Ross Cunniff

In my previous post, I simulated my best available information on the SpaceX Tesla roadster. In this post, I investigate a range of possible futures for the Tesla. I started with JPL's HORIZONS ephemeris . It turns out that it can evaluate probabilistic orbits; here are its predictions for close planetary encounters by the Tesla given the current uncertainties in its position:           Date (TDB)      Body   CA Dist  MinDist  MaxDist   Vrel  TCA3Sg  Nsigs  P_i/p   ----------------------  -----  -------  -------  -------  ------ ------ ------ -------   A.D. 2020 Oct 07.26668  Mars   .049589  .047961  .052381   8.153  92.21 1.57E5 .000000   A.D. 2035 Apr 22.36925  Mars   .014376  .003802  .055862   8.199 601.42 10658. .000000   A.D. 2047 Jan 11.95105  Earth  .031798...

Executive summary: its orbit is not very stable. Photo courtesy of SpaceX On February 6, 2018, SpaceX performed its test launch of its new Falcon Heavy rocket. It was a very successful launch. As most people know, the payload was Elon Musk's 2008 Tesla Roadster . After orbiting the Earth for a few hours, the upper stage lit up again and sent the Tesla on a Solar orbit: Musk has famously tweeted that the Tesla will be orbiting for "a billion years." This is extremely unlikely. In fact, it will likely crash into the Sun, or a planet (most likely Earth but perhaps Venus), or be ejected from the Solar System. To try to characterize this, I went to NASA's JPL Horizons web page to get current Cartesian elements for the Tesla (these are vectors of position and velocity). These are the elements as of today, February 10, 2018: 2458159.500000000 = A.D. 2018-Feb-10 00:00:00.0000 TDB  X =-7.690802173107607E-01 Y = 6.236475652855626E-01 Z =-1.393643118679943E-03 ...