These peculiar bright blue arcs imaged by the Hubble Space Telescope are a remarkable example of a natural phenomenon called gravitational lensing.

The cluster of orangey galaxies at the centre of the picture have caused nearby space to act like a powerful telescope itself, magnifying a much more distant galaxy and wildly stretching its light.

The cluster, labelled RCS2 032727-132623, lies in the foreground yet is still five billion light-years away from us. Incredibly, the bright and distorted object lies twice that distance at nearly ten billion light-years.

Though the colour photo has only just been released by the Hubble team, it was taken with the space telescope's Wide Field Camera 3 (WFC3) in March last year.

Astronomers are hailing it as the brightest naturally magnified galaxy discovered so far in the Universe, and about three times brighter than any previously known. Thanks to the natural lens, it is allowing them to study in "close-up" a galaxy that was actively churning out stars when the Universe was just a third the age it is today. That will help them learn how galaxies have evolved over the last ten billion years.

Jane Rigby, of NASA's Goddard Space Flight Center in Maryland, led the team that used Hubble to capture the nearly 90-degree arc of light. Their results will be published in The Astrophysical Journal.

Such a distant galaxy would usually have appeared as a tiny faint blob, even with Hubble. Thanks to the cluster's ensing effect, it appears several times around them in its larger but distorted form. The astronomers were able to remove the distortions and reconstruct the galaxy, so revealing its bright regions of star formation.