GRB 090423: The Farthest Explosion Yet Measured
29.04.2009

An explosion so powerful it was seen clear across the visible universe was recorded in gamma-radiation last week by NASA's orbiting Swift Observatory. Farther than any known galaxy, quasar, or optical supernova, the gamma-ray burst recorded last week was clocked at redshift 8.2, making it the farthest explosion of any type yet detected.

Arecibo: The Largest Telescope
9.03.1996

The Arecibo radio telescope is currently the largest single-dish telescope in the world. First opening in 1963, this 305 meter (1000 foot) radio telescope resides in a natural valley of Puerto Rico. The Arecibo...

Anemic Spiral NGC 4921 from Hubble
25.11.2013

How far away is spiral galaxy NGC 4921? Although presently estimated to be about 310 million light years distant, a more precise determination could be coupled with its known recession speed to help humanity better calibrate the expansion rate of the entire visible universe.

The Century that Defined Galaxy
30.12.1999

As the twentieth century dawned a debate raged over whether the Milky Way was the entire universe. The 1920s brought observations of spiral-nebulae that housed familiar but faint variable stars, and hence placed these nebulae much farther than anything else ever found. The Milky Way, apparently, is itself a spiral nebula seen from the inside.

The 100 Meter Green Bank Radio Telescope
11.03.2002

The largest single-dish fully steerable radio telescope began operation in 2000 August in Green Bank, West Virginia, USA. Dedicated as the Robert C. Byrd Green Bank Telescope, the device weighs over 30 times more than the Statue of Liberty, and yet can point anywhere in the sky more precisely than one thousandth of a degree.

Roque de los Muchachos Observatory
19.08.2002

Above the clouds, atop an island off the coast of Africa, a group of cutting-edge telescopes inspects the universe. Pictured above are telescopes at Roque de los Muchachos Observatory on La Palma, one of the Canary Islands, Spain. The site is one of the premier observing locations on Earth.

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 Orbiting Hubble Space Telescope
6.08.2001

The Hubble Space Telescope (HST) is the largest orbiting public optical telescope in history. Its 2.4 meter diameter reflecting mirror and its perch above Earth's atmosphere allow it to create exceptionally sharp images.

Cosmic Collisions in a Galaxy Cluster
22.07.1999

Hundreds of galaxies appear as faint smudges of light in this Hubble Space Telescope picture of galaxy cluster MS1054-03. Eight billion light-years away, the cluster is among the most distant known clusters of galaxies and is now reported to contain the largest number of colliding galaxies ever found in a cluster.

A Baby Galaxy
24.03.1998

What's the farthest galaxy known? The answer keeps changing as astronomers compete to find new galaxies which top the list. The new record holder is now the faint red smudge indicated in the above image by the arrow.