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Plugging Starman / Tesla Roadster into Starry Night astronomy program
Cool, this guy's youtube video https://www.youtube.com/watch?v=OQgDUrNOkVs
gave me the info I've been looking for...
that Tesla Roadster/Starman's designation in the JPL database is
-143205
So I emailed the JPL email-bot and it spat back this:
Revised: Feb 20, 2018 Tesla Roadster (spacecraft) -143205
(solution #8)
Tesla Roadster (AKA: Starman, 2018-017A)
NOTE:
The trajectory estimate will be updated here in the days ahead if more
measurement data is reported.
Visibility: 20th magnitude until Feb 20, 22nd magnitude through early April,
brighter than 26th magnitude into June.
LAUNCHED:
2018-Feb-06 20:45 UTC by Falcon Heavy (FH-1) from Kennedy Space Center, USA
(launchpad 39A)
BACKGROUND:
Dummy payload from the first launch of SpaceX Falcon Heavy launch vehicle.
Consists 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 5 hours, a third burn by the second stage 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 ~1.67 au.
The object stack consists of a Merlin 1D Vacuum second stage with Extended
Nozzle, Payload Attachment Fitting, and Tesla Roadster on mount.
Roadster mass: ~1250 kg (with batteries), ~800 kg (without ESS/batteries)
TRAJECTORY:
This trajectory is based on JPL solution #8, a fit to 330 ground-based
optical astrometric measurements spanning 2018 Feb 8.2 to 18.3
Trajectory name Start (TDB) Stop (TDB)
-------------------------------- ----------------- -----------------
tesla_s8 2018-Feb-07 03:00 2048-Jan-01 00:00
Encounter predictions for s8 (with gravity-only dynamics):
Date (TDB) Body CA Dist MinDist MaxDist Vrel TCA3Sg Nsigs P_i/p
----------------- ----- ------- ------- ------- ------ ------ ------ ------
2018 Feb 08.09700 Moon .000936 .000936 .000936 3.962 0.42 40889. 0.000
2020 Oct 07.27671 Mars .049248 .048632 .049996 8.132 29.03 6.68E5 0.000
2035 Apr 22.31261 Mars .021004 .007334 .035038 8.315 142.40 37596. 0.000
2047 Jan 12.52967 Earth .029674 .019448 .039078 4.422 4391.7 73261. 0.000
2050 Mar 19.02367 Earth .113309 .089472 .135482 7.215 2540.6 2.42E5 0.000
Date = Nominal encounter time (Barycentric Dynamical Time)
CA_Dist = Highest probability close approach distance to body, au
MinDist = 3-sigma minimum encounter distance, au
MaxDist = 3-sigma maximum encounter distance, au
Vrel = Relative velocity at nominal encounter time, km/s
TCA3Sg = 3-sigma uncertainty in close enocunter time, minutes
Nsigs = Number of sigmas to encounter body at nominal encounter time
P_i/p = Linearized probability of impact
NOTE:
How to obtain optional statistical uncertainty output & generate an SPK file:
Since this is a spacecraft and not part of the asteroid and comet database
which normally holds orbit covariance data, some functions like statistical
output and SPK file generation aren't automatically available for this object.
However, with some extra steps, such optional extended output is possible
in this case.
To propagate statistical uncertainties for this object, the full statistical
orbit solution (given below) can be manually input back into Horizons as a
"user-defined object" using the telnet or e-mail interfaces (not possible
with the browser interface).
To do this and activate statistical or SPK file output ...
Using the telnet interface (command-line "telnet ssd.jpl.nasa.gov 6775"),
enter ";" to drop into user-input mode then cut-and-paste each line shown
below, one at a time. The lines of numbers after SRC must be in the order
shown.
For SPK file generation, only the first three lines need be input; the
EPOCH and orbital element lines starting with "EC" and "OM".
SRC lines are needed only for statistical output, the H & G values only
for visual magnitude output.
