- The Hubble telescope has taken an image of a galaxy from 13 billion years ago
- Most galaxies from this far away are only observed as a tiny red dot
- The image of this ancient star system has been amplified by gravitational lensing
- A cluster of galaxies between the telescope and the ancient galaxy magnified the image
The Hubble telescope has captured an incredible image of a galaxy almost as old as the universe itself.
The embryonic galaxy, which was in existence just 500 million years after the Big Bang, is at the very limit of what the telescope can observe.
The picture captured by Nasa was magnified by a natural phenomenon known as ‘gravitational lensing’ giving never-before-seen detail of this ancient star system.
The Hubble telescope has captured an incredible image of a galaxy almost as old as the universe itself. Galaxies of this distance are normally only seen as a tiny red dot
WHAT IS GRAVITATIONAL LENSING?
Gravitational lensing occurs when a massive galaxy or cluster of galaxies bend the light emitted from a more distant galaxy.
This forms a highly magnified, though much distorted image.
This is because massive objects bend the spacetime around them, making light travel in a different path.
This theory was first proposed by Einstein in his theory of General Relativity.
In this case a cluster of galaxies called SPT-CL J0615-5746 amplifies the image out, allowing Hubble to see it in new detail.
The universe is thought to be around 14 billion years old and the galaxy photographed by Hubble is thought to be at least 13 billion years old.
That makes this embryonic galaxy – called SPT0615-JD – one of the first to ever be formed after the big bang.
Other galaxies that have been spotted from the infancy of the universe are so distant they only show up as tiny red dots.
However, this galaxy can be seen in far greater detail than others due to a rare celestial phenomenon called gravitational lensing.
‘Pretty much every galaxy at that distance is an unresolved dot… it’s kind of a matter of luck to get a galaxy that’s lensed in just the right way to stretch it out and get that much detail – it’s a pretty nice find,’ the study’s lead author Brett Salmon told BBC News.
The universe is thought to be around 14 billion years old and the galaxy photographed by Hubble is thought to be between 13 and 14 billion years old. That makes this embryonic galaxy – called SPT0615-JD – one of the oldest to ever be formed (file image)
Nasa says gravitational lensing happens when an object with a strong gravitational field is between the object (the galaxy) and the observer (the Hubble telescope).
This huge gravitational field acts as a magnifying glass.
In this case a cluster of galaxies called SPT-CL J0615-5746 amplifies the image out and allows Hubble to see new detail.
‘The lens is not unlike the bottom of a wine glass, distorting that background image,’ said Dr Salmon.
Gravitational lensing (artist’s impression) happens when an object, with a strong gravitational field, is between the object (the galaxy) and the observer (the Hubble telescope)
This image from the early epoch of the universe is a small galaxy, no more than 3 billion solar masses (roughly 1/100th the mass of our fully grown Milky Way galaxy).
We see the galaxy as it was 13 billion years ago because the time taken for light to traverse the vast expanse in-between is so great.
It is less than 2,500 light-years across, which is about 100,000 light years in diameter.
The new findings were presented at the American Astronomical Society meeting in Washington.
The Hubble telescope was launched on April 24, 1990, via the space shuttle Discovery from Kennedy Space Centre in Florida.
It is named after famed astronomer Edwin Hubble who was born in Missouri in 1889.
He is arguably most famous for discovering that the universe is expanding and the rate at which is does so – now coined the Hubble constant.
Hubble has made more than 1.3 million observations since its mission began in 1990 and helped publish more than 15,000 scientific papers.
The Hubble telescope is named after Edwin Hubble who was responsible for coming up with the Hubble constant and is one of the greatest astronomers of all-time
It orbits Earth at a speed of about 17,000 mph in low Earth orbit at about 340 miles in altitude.
Hubble has the pointing accuracy of .007 arc seconds, which is like being able to shine a laser beam focused on Franklin D. Roosevelt’s head on a dime roughly 200 miles away.
Hubble’s primary mirror is 2.4 meters (7 feet, 10.5 inches) across and in total is 13.3 meters (43.5 feet) long – the length of a large school bus.