A Newly Discovered ‘Einstein’s Cross’ Reveals the Existence of a Giant Dark Matter Halo

According to Einstein’s general theory of relativity, light bends around objects with large masses, such as galaxies. This sometimes causes a phenomenon known as gravitational lensing, which brightens, magnifies, and distorts light from objects behind.

In rare cases, a gravitational lens can even split light passing through it and make it appear multiple times. Such a phenomenon is called an “Einstein’s cross” due to the shape that these split repetitions of light form.

The Einstein’s cross G2237+0305 observed in September 1990 by the Hubble Space Telescope.

PHOTOGRAPH: NASA, ESA, AND STSCI

A new Einstein’s cross has recently been observed and described in a scientific paper. The discovery was made by a research team from the Atacama Large Millimeter/Submillimeter Array (ALMA), a space telescope located in northern Chile, using observation data from ALMA and other telescopes. The light of the cross comes from HerS-3, a galaxy located 11.6 billion light years away, with the gravitational lensing being generated by four giant galaxies located between HerS-3 and the Earth. These giant galaxies are located some 7.8 billion light years away.