Cosmic Rays at Voyager 1
8.09.2012

Launched on a grand tour of the outer planets in 1977, by good fortune the twin Voyager spacecraft were also headed in the general direction of the Sun's motion relative to nearby stars. Thirty five years later, Voyager 1 appears to be nearing the boundary of the Sun's heliosphere and interstellar space.

Stars and Dust in Corona Australis
18.10.2017

Blue dust clouds and young, energetic stars inhabit this telescopic vista, less than 500 light-years away toward the northern boundary of Corona Australis, the Southern Crown. The dust clouds effectively block light from more distant background stars in the Milky Way.

The Horsehead Nebula
27.12.2017

One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s.

The Horsehead Nebula from Blue to Infrared
28.07.2014

One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s.

Cosmic Latte: The Average Color of the Universe
27.12.2020

What color is the universe? More precisely, if the entire sky were smeared out, what color would the final mix be? This whimsical question came up when trying to determine what stars are commonplace in nearby galaxies. The answer, depicted above, is a conditionally perceived shade of beige. In computer parlance: #FFF8E7.

APOD: 2023 December 10 Б Big Dipper over Pyramid Mountain
10.12.2023

When did you first learn to identify this group of stars? Although they are familiar to many people around the world, different cultures have associated this asterism with different icons and folklore. Known...

Stars and Dust in Corona Australis
12.01.2020

Cosmic dust clouds and young, energetic stars inhabit this telescopic vista, less than 500 light-years away toward the northern boundary of Corona Australis, the Southern Crown. The dust clouds effectively block light from more distant background stars in the Milky Way.

Lingering Lunar Eclipse
26.07.2000

As the Moon passed almost directly through the center of Earth's shadow on July 16th, sky gazers in the Pacific hemisphere were graced by a lingering lunar eclipse. The total phase lasted 1 hour and 47 minutes, the longest since 1859. A longer total lunar eclipse won't occur until the year 3000.

RAPTOR Images GRB 021211
19.12.2002

On December 11 astronomers found one of the brightest and most distant explosions in the Universe - a gamma-ray burst - hiding in the glare of a relatively nearby star. The earliest image of the burst's visible light was caught by an earthbound RAPTOR (RAPid Telescopes for Optical Response).

A Close Encounter Of The Stellar Kind
11.12.1999

The unassuming star centered in this sky view will one day be our next door stellar neighbor. The faint 9th magnitude red dwarf, currently 63 light-years away in the constellation Ophiucus, was recently discovered to be approaching our Solar System.