These images are not only gorgeous, but they reveal in unprecedented detail the inner workings of these giant cosmic objects, giving us a new perspective on how galaxies work in general.
Using data from the Low Frequency Array (LOFAR), a radio telescope operating at frequencies between 10 and 240 MHz and consisting of 52 stations spread across Europe, astronomers have observed radio galaxy 4C 43.15, quasar 3C 293 and the supergiant elliptical galaxy. Hercules A and gravitational lenses MG 0751 + 2716 and CLASS B1600 + 434.
The LOFAR network captures images at FM radio frequencies that, unlike shorter wavelength sources such as visible light, are not blocked by clouds of dust and gas that can cover astronomical objects.
“We can now investigate the small-scale structure of radio jets at low frequencies, something that was simply not possible before LOFAR international baselines were available,” says Jeremy Harwood, an astronomer at the University of Hertfordshire. “This is an important step forward in understanding how these jets and the galaxies that host them evolve over cosmic time and how the Universe came to be the way we observe it today.”
To give us an idea of the complexity of these snapshots, to produce a single image, more than 13 Terabits of raw data must be digitized per second, transported to a central processor, and then combined. “To process such huge volumes of data we have to use supercomputers,” explains Frits Sweijen, an astronomer at the University of Leiden. “These allow us to transform the terabytes of information from these antennas into just a few gigabytes of science-ready data, in just a couple of days.”
The findings have been published in a special issue of Astronomy & Astrophysics.
