Over 9 billion years ago, a distant star exploded. Thanks to Einstein, we’ve seen it multiple times on replay.
All across the Universe, matter and energy curve the fabric of space, with dramatic consequences.
Masses are most concentrated in quasars, large individual galaxies, and enormous galaxy clusters.
With enough mass, sufficiently distorted space causes light to travel along multiple paths, arriving at the same destination.
These masses behave as gravitational lenses, creating multiple stretched, magnified images of background stars and galaxies.
When the lens and a background source align in a particular fashion, quadruple images will result.
With slightly different light-travel paths, the brightness and arrival time of each image is unique.
In November 2014, a quadruply-lensed supernova was observed, showcasing exactly this type of alignment.
Although a single galaxy caused the quadruple image, that galaxy was part of a huge galaxy cluster, exhibiting its own strong lensing effects.
Elsewhere in the cluster, two additional images of the same galaxy also appear.
According to Einstein’s General Relativity, one image should have shown a supernova in 1995, the other should appear in late 2015 or early 2016.
On December 11, 2015, that predicted supernova appeared and was quickly discovered.
The combination of this gravitational lens, dark matter, and General Relativity confirms our modern picture of the Universe.
Mostly Mute Monday tells the astronomical story of an object, phenomenon or event in images, visuals, and no more than 200 words. Talk less; smile more.Ethan Siegel is the author of Beyond the Galaxy and Treknology. You can pre-order his third book, currently in development: the Encyclopaedia Cosmologica.