A Darkened Sky
20.09.2008

For a moment on August 1st, the daytime sky grew dark along the path of a total solar eclipse. While watching the geocentric celestial event from Mongolia, photographer Miloslav Druckmuller recorded multiple images with two separate cameras as the Moon blocked the bright solar disk and darkened the sky.

At the Heart of Orion
6.10.2012

Near the center of this sharp cosmic portrait, at the heart of the Orion Nebula, are four hot, massive stars known as the Trapezium. Gathered within a region about 1.5 light-years in radius, they dominate the core of the dense Orion Nebula Star Cluster.

NGC 4762: A Galaxy on the Edge
4.11.2014

Why is there a bright line on the sky? What is pictured above is actually a disk galaxy being seen almost perfectly edge on. The image from the Hubble Space Telescope is a spectacular visual reminder of just how thin disk galaxies can be.

NGC 6357: Cathedral to Massive Stars
27.03.2016

How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known.

Stars and Dust in Corona Australis
20.09.2018

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.

NGC 6188: The Dragons of Ara
7.11.2018

Dark shapes with bright edges winging their way through dusty NGC 6188 are tens of light-years long. The emission nebula is found near the edge of an otherwise dark large molecular cloud in the southern constellation Ara, about 4,000 light-years away.

APOD: 2025 January 28 Б Comet G3 ATLAS over Uruguay
28.01.2025

Comets can be huge. When far from the Sun, a comet's size usually refers to its hard nucleus of ice and rock, which typically spans a few kilometers -- smaller than even a small moon.

APOD: 2025 July 26 Б Globular Cluster Omega Centauri
26.07.2025

Globular star cluster Omega Centauri packs about 10 million stars much older than the Sun into a volume some 150 light-years in diameter. Also known as NGC 5139, at a distance...

Asteroid 3753: Earth's Curious Companion
18.06.1997

Earth is not alone. It orbits the Sun with a small companion: Asteroid 3753. First discovered in 1986 and designated 1986 OT, this five kilometer rock was recently found to orbit the Sun while executing a strange dance with the Earth. A portion of the asteroid's complex orbit is shown above.

Galactic Center Star Clusters
10.08.2006

If you had x-ray vision, the central regions of our Galaxy would not be hidden from view by cosmic dust clouds. Instead, the Milky Way toward Sagittarius might look something like this. Pleasing...