Astronomers used a natural magnifying glass to sharpen the images captured by NASA's Hubble Space Telescope. The improved images unveiled newborn stars in a distant galaxy that formed only 2.7 billion years after the Big Bang.
Gravitational Lensing
Hubble is a powerful telescope, but it has limitations when it comes to peeking into distant universe. To capture more detailed images of a distant galaxy Hubble normally sees as unremarkable, astronomers took advantage of a natural phenomenon and used new computational methods.
The galaxy lies about 11 billion light-years away from the sun and astronomers can see it as it appeared 11 billion years ago, which is just a few billion years after the Big Bang, the event popularly attributed to kickstarting the universe about 13.8 billion years ago.
Hubble would normally capture unremarkable images of this galaxy, but gravitational lensing helped the space telescope produce 10 times sharper images than normal.
Gravitational lensing occurs when light from a more distant galaxy passes a massive object such as another galaxy or an entire galaxy cluster, and is bent and distorted by gravity into an arc.
In these new observations, gravitational lensing magnified the distant disk galaxy dotted with brilliant newborn stars almost 30 times.
Fireworks Image Of Stars
Scientists also developed a new computer code to eliminate distortions and reveal the galaxy as it would normally appear. Astronomers found the reconstructed image similar to that of a fireworks.
"When we saw the reconstructed image we said, 'Wow, it looks like fireworks are going off everywhere,'" said Jane Rigby of NASA's Goddard Space Flight Center.
The new Hubble images revealed two dozen clumps of newborn stars. Each of these stars spans about 200 to 300 light-years across, which contradicts earlier theories that suggest the star-forming regions in the early universe were much larger spanning at least 3,000 light-years in size. The images also revealed other details about the galaxy.
"At the normal spatial resolution of the deep fields, there is no sign of clumpy star formation within SGAS J111020.0+645950.8," the researchers reported in one of the papers that detailed their findings.
"However, the enhanced spatial resolution enabled by gravitational lensing tells a very different story; much of the star formation arises in two dozen clumps with sizes of r = 30-50 pc spread across the 7 kpc length of the galaxy."
The findings were reported in three studies published in The Astrophysical Journal Letters and The Astrophysical Journal.
