Physics Department Colloquium: Tuesday, March 3, 2020 -- The Event Horizon Telescope: Imaging a Black Hole

Event Date: 

Tuesday, March 3, 2020 - 3:45pm

Event Date Details: 

Refreshments served at 3:30pm.

Event Location: 

  • Broida 1640
  • Physics Department Colloquium

The Event Horizon Telescope (EHT) is a Very Long Baseline Interferometry (VLBI) array operating at the shortest possible wavelengths, which can resolve the event horizons of the nearest supermassive black holes. Observing at mm radio wavelengths enables detection of photons that originate from deep within the gravitational potential well of the black hole and travel unimpeded to telescopes on the Earth. The primary goal of the EHT is to resolve and image the predicted ring of emission formed by the photon orbit of a black hole and to eventually track dynamics of matter as it orbits close to the event horizon. A sustained program of improvements to VLBI instrumentation and the addition of new sites through an international collaborative effort led to Global observations in April 2017: the first campaign with the potential for horizon imaging. After two years of data reduction and analysis we reported success on April 10th, 2019: we have imaged a black hole. The resulting image is an irregular but clear bright ring, whose size and shape agree closely with the expected lensed photon orbit of a 6.5 billion solar mass black hole. This talk will cover the project background and first results as well as future directions for a next- generation instrument that is aimed at real-time black hole video.

Shep Doeleman, Harvard University