Smiley from space caused by galaxy cluster and gravitational lens
A smiley face has everybody excited, however scientists say it is no celestial extraterrestrial message but simply the galaxy cluster SDSS J1038+4849 and a bit of gravitational lensing that lined everything up to suggest that some face in deep space was smiling at us.
In the picture, taken by the Hubble Space Telescope, one can make out two orange-coloured eyes and a white button.
The orange eyes are, in fact, two super-bright galaxies, while what appears to be a smiling mouth are really arcs caused by powerful gravitational lensing.
A celestial being smiling down on us? No. Some giant galaxies and gravitational lensing caused the happy face to appeare in deep space. (Image: .spacetelescope.org)
Gravitational lensing occurs when the light from a very bright and distant object is distorted around a massive object such as a gigantic galaxy between the viewer and the bright object. Gravitational lensing was one of Einstein’s predictions in his theory of general relativity.
Galaxy clusters are the largest structures of the Universe. Their gravitational force is so strong that they warp the spacetime around them.
Gravitational lensing distorts light
This super-powerful gravitational force acts as a cosmic lens, which can distort, magnify and bend light.
“In this special case of gravitational lensing, a ring – known as an Einstein Ring – is produced from this bending of light, a consequence of the exact and symmetrical alignment of the source, lens and observer and resulting in the ring-like structure we see here.”
Astrophysicists see the Hubble Space Telescope as a tool to probe these giant galaxies, allowing them to look deeper into the early Universe than every before.
Hubble’s WFC3 (Wide Field Camera 3) and WFPC2 (Wide Field and Planetary Camera 2) studied the “smiley”. It was part of a wider survey of strong lenses.
A version of the smiley image was entered by Judy Schmidt into the Hubble’s Hidden treasures image processing competition.