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"EINSTEIN RING SPOTTED BY HUBBLE"

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This image, taken with the Hubble Space Telescope,
shows a distant galaxy located in the constellation

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Fornax. It is the largest and one of the most
complete Einstein rings ever discovered.

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This object’s unusual shape is the result
of gravitational lensing. Albert Einstein,

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in his general theory of relativity, first
theorised that a large gravitational field

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could act as a lens.

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A huge amount of matter, like a cluster of
galaxies, creates a gravitational field that

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distorts and magnifies the light from distant
galaxies that are behind it, but in the same

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line of sight. The effect is like looking
through a giant magnifying glass.

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In this case, the light from the background
galaxy was distorted into the curve we see

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by the gravity of the galaxy cluster sitting
in front of it. The near exact alignment of

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the background galaxy with the central elliptical
galaxy of the cluster, seen in the middle

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of this image, has warped and magnified the
image of the background galaxy around itself

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into an almost perfect ring.

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To get this clear an image of the far-distant
galaxy on its own, Hubble’s 8-foot primary

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mirror would have to have a diameter of 157
feet.

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Objects like these allow us to research galaxies
that would otherwise be too faint and distant

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to see in such detail, helping us learn more
about our amazing universe!

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[ MUSIC ]