EPOCH= 2458161.5
EC= .2605617969679692 QR= .986061946474019 TP= 2458153.658830588476
OM= 317.4100916677914 W = 177.3002372702468 IN= 1.096465162480806
SRC= 2.215648860985859E-7 -6.978166940838508E-9 1.747703101626183E-9
6.838107985591074E-7 -2.785083038219253E-9 1.623752951763019E-6
2.676579519565857E-7 4.428313428313642E-9 2.245727600074333E-5
3.906772819853299E-7 7.548892835768459E-7 6.893942303902765E-9
-2.440888593071481E-5 -2.00112779439303E-6 1.694365063698046E-6
2.774779936165686E-5 2.475181137432366E-8 .0002597834543639343
2.183107215200873E-6 2.157965362478634E-6 1.889595619028567E-6
H= 25.257 G= 0.15
When done, press a blank return to exit input mode.
Enter "J" at the prompt to indicate heliocentric J2000 ecliptic data has
been supplied. Then at the next prompt, input an arbitrary name
(i.e., Roadster).
Horizons will then proceed as usual, but with statistical output and SPK
file generation now available as options.
A basic and identical tracking ephemeris can be produced without doing any
of this, but statistical uncertainty quantities requested will be marked
"n.a.", meaning not available, and SPK generation won't be an option..
NOTE: long-term predictions
Over time, trajectory prediction errors could increase more rapidly
than the formal statistics indicate due to unmodeled solar pressure,
thermal re-radiation, or outgassing accelerations that are not currently
characterized but may exist.
*******************************************************************************
*******************************************************************************
Ephemeris / MAIL_REQUEST Thu Mar 1 10:27:41 2018 Pasadena, USA / Horizons
*******************************************************************************
Target body name: SpaceX Roadster (spacecraft) (-143205) {source: tesla_s8}
Center body name: Sun (10) {source: DE431mx}
Center-site name: BODY CENTER
*******************************************************************************
Start time : A.D. 2018-Mar-02 13:25:00.0000 TDB
Stop time : A.D. 2018-Mar-02 13:25:01.0000 TDB
Step-size : 60 minutes
*******************************************************************************
Center geodetic : 0.00000000,0.00000000,0.0000000 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 0.00000000,0.00000000,0.0000000 {E-lon(deg),Dxy(km),Dz(km)}
Center radii : 696000.0 x 696000.0 x 696000.0 k{Equator, meridian, pole}
Keplerian GM : 1.3271244004193930E+11 km^3/s^2
Output units : KM-S, deg, Julian Day Number (Tp)
Output type : GEOMETRIC osculating elements
Output format : 10
Reference frame : ICRF/J2000.0
Coordinate systm: Ecliptic and Mean Equinox of Reference Epoch
*******************************************************************************
JDTDB
EC QR IN
OM W Tp
N MA TA
A AD PR
*******************************************************************************
$$SOE
2458180.059027778 = A.D. 2018-Mar-02 13:25:00.0000 TDB
EC= 2.563932000786699E-01 QR= 1.475121159297403E+08 IN= 1.080002051466089E+00
OM= 3.172299386700017E+02 W = 1.773818012354794E+02 Tp= 2458153.549923829734
N = 7.470539034750749E-06 MA= 1.711042235902635E+01 TA= 2.937830245190548E+01
A = 1.983738125382210E+08 AD= 2.492355091467017E+08 PR= 4.818929374779865E+07
$$EOE
*******************************************************************************
Coordinate system description:
Ecliptic and Mean Equinox of Reference Epoch
Reference epoch: J2000.0
XY-plane: plane of the Earth's orbit at the reference epoch
Note: obliquity of 84381.448 arcseconds wrt ICRF equator (IAU76)
X-axis : out along ascending node of instantaneous plane of the Earth's
orbit and the Earth's mean equator at the reference epoch
Z-axis : perpendicular to the xy-plane in the directional (+ or -) sense
of Earth's north pole at the reference epoch.
