Public index · Planetary
Psyche’s day
~4.2 h
Measured
Synodic rotation of (16) Psyche
Psyche’s present day is about 4.2 hours. Ferrais 2020 reads the shape as a slowed Jacobi ellipsoid that once spun nearer three hours. Four-point-two is a rounding of a spacecraft-grade period, not 42.
What it supports
A measured asteroid day. NASA: just over four hours. JPL 4.196 h is the same clock. The 4.2 h sits next to this Book’s 4°20′. Two instruments. Not one proof.
What it does not
Not 42. Not the 42″ coordinate. Not density as destiny.
ExactnessApproximate
Form4.2
Unithours
Strengthhard