Velocity and acceleration of planets 1 by astrojin Hi everybody, I didn't have anything better to do last night, so Icame up with some data of the planetary motions... Apparent Velocities and Accelerations of Planets Definitions: Daily Velocity = the zodiacal position of a planet at any day subtract its zodiacal position of the previous day. Daily Acceleration = the daily velocity of a planet at any day subtract its daily velocity of the previous day. Acceleration is simply another term for rate of velocity. The daily velocities and accelerations are measured relative to earth (geocentric) i.e. their apparent motions. The definitions used for the data collected below: Min velocity = the minimum velocity of the planet between Jan 1 1900 to Dec 31 1999 (100 years duration). Max velocity = the maximum velocity of the planet between Jan 1 1900 to Dec 31 1999 (100 years duration). Average velocity = the average velocity of the planet between Jan 1 1900 to Dec 31 1999 (100 years duration). Min acceleration = the minimum acceleration of the planet between Jan 1 1900 to Dec 31 1999 (100 years duration). Max acceleration = the maximum acceleration of the planet between Jan 1 1900 to Dec 31 1999 (100 years duration). Average acceleration = the average acceleration of the planet between Jan 1 1900 to Dec 31 1999 (100 years duration). All velocities have units on degrees/day All accelerations have units of degrees/day/day Analyses were done for the luminaries and the five traditional planets only. Period considered: 100 years [01 Jan 1900 to 31 Dec 1999] Moon Min Velocity 11d 45m 47 s Max Velocity 15d 23m 02s Average Velocity 13d 10m 36s Min Acceleration -0.5084 Max Acceleration 0.5091 Average Acceleration -0.000055 Mercury Min Velocity -01d 23m 03s Max Velocity 02d 12m 08s Average Velocity 00d 59m 09s Min Acceleration -0.1981 Max Acceleration 0.1953 Average Acceleration 0.000007 Venus Min Velocity -00d 37m 57s Max Velocity 01d 15m 31s Average Velocity 00d 59m 2s Min Acceleration -0.0424 Max Acceleration 0.042 Average Acceleration -0.000001 Sun Min Velocity 00d 57m 10s Max Velocity 01d 01m 12s Average Velocity 00d 59m 8s Min Acceleration -0.0008 Max Acceleration 0.0008 Average Acceleration -0.000000016 Mars Min Velocity -00d 24m 4s Max Velocity 00d 47m 29s Average Velocity 00d 31m 25s Min Acceleration -0.0152 Max Acceleration 0.0143 Average Acceleration 0.000000134 Jupiter Min Velocity -00d 8m 12s Max Velocity 00d 14m 33s Average Velocity 00d 04m 58s Min Acceleration -0.0035 Max Acceleration 0.0036 Average Acceleration -0.0000044 Saturn Min Velocity -00d 04m 58s Max Velocity 00d 07m 49s Average Velocity 00d 01m 59.55s Min Acceleration -0.002 Max Acceleration 0.002 Average Acceleration 0.0000038 - Greatest elongation: Sun-Mercury = 27 degrees 47 min Sun-Venus = 47 degrees 15 min Percentage Retrograde (from 01 Jan 1900 to 31 Dec 1999): Mercury = 19.1% Venus = 7.3% Mars = 9.5% Jupiter = 30.4% Saturn = 36.6% Notes 1. The luminaries (sun and moon) can never have zero velocities for the same reason that they can never be in retrograde motion (i.e. their velocities are always positive). Hence, the values of minimum velocities given above are their slowest velocities. 2. For a planet (any of the five traditional planets), it can have zero velocity (when it is apparently stationary with respect to earth). Hence, the minimum velocity (always a negative value) shown is actually the maximum velocity of the planet when it is in retrograde motion. 3. When a planet?s velocity is zero, the planet is stationary. 4. When a planet?s velocity is positive, the planet is in direct motion. 5. When a planet?s velocity is negative, the planet is in retrograde motion. 6. When a planet?s acceleration is zero, the planet?s velocity is at its maximum or minimum. 7. When a planet?s acceleration is positive, the planet?s velocity is increasing. 8. When a planet?s acceleration is negative, the planet?s velocity is decreasing. Quote Mon Mar 31, 2008 5:31 am