I'm all for the development of technology that could help pave the way to the likes of eventual terraforming other planets, setting up colonies etc.
You'd think Musk would include things like test items to be active electrically and highly susceptible to the Van Allen radiation belts, like some electromagnetic shielding, and if needs be depending on how the rocket flies, dissipate anything like synchrotron radiation produced as a result, or redirect it into a consumable power-source. Harvesting the Van Allen belts like a gigantic betavoltaic nuclear battery, sans radioisotope payload, or something like that would be a clever application of magnetic field based shielding, to create something like say, the biconic cusp configuration used in magnetic plasma confinement, and tapping juice off the 'harvest' so to speak. Even small energy derivation would be neat, reducing power for parts of the craft once 'cruising' up there, assuming it doesn't go boom like a policeman's head in a microwave oven on takeoff. Although with a car? why not use a scientific instrumentation package, would be more bloody useful, and of course, raw materials for the ISS. Since one cannot land a car on mars or the moon and have it work. No atmosphere containing oxygen means no air intake and no air intake means no fuel ignition and thus no driving said terrestrial car Even if it DID land on mars, in one piece (or was meant to).
Radiation shielding from energetic charged particles is going to be critical for any long-haul or/and long-stay colonies on mars, for terraforming assuming we do find it incontrovertibly barren of all life, otherwise, colonists and astronauts, even space tourists are going to get it in the neck.
Personally I like the idea of using something like a biconic cusp, to funnel such energy into collector systems and tap off from the Van Allen belts. Not to mention shielding cargo, electronics etc. from radiation, and putting the space taken by the car to better use with more sensitive test equipment for radiation exposure, for testing shielding systems. And all the better if we could USE the solar winds, and the various radiation for fuel. We can directly turn beta radiation into electricity since it IS energetic electron radiation. Gamma rays not so much, but alpha particles IMO could conceivably be used as a power source too. Hell maybe use the charged particles ( to help power the shields and lower the drain on the fuel supplies carried by the craft, although y-rays are photons way too energetic to convert with a 'solar panel', type arrangement; even if we did have materials which could use gamma radiation, unless to neutralize unwanted ionic species. And then there are heavy molecular ions (HZI) like fully ionized 'stripped' naked iron nuclei etc. cast out from solar nucleosynthesis and the like and as cosmic rays that would of course need to be stopped, and take a lot of energy to do so, if we could manage it, since I'll bet the deceleration of such energetic Fe nuclei would produce significant bremmstrahlung, and resultant X-ray radiation if not moved magnetically, (potentially resulting in synchrotron radiation depending on their either orbiting (emitting cyclotron/synchrotron radiation), or whether just dumped back out of the arse end of the space craft) Absorbing it with a fuckton of lightweight polymer shielding would be impractical for sure (Bremmstrahlung is what is termed 'braking radiation', when high energy particles collide with dense material, are slowed down, and conservation of momentum means that X-rays or potentially at cosmic ray energies, even hard gamma, although I've not done the calculations to determine which. Neither are things astronauts or their equipment want to be bombarded with, so light materials like plastic are used usually to counter the bremmstrahlung production on terrestrial applications. Doing it in space might be another matter entirely)
But we are going to need shielding for longterm astronauts, and for colonists-definitely. Unless we want them to start producing kids with four eyes, eight tails and half a nose, only protruding from their anal sphincter-jaws
Shit, that sounds like the bastard child of a moray eel and jenny mccarthy. Or just scratch the moray eel from the equation and the offspring. She looks close enough already. Hell only knows why ANYBODY would want to shag that vile offspring of satan's own intestinal flora and a lake of fermenting dog shit and piss.