Mercury stations retrograde on February 21, 1921 at 17° Pisces, and direct on March 16 at 3° Pisces — 23 days. From the Earth, Mercury seems to back up against the stars as we overtake it, as a car passed on the highway seems to slide backward. Astrology holds it a time for crossed wires and delays. Computed from JPL's approximate orbits; the stations agree with an almanac's to within minutes.