The Hubble Space Telescope recently captured an image which looks remarkably like a smiling face in the sky. It is SDSS J1038+4849, a galaxy cluster that resides just outside the constellation of Ursa Major. But what makes this image look so close to a smiley face?
Since 1990, Hubble has taken over a million pictures of the cosmos–quite a vast archive of images. The photo above contains a collection of galaxies and galactic clusters. The first thing you’ll notice in the image is how a piece of it resembles the shape of a smiley face.
The two bright eyes in the face are actually two distant galaxies. The curving lines that make up the roundness of the face are actually created in an effect called “strong gravitational lensing.”
Galaxy clusters are some of the most massive structures in the universe. They can exert a gravitational pull so strong that it warps the space-time that surrounds them. What you’re seeing is a galaxy cluster in the foreground acting like a lens that bends and distorts the light source in the background in a display known as an Einstein Ring. It is the result of an exact, symmetrical alignment of the light source, the galactic lens, and the person observing it.
Strong gravitational lensing is an important part of the Hubble Space Telescope’s discoveries as it helps provide a sneak peak into the early universe. This smiley face object was viewed via Hubble’s Wide Field and Planetary Camera 2 and Wield Field Camera 3.