Black Hole Imaging with the Event Horizon Telescope
The Event Horizon Telescope (EHT) has captured the first image of the shadow of a black hole, a result of the processing and interpretation of petabytes of signal data recorded simultaneously at several locations spanning the globe using the technique of very long baseline interferometry. The radio image, taken at a wavelength of 1.3 mm, matches that of lensed photons from relativistic magnetized plasma surrounding a 6.5 billion solar mass black hole at the center of nearby galaxy M87. I will introduce the EHT instrument and first results, highlighting the challenges in maintaining a phase stable synthetic aperture the size of the Earth at these high radio frequencies. Moving to even higher observing frequencies and and utilizing longer baselines to space places even stronger requirements on timing and calibration, but the additional coverage and resolution provided will enable an entirely new way to study black hole dynamics and populations through direct imaging and movie making.