25 ........4285.075 + 1.26
Uranus-Pluto. Synodic period - 127.2794y.
...First order........ 2 ........ 254.2794 + 13.13298 + 9.57037
...Second order...... 27 ....... 3432.774 - 2.7047
37 ....... 4704.1689 - 2.948
Neptune-Pluto. Synodic period -(2 x 247y) 492.3280y.
...First order........ 1 ........ 492.3280 + 2.4444 - 4.4555
...Second order..... 147 ......72,372.25 + 0.3
81 ......39,878.6 + 0.46
(a) After 12 conjunctions, there is a separation of 180.25°.
In the last 2,500 years the Uranus-Neptune first order synodic period has
averaged approx. 171.Oy; that of Neptune-Pluto, 493.5y, and it will become
slightly longer.
The two hypothetical outermost planets indicated by the application of the Richardson formula, which are identified as
X and Y, appear to answer to the following calculations:
.....................................Revolutionary Period, in Years
....Planet....Distance from the Sun......Tropical......Sidereal
....Pluto............39.4574 AU...........245.33.........247.7
....Planet X.........74.2 AU..............625............640.
....Planet Y.......1374 AU...............1515..........11608.
Their first order recurrence cycle has been approximated, as follows:
....Cycle...Number of Conjunctions...Tropical Years...Synodic Cycle
...Pluto-X.................3..............1230............410y
...X-Y.....................3..............3183...........1061.3y