Fermi Catalogs the Gamma ray Sky
18.03.2010

What shines in the gamma-ray sky? The most complete answer yet to that question is offered by the Fermi Gamma-ray Space Telescope's first all-sky catalog. Fermi's sources of cosmic gamma-rays feature nature...

ISS Transits Mars
23.09.2020

Yes, but have you ever seen the space station do this? If you know when and where to look, watching the bright International Space Station (ISS) drift across your night sky is a fascinating sight -- but not very unusual.

GRB 060218: A Mysterious Transient
27.02.2006

What is it? Something is happening in a small portion of the sky toward the constellation of Aries and telescopes around the globe are tracking an unusual transient there as it changes day by day. No one is sure what it will do next.

Plasma Jets from Radio Galaxy Hercules A
5.12.2012

Why does this galaxy emit such spectacular jets? No one is sure, but it is likely related to an active supermassive black hole at its center. The galaxy at the image center, Hercules A, appears to be a relatively normal elliptical galaxy in visible light.

APOD: 2023 September 20 Б Methane Discovered on Distant Exoplanet
20.09.2023

Where else might life exist? One of humanity's great outstanding questions, locating planets where extrasolar life might survive took a step forward in 2019 with the discovery of a significant amount of water vapor in the atmosphere of distant exoplanet K2-18b.

Centaurus Radio Jets Rising
13.04.2011

What if you could see the huge radio jets of Centaurus A rising? The Cen A radio jets are not only over a million light years long, they occupy an angular area over 200 times greater than the full Moon in Earth's sky.

A Distant Cluster of Galaxies
7.12.1997

In this 1994 Hubble Space Telescope photograph, every bright object is a galaxy. Oddly - most of them are spiral galaxies. This rich cluster of galaxies, named CL 0939+4713, is almost half way across the visible universe.

X-Rays From Sirius B
6.10.2000

In visible light Sirius A (Alpha Canis Majoris) is the brightest star in the night sky, a closely watched celestial beacon throughout recorded history. Part of a binary star system only 8 light-years away, it was known in modern times to have a small companion star, Sirius B.

Galaxy Cluster Abell 1689 Magnifies the Dark Universe
24.08.2010

What's the matter with this cluster of galaxies? To find out what forms matter takes in the Abell 1689 cluster requires not only deep images from telescopes like the Hubble Space Telescope, but detailed computer modeling as well. To start, almost every fuzzy yellow patch in the above image is an entire galaxy.

APOD: 2026 June 18 Б Possible Supernova Remnant in Galactic Center
18.06.2026

Do you see that blue blob to the lower right of the image center? Astronomers think that it shows where a massive star exploded as a supernova whose light reached Earth 1,700 years ago.