What is a blazar?
Q: What is a blazar?
A: A blazar is a very compact quasar with a supermassive black hole at the center of an active, giant elliptical galaxy that is among the most energetic phenomena in the universe.
Q: What is an active galactic nucleus (AGN)?
A: An active galactic nucleus (AGN) is a region at the centre of a galaxy which has a much higher than normal luminosity over some or all of the electromagnetic spectrum.
Q: What is the difference between a blazar and other active galaxies that host AGN?
A: Blazars are among a group of active galaxies that host AGN, but they have a relativistic jet that is pointing in the general direction of the Earth, making them easier to observe.
Q: Who coined the term "blazar"?
A: The term "blazar" was coined in 1978 by astronomer Edward Spiegel.
Q: Why do many blazars have apparent superluminal features within the first few parsecs of their jets?
A: Many blazars have apparent superluminal features within the first few parsecs of their jets, probably due to relativistic shock fronts.
Q: What fuels the blazar at the center of galaxy M87?
A: The blazar at the centre of galaxy M87 is fuelled by a black hole with a mass of about three billion solar masses within ten light years of the galaxy centre.
Q: Why are blazars an important topic in astronomy?
A: Blazars are among the most energetic phenomena in the universe and are an important topic in astronomy because they provide insights into high-energy astrophysical processes and the evolution of galaxies.
