Gamma Ray Earth and Sky
6.12.2013

For an Earth-orbiting gamma-ray telescope, Earth is actually the brightest source of gamma-rays, the most energetic form of light. Gamma-rays from Earth are produced when high energy particles, cosmic rays from space, crash into the atmosphere.

Abell 2218: A Galaxy Cluster Lens
20.06.2010

What are those strange filaments? Background galaxies. Gravity can bend light, allowing huge clusters of galaxies to act as telescopes, and distorting images of background galaxies into elongated strands. Almost all of the bright objects in this Hubble Space Telescope image are galaxies in the cluster known as Abell 2218.

M16: Pillars of Star Creation
6.12.2020

These dark pillars may look destructive, but they are creating stars. This pillar-capturing image of the inside of the Eagle Nebula, taken with the Hubble Space Telescope in 1995, shows evaporating gaseous globules (EGGs) emerging from pillars of molecular hydrogen gas and dust.

A String Of Pearls
13.07.1995

Comet Shoemaker-Levy 9, named after its co-discoverers, was often referred to as the "string of pearls" comet. It is famous for its unusual appearance as well as its collision with the planet Jupiter!

Crosby Ramsey Memorial Observatory Refractor
14.01.1999

The Massachusetts-based firm of Alvan Clark and Sons became famous for making telescope optics near the end of the last century. Near the end of this century, major astronomical observatories still boast of telescopes...

The GRB 110328A Symphony
19.04.2011

A symphony of planet-wide observations began abruptly on March 28 when the Earth-orbiting Swift satellite detected a burst of high-frequency gamma-rays from GRB 110328A. When the same source flared again after a 45 minute pause it was clear this event was not a typical gamma-ray burst.

Perseids and MAGIC
11.08.2022

On August 11, 2021 a multi-mirror, 17 meter-diameter MAGIC telescope reflected this starry night sky from the Roque de los Muchachos European Northern Observatory on the Canary Island of La Palma. MAGIC stands for Major Atmospheric Gamma Imaging Cherenkov.

The Pleiades Star Cluster
6.05.2001

It is the most famous star cluster on the sky. The Pleiades can be seen without binoculars from even the depths of a light-polluted city. Also known as the Seven Sisters and M45, the Pleiades is one of the brightest and closest open clusters.

Orion over Green Bank
23.02.2022

What will the huge Green Bank Telescope discover tonight? Pictured, the Robert C. Byrd Green Bank Telescope (GBT) on the lower right is the largest fully-pointable single-dish radio telescope in the world. With...

Star Clouds Toward the Southern Crown
2.10.2002

The flowing trails of dust toward Corona Australis, the constellation of the Southern Crown, are visible here because not because they glow, but because they absorb and reflect. The dust appears bluer when seen near bright stars because it preferentially reflects blue light.