Abell 370


This Hubble image contains around 8,000 galaxies. It’s centered on a galaxy cluster known as Abell 370 which contains several hundred massive galaxies. The cluster is about 4 billion light-years away, and it’s huge mass functions as a gravitational lens which distorts the light coming from galaxies behind it.

Image Credit: ESA / NASA

11.1 Billion Light Years


CLJ1001+0220This image contains the most distant galaxy cluster, a discovery made using data from the Chandra X-ray Observatory and other telescopes. The galaxy cluster, known as CL J1001+0220, is about 11.1 billion light years from Earth. We may be seeing it right after its birth in a brief but important stage of cluster evolution never seen before.

There are eleven massive galaxies within about 250,000 light years of the central core of the cluster, and nine of them display high rates of formation. Specifically, stars are forming in the cluster core at a rate equivalent to about 3,400 Suns per year.

Image Credits: NASA/CXC/CEA/T. Wang et al; Infrared: ESO/UltraVISTA; Radio: ESO/NAOJ/NRAO/ALMA

A Cosmic Smile


A smiling lensThis is is the galaxy cluster SDSS J1038+4849, and it seems to be smiling with its two orange eyes and white button nose. The two eyes are very bright galaxies, and the misleading smile lines are arcs caused by an effect known as strong gravitational lensing.

Galaxy clusters are the most massive structures in the Universe and exert such a powerful gravitational pull that they warp the spacetime around them. They act as cosmic lenses which can magnify, distort, and bend the light coming from behind them. In this special case of gravitational lensing, a ring—known as an Einstein Ring—is produced by this bending of light. The gaps in the ring are a consequence of the inexact and not-quite-symmetrical alignment of the source, lens, and observer.

Image Credit: ESA / NASA

Internet Astronomy: Abell 1689


Abell 1689This Hubble image shows the massive galaxy cluster Abell 1689 and the phenomenon of gravitational lensing with unprecedented clarity. The cluster acts like a cosmic lens, magnifying the light from objects lying behind it and making it possible for astronomers to explore incredibly distant regions of space.

Abell 1689 has been found to also host a huge population of globular clusters. While our galaxy, the Milky Way, is home to around 150 of these old clumps of stars, astronomers estimate that this galaxy cluster could possibly contain a mind-boggling 160,000 globulars overall.

In addition to the glowing golden elliptical galaxies, bright stars, and distant, ethereal spiral galaxies, the picture shows a number of blue streaks, circling and arcing around the fuzzy galaxies in the center of the image (click on the image to embiggen it). Those streaks are the signs of gravitational lensing. Abell 1689 is so massive that it actually bends and warps the space around it, affecting how light from objects behind the cluster travels through space. The streaks are distorted forms of galaxies that lie beyond the cluster. While the galaxy cluster is just over 2 billion light-years away, the lensed galaxies are over 13 billion light-years distant and are among the oldest objects we can see in visible light.

Image Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), J. Blakeslee (NRC Herzberg Astrophysics Program, Dominion Astrophysical Observatory), and H. Ford (JHU)