Lintott et al. proposed that Hanny's Voorwerp represents the first observation of a "light echo" from one of these objects, which is thought to have ejected matter from the adjacent IC 2497.
Lintott et al. proposed that Hanny's Voorwerp represents the first observation of a "light echo" from one of these objects, which is thought to have ejected matter from the adjacent IC 2497. Examples of these objects that are older than the re-ionization epoch are seen through an intervening medium that is largely neutral hydrogen, in contrast to more recent examples of these objects that display a (*) Lyman Alpha Forest. The fact that the luminosity of these objects varies on a timescale of weeks or months combined with the fact that they shine continuously implies that they are powered by the gravitational energy of matter accreting onto super-massive black holes. For 10 points, name these distant active galactic nuclei whose name derives from their extremely high energy output in combination with a point-like emission spectrum.
Lintott et al. proposed that Hanny's Voorwerp represents the first observation of a "light echo" from one of these objects, which is thought to have ejected matter from the adjacent IC 2497.
quasars (prompt on "active galactic nuclei" before mention)