APOD: 2026 March 10 Б Sky Glows over Paranal Observatory
10.03.2026

Are lasers from giant telescopes being used to defend the Earth? No. Lasers shot from telescopes are now commonly used to help increase the accuracy of astronomical observations. In some directions, Earth atmosphere-induced fluctuations in starlight can indicate how the air mass over a telescope is changing, but in other directions, no bright star exists.

Comet Lovejoy in a Winter Sky
27.01.2015

Which of these night sky icons can you find in this beautiful and deep exposure of the northern winter sky? Skylights include the stars in Orion's belt, the Orion Nebula, the Pleiades star cluster, the bright stars Betelgeuse and Rigel, the California Nebula, Barnard's Loop, and Comet Lovejoy.

BATSE GRB Final Sky Map
28.06.2000

What causes the most powerful explosions in the universe? The BATSE modules that flew on the Compton Gamma Ray Observatory allowed more insight into enigmatic gamma-ray burst (GRB) explosions than ever before. From 1991-2000, BATSE detected 2704 GRBs, much more than ever previously recorded.

Firing Lasers to Tame the Sky
10.02.2021

Why do stars twinkle? Our atmosphere is to blame as pockets of slightly off-temperature air, in constant motion, distort the light paths from distant astronomical objects. Atmospheric turbulence is a problem for astronomers because it blurs the images of the sources they want to study.

Dark Skies: Turn on the Night
16.05.2019

Have you ever experienced a really dark night sky? One common and amazing feature is the glowing band of our Milky Way galaxy stretching from horizon to horizon. If you live in or near...

September Sky
29.09.2000

Star clusters, planets, and a red giant posed for this portrait of the night sky from rural Jasper County, Iowa, USA. Astrophotographer Stan Richard recorded the four minute time exposure looking east around midnight on September 3rd at Ashton-Wildwood Park.

Dark Markings of the Sky
25.04.2009

Based on wide field photographs, American astronomer Edward Emerson Barnard cataloged the dark markings of the sky in the early 20th century. Barnard's markings are dark nebulae, interstellar clouds of obscuring gas and dust.

APOD: 2024 August 21 Б Fermis 12 year All Sky Gamma ray Map
21.08.2024

Forget X-ray vision Б imagine what you could see with gamma-ray vision! The featured all-sky map shows what the universe looks like to NASA's Fermi Gamma-ray Space Telescope. Fermi sees light with energies about a billion times what the human eye can see, and the map combines 12 years of Fermi observations.

All Sky Steve
14.10.2017

Familiar green and red tinted auroral emission floods the sky along the northern (top) horizon in this fish-eye panorama projection from September 27. On the mild, clear evening the Milky Way tracks through the zenith of a southern Alberta sky and ends where the six-day-old Moon sets in the southwest.

Southern Ocean Sky
4.07.2011

Clouds and sky both show illuminating changes during this time lapse video from the south of Australia. In the foreground are scenes visible over a rocky coastline toward the Southern Ocean. Dark clouds flow...