Symbol meaning:
JDTDB Julian Day Number, Barycentric Dynamical Time
EC Eccentricity, e
QR Periapsis distance, q (km)
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/sec)
MA Mean anomaly, M (degrees)
TA True anomaly, nu (degrees)
A Semi-major axis, a (km)
AD Apoapsis distance (km)
PR Sidereal orbit period (sec)
Geometric states/elements have no aberrations applied.
Computations by ...
Solar System Dynamics Group, Horizons On-Line Ephemeris System
4800 Oak Grove Drive, Jet Propulsion Laboratory
Pasadena, CA 91109 USA
Information: http://ssd.jpl.nasa.gov/
Connect : telnet://ssd.jpl.nasa.gov:6775 (via browser)
http://ssd.jpl.nasa.gov/?horizons
telnet ssd.jpl.nasa.gov 6775 (via command-line)
Author : Jon.D.Giorgini@jpl.nasa.gov
*******************************************************************************
So....
So, plugging these into my very ancient Starry Night (1.0 probably) I have 7,
but I'm more comfortable using the old one.
New orbiting object, asteroid
Near-circular Eliptic 2000
1 mean distance (a) in AU
2 eccentricity (e)
3 inclination (i)
4 ascending node
5 arg of pericenter
6 Mean Anomaly L
7 epoch (julian day)
1 A = 1.983738125382210E+08 in kilometers, convert to AU:
2 eccentricity EC= 2.563932000786699E-01
3 IN= 1.080002051466089E+00
4 OM= 3.172299386700017E+02
5 W = 1.773818012354794E+02
6 MA= 1.711042235902635E+01
7 EPOCH= 2458161.5
-------
so, 1: 198373812.5382210 kilometers / # of kilometers in an AU 1.496e+8
198373812.5382210 / 149600000 = AU 1.326028158677948
2. eccentricity .2563932
3 inclination 1.080002051466089
4 ascending node 317.2299386700017
5 arg of pericenter 177.3818012354794
6. MA 17.11942235902635
7 EPOCH= 2458161.5
Now I make it 1 kilometer across (sue me, I exagerate) asteroid
and paint it with a JPG of starman
Looks right to me. I'm at least in the ballpark.
I guarantee I'm not off by more than the width of 1 solar system! :)
gave me the info I've been looking for...
that Tesla Roadster/Starman's designation in the JPL database is
-143205
So I emailed the JPL email-bot and it spat back this:
Revised: Feb 20, 2018 Tesla Roadster (spacecraft) -143205
(solution #8)
Tesla Roadster (AKA: Starman, 2018-017A)
NOTE:
The trajectory estimate will be updated here in the days ahead if more
measurement data is reported.
Visibility: 20th magnitude until Feb 20, 22nd magnitude through early April,
brighter than 26th magnitude into June.
LAUNCHED:
2018-Feb-06 20:45 UTC by Falcon Heavy (FH-1) from Kennedy Space Center, USA
(launchpad 39A)
BACKGROUND:
Dummy payload from the first launch of SpaceX Falcon Heavy launch vehicle.
Consists 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 5 hours, a third burn by the second stage 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 ~1.67 au.
The object stack consists of a Merlin 1D Vacuum second stage with Extended
Nozzle, Payload Attachment Fitting, and Tesla Roadster on mount.
