Chiron

Charles Kowal found Chiron on 1 November 1977. Its astrological meaning was written within a dozen years: Barbara Hand Clow's Chiron came out in 1987, Melanie Reinhart's Chiron and the Healing Journey in 1989.

Charles Kowal's discovery of Chiron (1 November 1977); Barbara Hand Clow, Chiron (1987); Melanie Reinhart, Chiron and the Healing Journey (1989); The Astrology Podcast, episode 271 (2020)

Small body orbiting between Saturn and Uranus, found in 1977, read by astrologers as the 'wounded healer'.

Sources3 sources

Primary source

Apollodorus; J. G. Frazer (trans.), The Library, 1921, 2.5.4The centaur Chiron's incurable wound from Heracles' arrow.
But the hurt proving incurable, Chiron retired to the cave and there he wished to die
Apollodorus; J. G. Frazer (trans.), The Library, 1921, 3.10.3Chiron as teacher of healing to Asclepius.
by whom he was brought up and taught the arts of healing and hunting

Where this claim originates

Chris Brennan with Melanie Reinhart, The Astrology of Chiron, The Astrology Podcast, episode 271, 2020, Show notesReinhart's Chiron and the Healing Journey first appeared in 1989; the show notes also date Clow's book to 1987 and Kowal's discovery to 1 November 1977.
which was originally published in 1989