Fermi Epicyles: The Vela Pulsar s Path
4.05.2012

Exploring the cosmos at extreme energies, the Fermi Gamma-ray Space Telescope orbits planet Earth every 95 minutes. By design, it rocks to the north and then to the south on alternate orbits in order to survey the sky with its Large Area Telescope (LAT).

Caught in the Afterglow
24.11.2011

In this artist's illustration, two distant galaxies formed about 2 billion years after the big bang are caught in the afterglow of GRB090323, a gamma-ray burst seen across the Universe. Shining through...

The Farthest Explosion Yet Measured
19.10.2000

It happened so far away that common human distance measures are inadequate to describe it. Furthermore, astronomers do not even claim to know exactly what happened. What is known is that satellites across our Solar System reported on 2000 January 31 a tremendous explosion of gamma rays had occurred towards some previously uninteresting direction.

High Energy Stereoscopic System II
27.07.2012

The largest of its kind, the High Energy Stereoscopic System (H.E.S.S.) II telescope stands in the foreground of this photo. Tilted horizontally it reflects the inverted landscape of the Namibian desert in a segmented mirror 24 meters wide and 32 meters tall, equal in area to two tennis courts.

GW170817: A Spectacular Multiradiation Merger Event Detected
16.10.2017

Both gravitational and electromagnetic radiations have been detected in rapid succession for an explosive merging event for the first time. Data from the outburst fit well with a spectacular binary neutron-star death-spiral. The explosive episode was seen on August 17 in nearby NGC 4993, an elliptical galaxy only 130 million light years distant.

Optical Transient Near GRB970508 Shows Distant Redshift
13.05.1997

The GRB distance scale controversy may have just ended with a flash. Gamma Ray Bursts (GRBs) are powerful explosions occurring in seemingly random positions on the sky. They are so featureless and so poorly resolved, however, that their distances could not be determined.

The 220 Mirrors of CRTF
4.10.1999

Even the largest of modern optical telescopes are small when compared with the light gathering power of the Central Receiver Test Facility (CRTF) located in New Mexico, USA. CRTF has 220 mirrors each over 7-meters in diameter all focused on a single tower.

The Host Galaxies of Long Duration GRBs
17.05.2006

What causes the powerful explosions knows as gamma-ray bursts? Astrophysicists still aren't sure, but the longest duration gamma-ray bursts (GRBs) seem to involve very massive stars. A new clue indicating this was uncovered recently by a series of images taken by the orbiting Hubble Space Telescope.

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.

Neutrino Associated with Distant Blazar Jet
16.07.2018

With equipment frozen deep into ice beneath Earth's South Pole, humanity appears to have discovered a neutrino from far across the universe. If confirmed, this would mark the first clear detection of cosmologically-distant...