Radio Interferometry: Creating Earth-Sized Telescopes

Radio interferometry links multiple radio telescopes to act as one giant instrument.
The technique measures tiny differences in radio waves arriving at each telescope.
Greater distances between telescopes mean sharper resolution—like having a huge “virtual dish.”
The Very Large Array (VLA) in New Mexico is one of the most famous interferometers.
Very Long Baseline Interferometry (VLBI) connects telescopes across continents.
In 2019, the Event Horizon Telescope used VLBI to capture the first image of a black hole.
Interferometry reveals fine details of quasars, pulsars, and star-forming regions.
Networks must synchronize their data with atomic clocks for precision.
Future space-based interferometers could link telescopes in orbit for even greater resolution.
Radio interferometry turns Earth itself into a powerful cosmic observatory.