The known universe has just become much bigger.
A new map of the night sky, published on Tuesday, revealed hundreds of thousands of previously unknown galaxies using a telescope that can detect optical light sources.
The international team behind the unprecedented space survey said that their discovery literally sheds new light on some of the deepest secrets of the universe, including the physics of black holes and how clusters of galaxies are evolving.
"This is a new window on the universe," Cyril Tasse, an astronomer from the Paris Observatory who was involved in the project, told AFP.
"When we saw the first photo, we were: & # 39; What is this?! & # 39; It did not seem at all like what we are used to seeing. & # 39;
More than 200 astronomers from 18 countries were involved in the study, using radio astronomy to look at part of the sky over the northern hemisphere and 300,000 previously invisible light sources that were considered distant galaxies.
Radio astronomy enables scientists to detect radiation that is produced when enormous celestial objects influence each other.
The team used the Low Frequency Array (LOFAR) telescope in the Netherlands to pick up traces – or "rays" – of old radiation that is produced when galaxies flow together. These jets, previously unnoticed, can stretch over millions of light years.
"With radio observations, we can detect radiation from the thin medium that exists between galaxies," said Amanda Wilber of the University of Hamburg.
"LOFAR allows us to detect many more of these sources and to understand what provides them with power."
The discovery of the new light sources can also help scientists better understand the behavior of one of the most enigmatic phenomena of space.
Black holes – which have a gravity that is so strong that they can not escape – emit radiation when they flood over other objects with high mass, such as stars and gas clouds.
Tasse said that the new observation technique would allow astronomers to compare black holes in time to see how they form and develop.
"When you look at an active black hole, the rays (of radiation) disappear after millions of years and you do not see them at a higher frequency (of light)," he said.
"But with a lower frequency they continue to emit these rays for hundreds of millions of years, so we can see many older electrons."
& Universities & # 39; s oldest objects & # 39;
The Hubble telescope has produced images that make scientists believe that there are more than 100 billion galaxies in the universe, although many are too old and distant to be observed using traditional detection techniques.
The map made by the LOFAR observations, part of which was published in the journal Astronomy & Astrophysics, contains data equal to ten million DVDs and shows only two percent of the sky.
The LOFAR telescope consists of a Europe-wide network of radio antenna in seven countries, making it the equivalent of a satellite dish with a diameter of 1 300 km.
The team is planning to make high-resolution images of the entire northern sky, which they say will reveal as many as 15 million previously undiscovered radio sources.
"The oldest objects in the universe are about 11-12 billion light years old," said Tasse. "So we are going to see many more of these objects."
– FOLLOW News24 on Twitter