Hubble uses cosmic optical illusion to spy a quasar 17 billion light-years away

By Georgina Torbet August 29, 2021

This week’s image from the Hubble Space Telescope shows a kind of optical illusion that is helping researchers to peer out even deeper into the depths of our universe. Using a phenomenon called gravitational lensing, Hubble captured this image which seems to show four bright points of galaxies forming a ring around an even brighter central pair.

But despite how it appears, there aren’t six galaxies represented in the center of this image — there are actually two galaxies and one very, very distant quasar, which is an extremely bright center of a galaxy.

Clustered at the center of this image are six brilliant spots of light, four of them creating a circle around a central pair. It is not two separate galaxies and one distant quasar imaged four times. — Clustered at the center of this image are six brilliant spots of light, four of them creating a circle around a central pair. Appearances can be deceiving, however, as this formation is not composed of six individual galaxies, but is actually two separate galaxies and one distant quasar imaged four times. ESA/Hubble & NASA, T. Treu; Acknowledgment: J. Schmidt

This effect happens because the two galaxies, which are closer to us, act like a magnifying glass on the quasar called 2M1310-1714, which is farther away at approximately 17 billion light-years distance from us. The galaxies have so much mass that their gravity bends the rays of light coming from the quasar, making the quasar more clearly visible to us.

It is this bending that makes it appear that there are four points of light surrounding the pair of galaxies when in reality there is actually just one quasar, the light from which is warped to make it look like four light sources.

Gravitational lensing may be visually confusing, but it can be a powerful tool for examining distant objects. It allows researchers to see farther out and could even be used to study the mysterious phenomenon of dark matter. A variation on this technique, called microlensing, will be used by the upcoming Nancy Grace Roman Space Telescope to detect distant exoplanets by seeing the way light bends when one star passes in front of another.

Editors' Recommendations

Topics

Georgina Torbet

Space Writer

Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…

Space

Hubble captures an elegant spiral galaxy 60 million light-years away

A stunning view of the spiral galaxy NGC 4571.

This week's image from the Hubble Space Telescope shows the spiral galaxy NGC 4571, located 60 million light-years away in the constellation of Coma Berenices, and was captured using Hubble's Wide Field Camera 3 instrument.

This cosmic portrait – captured with the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 – shows a stunning view of the spiral galaxy NGC 4571, which lies approximately 60 million light-years from Earth in the constellation Coma Berenices. This constellation – whose name translates as Bernice’s Hair – was named after an Egyptian queen who lived more than 2,200 years ago. ESA/Hubble & NASA, J. Lee and the PHANGS-HST Team

Space

Hubble images two galaxies aligned but light-years apart

The twin galaxies NGC 4496A and NGC 4496B dominate the frame in this image from the NASA/ESA Hubble Space Telescope. Both galaxies lie in the constellation Virgo, but despite appearing side-by-side in this image they are at vastly different distances from both Earth and one another. NGC 4496A is 47 million light-years from Earth while NGC 4496B is 212 million light-years away. The enormous distances between the two galaxies mean that the two are not interacting, and only appear to overlap because of a chance alignment.

This week's image shared by the team from the Hubble Space Telescope shows two galaxies that appear to be overlapping. But unlike last week's Hubble image, which showed two galaxies interacting, this week's image shows two galaxies that are actually light-years apart.

The two galaxies here are NGC 4496A, which is 47 million light-years from Earth, and NGC 4496B, which is much further away at 212 million light-years distance. The two happen to be aligned so they appear to be overlapping because they are both in the same direction from Earth, but they do not actually interact at all.

Space

Mystery of a strange, mirrored double galaxy solved using Hubble data

hubble mirrored galaxy stsci 01ffjer4zps9v9yfpbhrb7p5wj 1

When telescopes like Hubble peer out into the cosmos, they can sometimes sneak a view of very distant objects using a phenomenon called gravitational lensing. This is where a massive object like a galaxy passes between a distant object and Earth, and the gravity of this intermediate object warps spacetime and acts as a magnifying glass. This allows astronomers to glimpse objects which would otherwise be too faint and far away to be visible.

But sometimes these phenomena result in strange outcomes, like an oddity spotted by Hubble in 2013 which appeared to be two objects that were perfect mirror images of each other.