Health Editor’s Note: Gravitational Lensing in Action
Behold Hubble’s Best Image of a Distant Galaxy Yet
By Jason Daley Smithsonian.com
To peer through a telescope is to look back in time. The light reaching the lens has taken millions or even billions of years to travel through the vastness of space, which means every image is a snapshot of the distant past. And NASA’s Hubble Space Telescope is a glorious time traveler, spotting galaxies over 13 billion years old that formed around when the universe began.
These distant galaxies often appear rather fuzzy. But now, thanks to a trick of gravity, the space telescope captured an exceptionally detailed image of galaxy that existed 13.3 billion years ago, just 500 million years after the Big Bang, reports Paul Rincon at the BBC.
The impressive detail in the new image of the galaxy is due to a process called gravitational lensing. A massive object, like a large galaxy, can bend space and cause the images of objects behind them to appear brighter and warp them into slightly larger shapes, according to a NASA press release. In this case, a massive galaxy cluster in the foreground of an image amplified the light from a very distant ancient galaxy and smeared it into a small arc.