Andromeda Island Universe
30.04.2020

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.

Universe Age from the Microwave Background
17.02.2003

The above sky map tells us the universe is 13.7 billion years old -- but how? At first look, one only sees the microwave glow of gas from our Milky Way Galaxy, coded red, and a spotty pattern of microwaves emitted from the early universe, coded in gray.

Galaxy Zoo Catalogs the Universe
26.10.2009

You, too, can Zoo. The Galaxy Zoo project has been enabling citizen scientists -- inquisitive people like yourself armed with only a web browser-- to sort through the universe. Specifically, after a brief training session...

The Local Void in the Nearby Universe
6.08.2019

What does our region of the Universe look like? Since galaxies are so spread out over the sky, and since our Milky Way Galaxy blocks part of the distant sky, it has been hard to tell.

Island Universe, Cosmic Sand
2.08.2003

On August 13, 2002, while counting Perseid meteors under dark, early morning Arizona skies, Rick Scott set out to photograph their fleeting but fiery trails. The equipment he used included a telephoto lens and fast color film. After 21 pictures he'd caught only two meteors, but luckily this was one of them.

APOD: 2023 January 18 Б MACS0647: Gravitational Lensing of the Early Universe by Webb
18.01.2023

Gravitational lensing by the galaxy cluster MACS0647 -- in which the massive foreground cluster distorts and lenses the light emitted by distant background galaxies along the line of sight Б is on vivid display here in this recent multi-color infrared image from the James Webb Space Telescope (JWST).

Nobels for a Strange Universe
9.10.2011

Thirteen years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant is directly implied by new distant supernova observations.

Dark Matter in a Simulated Universe
25.10.2020

Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters...

The Observable Universe
16.03.2022

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 light...

NGC 253: Dusty Island Universe
22.03.2018

Shiny NGC 253 is one of the brightest spiral galaxies visible, and also one of the dustiest. Some call it the Silver Dollar Galaxy for its appearance in small telescopes, or just the Sculptor Galaxy for its location within the boundaries of the southern constellation Sculptor.