The thrice-visible galaxy is a little tricky to spot: it appears three times around the star, once as a curved arc and twice as small spherical dots.
Hubble’s Wide Field Camera 3 (WFC3) captured this image of stars and galaxies using data collected for scientific purposes.
The object of interest was SGAS 0033+02, a galaxy seen in the bottom right corner of the photograph.
What makes this galaxy unique is that it appears not once, but three times in this image. The thrice-visible galaxy is a little tricky to spot: it appears three times around the star, once as a curved arc and twice as small spherical dots.
The repeated appearances of SGAS 0033+02 in the same image are not due to an error, but rather to gravitational lensing, fascinating phenomena.
When the light from a very distant galaxy, such as SGAS 0033+02, is bent (or ‘lensed’) by the gravity of a huge astronomical object in the foreground, between the distant galaxy and the Earth, gravitational lensing occurs.
The Sloan Giant Arcs Survey (SGAS), which aimed to locate extremely magnified galaxies that were gravitationally lensed by foreground galaxy clusters, identified SGAS 0033+02.
Because of its remarkable proximity in the sky to a very bright star, SGAS 0033+02 is of particular interest. Because it may be used to calibrate and correct observations of the lensed SGAS 0033+02, the star is helpful.
Source: ESA/Hubble & NASA, E. Wuyts
Image Credit: Getty
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