API VERSION: 1.2 API SOURCE: NASA/JPL Horizons API ******************************************************************************* Revised: Mar 27, 2018 Tesla Roadster (spacecraft) -143205 (solution #10) Tesla Roadster (AKA: Starman, 2018-017A) NOTE: Visibility: 20th magnitude until Feb 20, 22nd magnitude through mid-April Brighter than 26th magnitude into mid-June 2018-Mar-01: Radial non-gravitational acceleration A1 estimated from data (nominally solar radiation pressure) 2018-Mar-27: Two reporting sites (J04 & K93) extend data arc one month. A1 estimate of s10 is reduced 1.2-sigma compared to s9. 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 #10, a fit to 364 ground-based optical astrometric measurements spanning 2018 Feb 8.2 to March 19.1 Trajectory name Start (TDB) Stop (TDB) -------------------------------- ----------------- ----------------- tesla_s10 2018-Feb-07 03:00 2090-Jan-01 00:00 Encounter predictions for s10 (w/radial 1/r^2 non-gravitational acceleration) Date (TDB) Body CA Dist MinDist MaxDist Vrel TCA3Sg Nsigs P_i/p ----------------- ----- ------- ------- ------- ------ ------ ------ ------ 2018 Feb 08.09690 Moon .000936 .000936 .000936 3.961 0.41 47509. 0.000 2020 Oct 07.26768 Mars .049530 .048923 .050242 8.150 27.40 6.63E5 0.000 2035 Apr 22.35934 Mars .015504 .004378 .027978 8.219 170.47 31247. 0.000 2047 Jan 11.89023 Earth .031919 .031716 .032123 4.493 249.70 78398. 0.000 2050 Mar 19.52949 Earth .119113 .113778 .124369 7.397 538.54 2.61E5 0.000 2052 Sep 05.15606 Mars .176363 .172469 .180319 5.738 2185.5 8.68E5 0.000 2067 Apr 15.90202 Mars .043270 .025712 .061471 7.192 1115.0 42565. 0.000 2084 Sep 17.92284 Mars .116962 .093449 .141170 9.753 787.45 6.55E5 0.000 2085 Jan 01.96490 Earth .083063 .049368 .112186 6.224 5208.9 1.00E5 0.000 2088 Mar 09.95754 Earth .049146 .033491 .063322 5.106 4505.2 1.17E5 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 encounter 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, such optional extended output is possible with some extra steps. 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 four lines need be input: the EPOCH, orbital element lines starting with "EC" and "OM", and the non-gravitational acceleration model (line starting with "A1"). SRC lines are needed only for (optional) statistical output and the H & G values only for (optional) visual magnitude output. EPOCH= 2458164.5 EC= .2585469914787243 QR= .9860596231806226 TP= 2458153.620483722645 OM= 317.3549094214575 W = 177.3203028023227 IN= 1.088451292866039 EST=A1 A1= 2.960683526738534E-9 R0= 1. ALN= 1. NM= 2. NK= 0. SRC= -2.057839421666802E-7 7.966781900129693E-9 -1.720426606925749E-9 -4.722542923190676E-7 2.197679131968537E-9 -1.230413802372471E-6 -2.500290306870021E-7 -3.361070889248183E-9 -1.765963020682463E-5 -3.047907547965759E-7 -4.640202045440381E-7 -4.271481116360573E-9 2.657789409005983E-5 1.726818074599357E-6 -1.359673746135991E-6 -2.478836748687631E-5 -2.309863204867099E-8 -.0002351644867403515 -1.875169281895894E-6 -2.063647245529267E-6 -1.670539551586607E-6 -4.019207817588603E-6 -3.128134469402375E-9 -3.034540373576942E-5 1.733661692209129E-7 -7.052327854535979E-7 -2.650181216776434E-7 -1.310976135791957E-10 H= 25.289 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 thermal re-radiation or outgassing accelerations that are not currently characterized but may exist. *******************************************************************************