Roadster mass: ~1250 kg (with batteries), ~800 kg (without ESS/batteries)
TRAJECTORY:
This trajectory is based on JPL solution #8, a fit to 330 ground-based
optical astrometric measurements spanning 2018 Feb 8.2 to 18.3
Trajectory name Start (TDB) Stop (TDB)
-------------------------------- ----------------- -----------------
tesla_s8 2018-Feb-07 03:00 2048-Jan-01 00:00
Encounter predictions for s8 (with gravity-only dynamics):
Date (TDB) Body CA Dist MinDist MaxDist Vrel TCA3Sg Nsigs P_i/p
----------------- ----- ------- ------- ------- ------ ------ ------ ------
2018 Feb 08.09700 Moon .000936 .000936 .000936 3.962 0.42 40889. 0.000
2020 Oct 07.27671 Mars .049248 .048632 .049996 8.132 29.03 6.68E5 0.000
2035 Apr 22.31261 Mars .021004 .007334 .035038 8.315 142.40 37596. 0.000
2047 Jan 12.52967 Earth .029674 .019448 .039078 4.422 4391.7 73261. 0.000
2050 Mar 19.02367 Earth .113309 .089472 .135482 7.215 2540.6 2.42E5 0.000
Date = Nominal encounter time (Barycentric Dynamical Time)
CA_Dist = Highest probability close approach distance to body, au
MinDist = 3-sigma minimum encounter distance, au
MaxDist = 3-sigma maximum encounter distance, au
Vrel = Relative velocity at nominal encounter time, km/s
TCA3Sg = 3-sigma uncertainty in close enocunter time, minutes
Nsigs = Number of sigmas to encounter body at nominal encounter time
P_i/p = Linearized probability of impact
NOTE:
How to obtain optional statistical uncertainty output & generate an SPK file:
Since this is a spacecraft and not part of the asteroid and comet database
which normally holds orbit covariance data, some functions like statistical
output and SPK file generation aren't automatically available for this object.
However, with some extra steps, such optional extended output is possible
in this case.
To propagate statistical uncertainties for this object, the full statistical
orbit solution (given below) can be manually input back into Horizons as a
"user-defined object" using the telnet or e-mail interfaces (not possible
with the browser interface).
To do this and activate statistical or SPK file output ...
Using the telnet interface (command-line "telnet ssd.jpl.nasa.gov 6775"),
enter ";" to drop into user-input mode then cut-and-paste each line shown
below, one at a time. The lines of numbers after SRC must be in the order
shown.
For SPK file generation, only the first three lines need be input; the
EPOCH and orbital element lines starting with "EC" and "OM".
SRC lines are needed only for statistical output, the H & G values only
for visual magnitude output.
EPOCH= 2458161.5
EC= .2605617969679692 QR= .986061946474019 TP= 2458153.658830588476
OM= 317.4100916677914 W = 177.3002372702468 IN= 1.096465162480806
SRC= 2.215648860985859E-7 -6.978166940838508E-9 1.747703101626183E-9
6.838107985591074E-7 -2.785083038219253E-9 1.623752951763019E-6
2.676579519565857E-7 4.428313428313642E-9 2.245727600074333E-5
3.906772819853299E-7 7.548892835768459E-7 6.893942303902765E-9
-2.440888593071481E-5 -2.00112779439303E-6 1.694365063698046E-6
2.774779936165686E-5 2.475181137432366E-8 .0002597834543639343
2.183107215200873E-6 2.157965362478634E-6 1.889595619028567E-6
H= 25.257 G= 0.15
When done, press a blank return to exit input mode.
Enter "J" at the prompt to indicate heliocentric J2000 ecliptic data has
been supplied. Then at the next prompt, input an arbitrary name
(i.e., Roadster).
Horizons will then proceed as usual, but with statistical output and SPK
file generation now available as options.
A basic and identical tracking ephemeris can be produced without doing any
of this, but statistical uncertainty quantities requested will be marked
"n.a.", meaning not available, and SPK generation won't be an option..
NOTE: long-term predictions
Over time, trajectory prediction errors could increase more rapidly
than the formal statistics indicate due to unmodeled solar pressure,
thermal re-radiation, or outgassing accelerations that are not currently
characterized but may exist.
