what is the purpose of the event horizon telescope
Event Horizon Telescope The Event Horizon Telescope (EHT) is a project to create a large telescope array consisting of a global network of radio telescopes and combining data from several very-long-baseline interferometry (VLBI) stations around the Earth. The aim is to observe the immediate environment of the Milky Way's supermassive black hole Sagittarius A*, as well as the even larger black hole in Messier 87, with angular resolution comparable to the black hole's event horizon.[1][2][3][4][5]
Quasar More than 200,000 quasars are known, most from the Sloan Digital Sky Survey. All observed quasar spectra have redshifts between 0.056 and 7.085. Applying Hubble's law to these redshifts, it can be shown that they are between 600 million[39] and 28.85 billion light-years away (in terms of comoving distance). Because of the great distances to the farthest quasars and the finite velocity of light, they and their surrounding space appear as they existed in the very early universe.