Astronomers have discovered a galaxy with the giant Atacama Large Millimeter Array (ALMA) telescope that is very similar to the Milky Way. It lies at such an enormous distance, it took more than 12 billion years for light to reach Earth, that it offers astronomers a unique opportunity to study a young, similar galaxy.
The acquired images date from the time when the universe was 'only' about 1.4 billion years old, 10 percent of the current age. The galaxy has been named SPT0418-47.
When a discovery is at such a great distance, astronomers have great difficulty seeing more than one tiny black spot on the horizon, even with the largest telescopes.
The team of researchers, which included Filippo Fraternali of the University of Groningen, devised an ingenious trick to 'zoom in' on the system. The astronomers used a nearby galaxy to distort, deflect and further catapult the light, acting as a powerful magnifying glass, as it were.
Through the so-called gravity lens effect, details of 'the young Milky Way' became visible. Due to the distortion of the light, the galaxy stands as a ring of light in the sky, it has been determined that, like the Milky Way, it contains a kind of rotating disc and also has a bulge: a so-called cloud in the center of the galaxy in which large groups of stars have gathered.
The researchers write in the scientific journal Nature that a so-called bulge has never been observed at such an early stage.
'Disk is in an orderly condition and goes against current theories'
The disc is in "orderly condition", according to the researchers. That would contradict traditional theories which hold that galaxies in the early stage of the Universe were unstable and turbulent. Further research with the relatively new Extremely Large Telescope (ELT) of the European Southern Observatory (ESO) should confirm whether the disk is indeed relatively less chaotic.
Research leader Francesca Rizzo speaks of a "breakthrough" in the field of system formation. According to her, the findings show that the structure of the Milky Way was created 12 billion years ago.
Presumably, SPT0418-47 will develop into an elliptical galaxy, another type of galaxy that can be found in the universe along with spiral galaxies.