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Recordedmonthinfrastructure

The Event Horizon Telescope observes M87* and Sagittarius A*

Over a handful of nights in April 2017 the array observed both targets at 1.3 millimetres, requiring simultaneously usable weather at sites in Chile, Hawaii, Mexico, Arizona, Spain and Antarctica. Petabytes of data were recorded to hard drives and shipped physically to correlators in Massachusetts and Bonn. The South Pole recordings could not be flown out until the austral winter ended, so correlation of the full campaign did not begin until late in the year - one reason the results appeared two years after the observations.

Observed — measured or witnessed, with the observation cited.

Subjects

Evidence

Partly verified — Core facts are sourced; some optional detail is deliberately absent.

Recorded on Event Horizon Telescope

  1. Heber Curtis records a curious straight ray in Messier 87
  2. A mechanism for extracting energy from a spinning black hole
  3. A star is tracked through a complete close approach to the Galactic centre
  4. The Event Horizon Telescope observes M87* and Sagittarius A*
  5. S2 passes pericentre and its light is measurably redshifted
  6. The first image of a black hole shadow is published
  7. The orbit of S2 is shown to precess as general relativity predicts
  8. The Nobel Prize in Physics recognises black holes twice over
  9. The M87* ring is imaged in polarised light
  10. The black hole at the centre of our own galaxy is imaged
  11. A second epoch shows the ring persists and the bright spot moves

Related

Related because they share a subject in the Atlas — never because the text looks similar.