The Hubble Space Telescope finds an ‘Einstein Ring’
This is truly spectacular. From NASA and ESA. comes this photo taken by the Hubble Space Telescope which clearly proves on of Einstein’s theories – gravitational lensing.
The bending of light by a gravitational body was predicted by Albert Einstein in 1912, a few years before the publication of general relativity in 1916 (Renn et al. 1997). The ring effect was first mentioned in academic literature by Orest Chwolson in 1924. Einstein remarked upon this effect in 1936 in a paper prompted by a letter by a Czech engineer, R W Mandl, but stated,
Of course, there is no hope of observing this phenomenon directly. First, we shall scarcely ever approach closely enough to such a central line. Second, the angle β will defy the resolving power of our instruments.
Science vol 84 p 506 1936
Now there is.
These graceful arcs are examples of a cosmic phenomenon known as an Einstein ring. The ring is created as the light from a distant objects, like galaxies, pass by an extremely large mass, like this galaxy cluster. In this image, the light from a background galaxy is diverted and distorted around the massive intervening cluster and forced to travel along many different light paths toward Earth, making it seem as though the galaxy is in several places at once.
This image from Hubble is packed full of galaxies. A keen eye can spot exquisite elliptical galaxies and spectacular spirals, seen at various orientations: edge-on with the plane of the galaxy visible, face-on to show off magnificent spiral arms, and everything in between.The vast majority of these specks are galaxies, but to spot a foreground star from our own galaxy, you can look for a point of light with tell-tale diffraction spikes. The most alluring subject sits at the centre of the frame. With the charming name of SDSSJ0146-0929, the glowing central bulge is a galaxy cluster — a monstrous collection of hundreds of galaxies all shackled together in the unyielding grip of gravity.
With the charming name of SDSS J0146-0929, this is a galaxy cluster — a monstrous collection of hundreds of galaxies all shackled together in the unyielding grip of gravity. The mass of this galaxy cluster is large enough to severely distort the space-time around it, creating the odd, looping curves that almost encircle the center of the cluster.
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