APOD: 2025 May 9 Б IXPE Explores a Black Hole Jet
9.05.2025

How do black holes create X-rays? Answering this long-standing question was significantly advanced recently with data taken by NASAБs IXPE satellite. X-rays cannot exit a black hole, but they can be created in the energetic environment nearby, in particular by a jet of particles moving outward.

NGC 7293: The Helix Nebula
17.04.1996

The Helix nebula (New General Catalog number 7293) is estimated to be a mere 450 light-years from the Sun, in the direction of the constellation Aquarius. At that distance it may well be the closest planetary nebula, offering a dramatic snapshot of a brief final evolutionary stage in the life of a solar-type star.

Molecular Cloud Barnard 68
11.05.1999

Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark molecular cloud. Here, a high concentration of dust and molecular gas absorb practically all the visible light emitted from background stars.

NGC 7331 and Beyond
14.09.2023

Big, beautiful spiral galaxy NGC 7331 is often touted as an analog to our own Milky Way. About 50 million light-years distant in the northern constellation Pegasus, NGC 7331 was recognized early on as a spiral nebula and is actually one of the brighter galaxies not included in Charles Messier's famous 18th century catalog.

Barred Spiral Galaxy NGC 1300
12.01.2005

Big, beautiful barred spiral galaxy NGC 1300 lies some 70 million light-years away on the banks of the constellation Eridanus. This Hubble Space Telescope composite view of the gorgeous island universe was released...

A Telescope Laser Creates an Artificial Star
7.02.2005

What do you get when you combine one of the world's most powerful telescopes with a powerful laser? An artificial star. Monitoring fluctuations in brightness of a genuine bright star can indicate how the Earth's atmosphere is changing, but many times no bright star exists in the direction where atmospheric information is needed.

A Cliff Looming on Comet 67P
20.05.2015

What that looming behind this gravel-strewn hill on Comet ChuryumovGerasimenko? A jagged cliff. The unusual double-lobed nucleus of Comet 67P/ChuryumovGerasimenko lends itself to unusual and dramatic vistas, another of which has been captured by the Rosetta spacecraft that arrived at the comet last September.

Aurora over Clouds
24.11.2015

Auroras usually occur high above the clouds. The auroral glow is created when fast-moving particles ejected from the Sun impact the Earth's magnetosphere, from which charged particles spiral along the Earth's magnetic field to strike atoms and molecules high in the Earth's atmosphere.

Hidden Galaxy IC 342
29.01.2016

Similar in size to large, bright spiral galaxies in our neighborhood, IC 342 is a mere 10 million light-years distant in the long-necked, northern constellation Camelopardalis. A sprawling island universe, IC 342 would otherwise...

Arp 286: Trio in Virgo
10.06.2022

This colorful telescopic field of view features a trio of interacting galaxies almost 90 million light-years away, toward the constellation Virgo. On the right two spiky, foreground Milky Way stars echo the extragalactic hues, a reminder that stars in our own galaxy are like those in distant island universes.