Andromeda Island Universe
24.01.2008

The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy some two and a half million light-years away. But without a telescope, even this immense spiral galaxy - spanning over 200,000 light years - appears as a faint, nebulous cloud in the constellation Andromeda.

The Heart in NGC 346
14.02.2003

Yes, it's Valentine's Day (!) and looking toward star cluster NGC 346 in our neighboring galaxy the Small Magellanic Cloud, astronomers have noted this heart-shaped cloud of hot, x-ray emitting gas in the cluster's central region.

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...

M33: Triangulum Galaxy
20.12.2012

The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way.

The Red Rectangle Nebula from Hubble
9.05.2018

How was the unusual Red Rectangle nebula created? At the nebula's center is an aging binary star system that surely powers the nebula but does not, as yet, explain its colors. The unusual...

A View from Next Door
18.10.2012

Located just next door, Alpha Centauri is the closest star system to the Sun. A view from our interstellar neighbor a mere 4.3 light-years away is shown in this illustration. The Sun is at the upper right, a bright star against the background of the Milky Way.

Andromeda Island Universe
8.09.2000

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

Andromeda Island Universe
22.12.2005

The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy some two million light-years away. But without a telescope, even this immense spiral galaxy - spanning over 200,000 light years - appears as a faint, nebulous cloud in the constellation Andromeda.

The Red Rectangle Nebula from Hubble
14.06.2010

How was the unusual Red Rectangle nebula created? At the nebula's center is a young binary star system that surely powers the nebula but does not, as yet, explain its colors. The unusual...

APOD: 2026 January 5 Б The Red Rectangle Nebula from Hubble
5.01.2026

How was the unusual Red Rectangle nebula created? At the nebula's center is an aging binary star system that surely powers the nebula but does not, as yet, explain its colors. The unusual...