view of an annular eclipse of the Sun by the Moon. At the peak of this...

The Milky Way Behind an Eclipsed Moon
3.06.2003

What's behind the Moon? Each month, our Moon passes in front of -- and outshines -- many an interesting star field. Exceptions occur during a new Moon and during a total eclipse. In the background...

Iridium Flare
2.04.1998

Have you seen an Iridium flare? Satellites in low Earth orbit reflect sunlight and are often visible gliding across early evening and predawn skies. But sun glints from Iridium commercial digital communications satellites are providing the most spectacular sightings.