Pos/Vel from Universal Elements
CALL sla_UE2PV (DATE, U, PV, JSTAT)
DATE | D | date (TT Modified Julian Date = JD−2400000.5) |
U | D(13) | universal orbital elements (updated; Note 1) |
| ||
(1) |
| combined mass (M+m) |
(2) |
| total energy of the orbit (α) |
(3) |
| reference (osculating) epoch (t0) |
(4-6) |
| position at reference epoch (r0) |
(7-9) |
| velocity at reference epoch (v0) |
(10) |
| heliocentric distance at reference epoch |
(11) |
| r0.v0 |
(12) |
| date (t) |
(13) |
| universal eccentric anomaly (ψ) of date, approx |
PV | D(6) | heliocentric [x,y,z,ẋ,ẏ,ż], equatorial, J2000 |
| ||
|
| (AU, AU/s; Note 1) |
| ||
JSTAT | I | status: |
| ||
|
| 0 = OK |
|
||
|
| −1 = radius vector zero |
|
||
|
| −2 = failed to converge |
It is not obligatory to use sla_EL2UE to obtain the parameters. However, it should be noted that because sla_EL2UE performs its own validation, no checks on the contents of the array U are made by the present routine.