The two giant radio galaxies discovered by the MeerKAT telescope. In the background is the sky as seen … [+]
I. Heywood (Oxford / Rhodes / SARAO)
Astronauts using a giant radio telescope in South Africa have discovered two of the largest single objects in the universe.
About 22 times larger than our Milky Way, these “giant radio galaxies” were found in a small patch of the night sky.
That leads the authors of a new paper published today in the Monthly notices from the Royal Astronomical Society to find out if there are many more of these “cosmic animals” than previously thought.
“We found these large radio galleries in an area of sky that is only about four times the size of the full moon,” said Dr. Jacinta Delhaize, who is a Research Fellow at the University of Cape Town and lead author of the work.
That’s around 1º. The probability of finding two large radio galaxies (GRGs) in such a small area is estimated at less than 0.0003 percent. “This means that large radio galleries seem to be more common than we thought,” Delhaize said.
What is a giant radio galaxy?
It is a giant galaxy about 700 kilo-parsecs in size, or about 22 times larger than the Milky way, and more than 2.28 million light-years long.
Only 831 “giant radio galaxies” are thought.
Most of them are elliptical galleries with large black holes.
GRGs are thought to have existed for several hundred million years, long enough for their radio jets to grow to large sizes.
If that is true, then a lot more GRG ought to identified before this time.
Centaurus A is a well-known example of a relatively nearby radio galaxy. Inside the galaxy is a … [+]
ESO / WFI (Optical); MPIfR / ESO / APEX / A.Weiss et al. (Submillimetre); NASA / CXC / CfA / R.Kraft et al. (X-ray).
How big are these ‘giant radio galaxies’?
MGTC J095959.63 + 024608.6 and MGTC J100016.84 + 015133.0 are much, much larger than “regular” GRGs.
“These two galaxies are unique in that they are among the most recognizable giants, and in the top 10 percent of major radio galleries,” said Dr. Matthew Prescott, Research Fellow at the University of Cape Breton. West and co-author of the work. “They are over two mega-parsecs in diameter, which are about 6.5 million light-years old or about 62 times the size of the Milky Way. But they are weaker than others of the same size. ”
How were these two giant radio galaxies discovered?
They were found in new radio maps of the skies created by the MeerKAT International Gigahertz Tiered Extragalactic Exploration (MIGHTEE) study at the MeerKAT South African radio telescope.
Radio astronomy is the study of celestial objects that emit radio waves to reverse hidden emissions, explosions, and signals. It helps to present the Universe as it really is rather than just how it looks.
South Africa MeerKAT Telescope.
South African Radio Astronomical Observatory (SARAO)
What is a MeerKAT telescope?
Radio telescopes are usually several vessels. Located in the Karoo region of South Africa, the new MeerKAT telescope is made up of 64 radio vessels.
The forerunner of the Square Kilometer Array (SKA) is a radio telescope that covers both South Africa and Australia. When the SKA becomes operational in the mid-2020s, it is hoped that its sensitivity will reveal many more radio galleries – and change our understanding of how galleries grow.
Wishing you clear skies and wide eyes.