*******************************************************************************
*******************************************************************************
Ephemeris / MAIL_REQUEST Thu Mar 1 10:27:41 2018 Pasadena, USA / Horizons
*******************************************************************************
Target body name: SpaceX Roadster (spacecraft) (-143205) {source: tesla_s8}
Center body name: Sun (10) {source: DE431mx}
Center-site name: BODY CENTER
*******************************************************************************
Start time : A.D. 2018-Mar-02 13:25:00.0000 TDB
Stop time : A.D. 2018-Mar-02 13:25:01.0000 TDB
Step-size : 60 minutes
*******************************************************************************
Center geodetic : 0.00000000,0.00000000,0.0000000 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 0.00000000,0.00000000,0.0000000 {E-lon(deg),Dxy(km),Dz(km)}
Center radii : 696000.0 x 696000.0 x 696000.0 k{Equator, meridian, pole}
Keplerian GM : 1.3271244004193930E+11 km^3/s^2
Output units : KM-S, deg, Julian Day Number (Tp)
Output type : GEOMETRIC osculating elements
Output format : 10
Reference frame : ICRF/J2000.0
Coordinate systm: Ecliptic and Mean Equinox of Reference Epoch
*******************************************************************************
JDTDB
EC QR IN
OM W Tp
N MA TA
A AD PR
*******************************************************************************
$$SOE
2458180.059027778 = A.D. 2018-Mar-02 13:25:00.0000 TDB
EC= 2.563932000786699E-01 QR= 1.475121159297403E+08 IN= 1.080002051466089E+00
OM= 3.172299386700017E+02 W = 1.773818012354794E+02 Tp= 2458153.549923829734
N = 7.470539034750749E-06 MA= 1.711042235902635E+01 TA= 2.937830245190548E+01
A = 1.983738125382210E+08 AD= 2.492355091467017E+08 PR= 4.818929374779865E+07
$$EOE
*******************************************************************************
Coordinate system description:
Ecliptic and Mean Equinox of Reference Epoch
Reference epoch: J2000.0
XY-plane: plane of the Earth's orbit at the reference epoch
Note: obliquity of 84381.448 arcseconds wrt ICRF equator (IAU76)
X-axis : out along ascending node of instantaneous plane of the Earth's
orbit and the Earth's mean equator at the reference epoch
Z-axis : perpendicular to the xy-plane in the directional (+ or -) sense
of Earth's north pole at the reference epoch.
Symbol meaning:
JDTDB Julian Day Number, Barycentric Dynamical Time
EC Eccentricity, e
QR Periapsis distance, q (km)
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/sec)
MA Mean anomaly, M (degrees)
TA True anomaly, nu (degrees)
A Semi-major axis, a (km)
AD Apoapsis distance (km)
PR Sidereal orbit period (sec)
Geometric states/elements have no aberrations applied.
Computations by ...
Solar System Dynamics Group, Horizons On-Line Ephemeris System
4800 Oak Grove Drive, Jet Propulsion Laboratory
Pasadena, CA 91109 USA
Information: http://ssd.jpl.nasa.gov/
Connect : telnet://ssd.jpl.nasa.gov:6775 (via browser)
http://ssd.jpl.nasa.gov/?horizons
telnet ssd.jpl.nasa.gov 6775 (via command-line)
Author : Jon.D.Giorgini@jpl.nasa.gov
*******************************************************************************
So....
So, plugging these into my very ancient Starry Night (1.0 probably) I have 7,
but I'm more comfortable using the old one.
New orbiting object, asteroid
Near-circular Eliptic 2000
1 mean distance (a) in AU
2 eccentricity (e)
3 inclination (i)
4 ascending node
5 arg of pericenter
6 Mean Anomaly L
7 epoch (julian day)
1 A = 1.983738125382210E+08 in kilometers, convert to AU:
2 eccentricity EC= 2.563932000786699E-01
3 IN= 1.080002051466089E+00
4 OM= 3.172299386700017E+02
5 W = 1.773818012354794E+02
6 MA= 1.711042235902635E+01
7 EPOCH= 2458161.5
-------
so, 1: 198373812.5382210 kilometers / # of kilometers in an AU 1.496e+8
198373812.5382210 / 149600000 = AU 1.326028158677948
2. eccentricity .2563932
3 inclination 1.080002051466089
4 ascending node 317.2299386700017
5 arg of pericenter 177.3818012354794
6. MA 17.11942235902635
7 EPOCH= 2458161.5
Now I make it 1 kilometer across (sue me, I exagerate) asteroid
and paint it with a JPG of starman
Looks right to me. I'm at least in the ballpark.
I guarantee I'm not off by more than the width of 1 solar system! :)