Scientists from the Cardiff University peer 12 billion years into the past to-reveal distant galaxy with an unexpected-appearance.
Scientists challenged our current understanding about how galaxies form-by unveiling pictures of a young galaxy in the early-life of the Universe which appears surprisingly mature.
The galaxy known as ALESS 073.1, appears to have all of the features expected of a much-more mature galaxy and led the scientists to question, how it grew so fast.
The new research has been published in Science.
Galaxies are in different shapes, sizes & colors and are made from different components like rotating disks, spiral arms & bulges.
A major goal of present-day astronomy is understanding, why different galaxies look the way they’re today & when their different components formed.
The team led-by scientists at the Cardiff University, used the Atacama Large Millimeter Array (ALMA) telescope as a time machine to peer into the remote past, revealing how ALESS 073.1 looked only 1.2 billion years after the Big Bang.
Because light emitted from the galaxy took billions-of-years to reach our telescopes on the Earth, team were able to explore, how the galaxy looked during its infancy & determine how it had been initially formed.
The result was one among the sharpest & direct images of a primordial galaxy ever produced, which allowed team to undertake a detailed study of its internal structure.
“We discovered that a massive bulge, a regular rotating disk & possibly spiral arms were already in place in this galaxy, when the Universe was just 10 percent of its current age,” said lead-author of the study Dr. Federico Lelli, who undertook the work in Cardiff University’s School of Physics & Astronomy.
“In other words, this galaxy seems like a grown adult, but it should be just a little-child.”
Co-author of study Dr. Timothy Davis from School of Physics & Astronomy, said: “This spectacular discovery challenges our current-understanding of how galaxies form, because we believed these features only arose in mature galaxies, not in young-ones.”
One key feature of a galaxy is the presence of a bulge, a tightly packed group of stars usually situated within the center of the galaxy.
It was believed that massive bulges formed slowly-by the merging of small galaxies or by specific processes that occurred within the galaxy itself, however, kinematic properties of ALESS 073.1 revealed that the formation of massive bulges can occur extremely fast, around half the stars in the galaxy were shown to be in a bulge.
Similarly, some mature galaxies like our own Milky Way galaxy are known to have spiral arms extending from their central parts, giving-them a distinctive spiral shape.
Similar features were unexpectedly spotted in ALESS 073.1, much to the team’s amazement as early galaxies are thought to be chaotic & turbulent instead of having regular, well-organized structures like spiral arms.
“A galaxy-like ALESS 073.1, just defies our understanding of galaxy formation,” concluded Dr. Lelli.
