Using data from the Low Frequency Array (LOFAR), a radio telescope that operates at frequencies between 10 and 240 MHz and consists of 52 stations spread across Europe, astronomers observed radio galaxy 4C 43.15, the quasar 3C 293 and the supergiant elliptical galaxy Hercules A as well as gravitational lenses MG 0751+2716 and CLASS B1600+434.
The Universe is flooded with electromagnetic radiation, of which visible light comprises only a tiny slice.
From short-wavelength gamma rays and X-rays to long-wavelength microwaves and radio waves, each part of the light spectrum reveals something unique about the Universe.
The LOFAR network captures images at FM radio frequencies which, unlike shorter wavelength sources like visible light, are not blocked by the dust and gas clouds that can blanket astronomical objects.
Regions of space that appear dark to our eyes actually glow in radio waves, allowing astronomers to peer into star-forming regions or the hearts of galaxies themselves.
New images from the LOFAR telescope network push the boundaries of what astronomers know about galaxies and supermassive black holes.
They reveal the inner workings of galaxies near and far at a resolution 20 times sharper than typical LOFAR images.
“We are now able to study the fine-scale structure of radio jets at low frequencies, which was simply not possible before international LOFAR baselines became available,” said Dr Jeremy Harwood, astronomer at the University of Hertfordshire.
“This is a significant step forward in understanding how these jets and the galaxies that host them evolved over cosmic time and how the Universe came to be as we observe it today. ‘today.”
The relative ease of the experience for the end user belies the complexity of the computational challenge that makes every LOFAR image possible.
To produce a single image, more than 13 terabits of raw data per second must be digitized, transported to a central processor, and then combined.
“To process such immense volumes of data, we need to use supercomputers,” said Dr Frits Sweijen, an astronomer at Leiden University.
“These allow us to turn terabytes of information from these antennas into a few gigabytes of science-ready data, in just a few days.”
A special issue of the scientific journal Astronomy & Astrophysics is devoted to 11 research papers describing the new LOFAR images.