What is LOw-Frequency ARray (LOFAR)?

About LOw-Frequency ARray (LOFAR):

• It is a highly innovative, pan-European distributed radio interferometer and the first of its kind.
• It observes the Universe at low radio frequencies, close to the FM radio band, from 90 to 200 MHz. 
• It was developed by the Dutch Institute for Radio Astronomy (ASTRON) with the goal of exploring the early, distant universe, solar activity, and the terrestrial atmosphere.
• LOFAR can observe in several directions simultaneously, which allows for a multi-user operation. 
• For this reason, LOFAR is novel in its design because it is the first telescope that can look at the entire sky at the same time, unlike other telescopes which you have to point. 
• LOFAR does not have moving parts; steering and tracking across the sky are achieved by treating the signal from the individual antennas in each station with advanced digital beam-forming techniques that make the system agile, allowing for rapid repointing of the telescope as well as giving the potential for multiple simultaneous observations in different directions.
• The LOFAR main coreis based in the north of the Netherlands, with other stations located in France, Germany, and the United Kingdom.

What are Radio Galaxies?

• Radio Galaxies, also known as radio-luminous galaxies or radio-loud galaxies, are a particular type of active galaxy that emits more light at radio wavelengths than at visible wavelengths.
• These happen through the interaction between charged particles and strong magnetic fields related to supermassive black holes at the galaxies’ center.
• They are driven by non-thermal emissions.
• They are much bigger than most of the other galaxies in the universe. 
• The first radio galaxy to be discovered, and still the brightest, is called Cygnus A.

Q1: What are black holes?

A black hole is a region in space where gravity pulls so much that even light can not get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying. Because no light can get out, it is difficult to detect a black hole. The largest black holes are called "supermassive." These black holes have masses that are more than 1 million suns together. Albert Einstein first predicted the existence of black holes in 1916, with his general theory of relativity.

Source: Astronomers discover new radio galaxy using LOw-Frequency ARray (LOFAR)