# What are the perihelion and aphelion distances of the Falcon Heavy second stage?

What are the perihelion and aphelion of the Falcon Heavy second stage containing the Tesla after yesterday's mission?

It seems that Musk's tweet was erroneous, and the orbit's aphelion would be nearer 1.71 AU, instead of 2.61 AU. See Jonathan McDowell's tweet.

This agrees w/ orbit projection now shown in JPL's Horizons: QR= 9.86...E-01 & AD= 1.711...

2458158.500000000 = A.D. 2018-Feb-09 00:00:00.0000 TDB
EC= 2.688810432654559E-01 QR= 9.860573082453878E-01 IN= 1.101912591245855E+00
OM= 3.175070416981074E+02 W = 1.772620363138233E+02 Tp=  2458153.729308890179
N = 6.292640287243981E-01 MA= 3.002024307551933E+00 TA= 5.405918374698258E+00
A = 1.348696130995557E+00 AD= 1.711334953745726E+00 PR= 5.720968998176613E+02

Symbol meaning [1 au= 149597870.700 km, 1 day= 86400.0 s]:

JDTDB    Julian Day Number, Barycentric Dynamical Time
EC     Eccentricity, e
QR     Periapsis distance, q (au)
IN     Inclination w.r.t XY-plane, i (degrees)
OM     Longitude of Ascending Node, OMEGA, (degrees)
W      Argument of Perifocus, w (degrees)
Tp     Time of periapsis (Julian Day Number)
N      Mean motion, n (degrees/day)
MA     Mean anomaly, M (degrees)
TA     True anomaly, nu (degrees)
A      Semi-major axis, a (au)
PR     Sidereal orbit period (day)


The header explains the source of the data is telemetry from the 3rd stage itself, which is derived from it's GPS and other internal data:

Revised: Feb 07, 2018          Tesla Roadster (spacecraft)             -143205

Dummy payload from first launch of SpaceX Falcon Heavy launch vehicle
consisting of a standard Tesla Roadster automobile and a spacesuit-wearing
mannequin nicknamed Starman.

Also includes a Hot Wheels toy model Roadster on the car's dash with a
mini-Starman inside. A data storage device placed inside the car contains
a copy of Isaac Asimov's "Foundation" novels. A plaque on the attachment
fitting between the Falcon Heavy upper stage and the Tesla is etched with
the names of more than 6,000 SpaceX employees.

After orbiting the Earth for 6 hours, a third-stage burn-to-depletion
was completed at approximately 02:30 UTC Feb 7, placing the dummy payload
in a heliocentric orbit having a perihelion of 0.99 au and aphelion
~1.7 au.

This trajectory is a ballistic propagation derived from a post-injection
state provided by SpaceX on 2018-Feb-7, and is based on internal GPS data.

Prediction errors could increase significantly over time due to unmodeled
solar presure, thermal radiation, or outgassing accelerations that are not
characterized.

Launched: 2018-Feb-06 20:45 UTC by Falcon Heavy (FH) from Kennedy Space