Halley

Halley's Comet, named after British scientist Edmund Halley, is a short-period comet that appears every 76 years, with its next appearance in 2061. During its last approach to the Sun, space probes from the USA, Soviet Union, and Japan provided the first close-up observations of a comet.

What significant event occurred during Halley's Comet's last close approach to the Sun?

Which countries sent space probes to Halley's Comet?