Looking Through Abell
68
Want to use a cluster of galaxies as a telescope? It's easier than you might think as distant galaxy clusters naturally act
as strong gravitational lenses.
In accordance with
Einstein's theory of general relativity, the cluster gravitational mass, dominated by dark matter, bends light and creates magnified, distorted images of even more distant
background galaxies.
This sharp infrared Hubble
image illustrates the
case for galaxy cluster Abell 68 as a gravitational telescope, explored by amateur astronomer Nick Rose
during the ESA-Hubble Hidden Treasures image processing competition.
Putting your cursor over the picture will label highlights in the scene. Labels 1 and 2 show two lensed images of the same background galaxy. The distorted galaxy image labeled 2 resembles a vintage space invader!
Label 3 marks a cluster
member galaxy, not gravitationally lensed, stripped of its own gas as it plows
through the denser intergalactic medium.
Label 4 includes many
background galaxies imaged as elongated streaks and arcs. Abell 68 itself is
some 2.1 billion light-years distant toward the constellation
Vulpecula.
Credit: NASA, ESA, Hubble Heritage/ESA-Hubble
Collaboration - Acknowledgment: Nick Rose