قالب وردپرس درنا توس
Home / Science / New sky survey shows hundreds of thousands of galaxies

New sky survey shows hundreds of thousands of galaxies



More than 200 astronomers in 18 countries created a Radio Sky Survey using the Low Frequency Array Telescope (LOFAR). The first phase of this major survey was published this week along with 26 research papers in the journal Astronomy & Astrophysics.

LOFAR is a very sensitive radio survey that shows the sky with fine details. It is operated by ASTRON, the Netherlands Institute of Radio Astronomy. In the first phase, LOFAR used low radio frequencies to observe about a quarter of the northern hemisphere's sky.

Radio astronomy is another way to uncover the secrets of the universe that optical light can not.

The radio signals from 300,000 sources appeared, almost all galaxies. However, the researchers were also able to see black holes, observe the evolution of galaxy clusters, and measure magnetic fields.

  Farewell to Opportunity, Surprising Fossil Findings and a Space Pancake: This Week in Space and Science

Astronomers hope to use LOFAR to pinpoint where the black holes are coming from by looking at the material jets they release, which is seen at radio wavelengths.

"LOFAR has a remarkable sensitivity and lets us realize that these jets are present in all massive galaxies, which means that their black holes never stop eating," said Philip Best, one of the authors of the study and professor of the study The School of Physics and Astronomy of the University of Edinburgh in a statement.

Galaxy clusters look like a mass of stars, but are actually groupings of hundreds or even thousands of galaxies. Sometimes two galaxies merge, resulting in radio emissions that can range to millions of light-years, most likely due to particles being accelerated by fusion.

Radio observations make it possible for astronomers to recognize this radiation caused by an energetic shock and to understand how it was formed, says Amanda Wilber, PhD student at the University of Hamburg. But it is also illuminated something else.

  NASA's Newest Mission Will Investigate the Origins of the Universe

What we're going to see with LOFAR is that in some cases galaxy clusters that do not fuse together can show this emission, albeit at a very low level that was previously undetectable. This discovery tells us that besides fusion events there are other phenomena that can trigger particle acceleration across large scales, "Annalisa Bonafede, professor at the Faculty of Physics and Astronomy at the University of Bologna, said in a statement.

With LOFAR astronomers can also measure weak magnetic fields in space 19659003] "The unprecedented accuracy of LOFAR measurements has allowed us to measure the impact of cosmic magnetic fields on radio waves from a giant radio galaxy of 11 million light-years in size. This work shows how we can use LOFAR to help us and he understands the origin of the cosmic magnetic fields, "said Shane O'Sullivan, a professor at the University of Hamburg, in a statement.

  These are the first massive ones black holes from the early universe

But the actual process of generating the beautiful images of these distant galaxies requires data not just time, but also strength LOFAR collects so much data that scientists had to process about 10 million DVDs in value.

They were able to use the supercomputer and data center of SURF, the Dutch information and communication technology organization. to process the record in a year – something that would have taken centuries on a normal computer.

"These pictures are now public and will allow astronomers to study the evolution of galaxies in unprecedented detail, "said Timothy Shimwell, an ASTRON employee in a statement.

The 26 papers released this week include only the first 2% of the Sky survey. Finally, the team hopes to have pictures of the entire northern sky, which would contain 15 million radio sources. The researchers believe that these signals will reveal the first massive black holes that have formed during the childhood of the universe.


Source link