A radio astronomy technique that combines signals from telescopes separated by thousands of kilometers across continents or even space to achieve extremely high angular resolution. The baseline distance between telescopes determines the resolution, with longer baselines providing sharper images.
An extension of 'interferometry' with 'very long baseline' added in the 1960s when radio astronomers began linking telescopes across continents. 'Baseline' comes from surveying terminology for the fundamental measurement line between two points, adapted to describe the separation between telescope pairs in an interferometric array.
VLBI can achieve resolution so incredible that it could theoretically read the date on a coin sitting on the Moon's surface! This technique doesn't just study space - it's also used to measure continental drift with millimeter precision and helped prove that Earth's rotation is gradually slowing down due to tidal friction.
Complete word intelligence in one call. Free tier — 50 lookups/day.