Chilean Skyscape
28.11.2008

Night skies over Chilean mountain top observatories can be dark and clear, with glorious cosmic vistas. In this recent example, the plane of our Milky Way galaxy stretches parallel to the horizon, the galactic center's star clusters, dark dust clouds, and glowing nebulae hovering in the west.

Perseids Around the Milky Way
16.08.2020

Why would meteor trails appear curved? The arcing effect arises only because the image artificially compresses (nearly) the whole sky into a rectangle. The meteors are from the Perseid Meteor Shower that peaked last week.

The Spider Nebula in Infrared
3.09.2019

Will the spider ever catch the fly? Not if both are large emission nebulas toward the constellation of the Charioteer (Auriga). The spider-shaped gas cloud on the left is actually an emission nebula labelled...

APOD: 2024 May 11 Б AR 3664: Giant Sunspot Group
10.05.2024

Right now, one of the largest sunspot groups in recent history is crossing the Sun. Active Region 3664 is not only big -- it's violent, throwing off clouds of particles into the Solar System. Some of these CMEs are already impacting the Earth, and others might follow.

APOD: 2025 June 14 Б Meteors and Satellite Trails over the Limay River
13.06.2025

What are all those streaks in the sky? A galaxy, many satellite trails, and a few meteors. First, far in the distance, the majestic band of our Milky Way Galaxy runs down the left. Mirroring it on the right are several parallel trails of Earth-orbiting Starlink satellites. Many fainter satellite trails also crisscross the image.

Star Trails Over Vienna
14.07.2005

As the Earth spins on its axis, the sky seems to rotate around us. This motion, called diurnal motion, produces the beautiful concentric trails traced by stars during time exposures. In the middle...

Is Mystery Object an Orphan Afterglow
11.11.2001

What is that unusual object? Astronomers can identify most objects that are imaged on the sky, but not all. Pictured above is one that currently defies classification. Attributes of the object include that it has unusual colors, appears to be fading as months go by, and appears to be associated with a distant galaxy.

The CMB Cold Spot
20.03.2011

How could part of the early universe be so cold? No one is sure, and many astronomers now think that the CMB Cold Spot on the cosmic microwave background (CMB) radiation is not particularly noteworthy. As the early universe expanded and cooled, it suddenly and predictably became transparent.

HI4PI: The Hydrogen Sky
23.10.2016

Where are the Milky Way's gas clouds and where are they going? To help answer this question, a new highest-resolution map of the sky in the universe's most abundant gas -- hydrogen -- has been completed and recently released, along with its underlying data.

The Magellanic Stream
15.08.2013

In an astronomical version of the search for the source of the Nile, astronomers now have strong evidence for the origin of the Magellanic Stream. This composite image shows the long ribbon...