an astronometric satellite launched in 1989 by the European Space Agency that measured the position, proper motion, and brightness of 118 218 stars down to 12th magnitude and the magnitude and colour of a million stars down to 10th magnitude
[hi-pahr-kuh s] /hɪˈpɑr kəs/ noun 1. died 514 b.c, tyrant of Athens 527–514. 2. c190–c125 b.c, Greek astronomer. /hɪˈpɑːkəs/ noun 1. 2nd century bc, Greek astronomer. He discovered the precession of the equinoxes, calculated the length of the solar year, and developed trigonometry 2. died 514 bc, tyrant of Athens (527–514) /hɪˈpɑːkəs/ noun 1. a […]
[hur-soo-chuh-luh s] /hɜrˈsu tʃə ləs/ adjective 1. .
[hur-tel-uh s] /hɜrˈtɛl əs/ adjective 1. minutely hirsute.
Health Information Research Unit