HESS Telescopes Explore the High Energy Sky
8.01.2019

They may look like modern mechanical dinosaurs but they are enormous swiveling eyes that watch the sky. The High Energy Stereoscopic System (H.E.S.S.) Observatory is composed of four 12-meter reflecting-mirror telescopes surrounding a larger telescope housing a 28-meter mirror.

An Atlas Centaur Rocket Launches
14.12.1995

Atlas Centaur rockets have launched over 75 successful unmanned missions. These missions included the Surveyor series - the first vehicles to make soft landings on the Moon, Pioneer 10 and 11 - the first missions...

SIRTF Streak
5.09.2003

Streaking skyward, a Boeing Delta 2-Heavy rocket carries NASA's Space InfraRed Telescope Facility (SIRTF) aloft during the early morning hours of August 25th. The dramatic scene was recorded in a time exposure from...

APOD: 2024 December 11 Б The Shells and Jets of Galaxy Centaurus A
11.12.2024

What's the closest active galaxy to planet Earth? That would be Centaurus A, cataloged as NGC 5128, which is only 12 million light-years distant. Forged in a collision of two otherwise normal galaxies...

Distant Neutrinos Detected Below Antarctic Ice
1.09.2015

From where do these neutrinos come? The IceCube Neutrino Observatory near the South Pole of the Earth has begun to detect nearly invisible particles of very high energy. Although these rarely-interacting neutrinos pass through much of the Earth just before being detected, where they started remains a mystery.

ASCA X-Ray Observatory
20.02.1996

Today marks the third anniversary of the launch of the Advanced Satellite for Cosmology and Astrophysics (ASCA; renamed from Astro D when launched). ASCA, seen here superposed on galaxy M31, is a Japanese satellite for which NASA has provided some scientific equipment. ASCA carries four large-area X-ray telescopes.

The Compton Observatory Turns Five
13.04.1996

Earlier this April, NASA's Compton Gamma Ray Observatory, completed its fifth successful year in orbit, exploring the gamma ray sky. Pictured is astronaut Jay Apt perched in the shuttle payload bay below the massive observatory. Compton is the largest civilian instrument ever flown - the whole observatory is roughly the size of a school bus.

Vela Satellites: The Watchers
5.11.1995

In October of 1963 the US Air Force launched the first in a series of satellites inspired by a recently signed nuclear test ban treaty. Signatories of this treaty agreed not to test nuclear devices in the atmosphere or in space.

Spiraling Supermassive Black Holes
3.12.2018

Do black holes glow when they collide? When merging, co-orbiting black holes are sure to emit a burst of unusual gravitational radiation, but will they emit light, well before that, if they are surrounded by gas? To help find out, astrophysicists created a sophisticated computer simulation.

Vintage Gamma Rays
6.04.2002

Gamma-rays are the most energetic form of electromagnetic radiation. But these high energy photons penetrate and interact in normal materials and cannot be focused by lenses and mirrors like those in optical telescopes. So how do you make an image in gamma-ray light?