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by dylan604 3061 days ago
I saw the video animation of the Tesla separating from the second stage. At that point, the car no longer has thrust, so I'm assuming they've calculated the thrust to be just enough to reach Mars and to be able to fall into orbit. To quote the movie Apollo 13, "we've just put Isaac Newton in the driver's seat". I dearly hope that Musk and team have been referring to the "dummy" in the driver's seat of the Tesla as Isaac.
4 comments

They aren't aiming for Mars orbit. As far as I can tell, they aren't even aiming to come close to Mars. Instead (as far as I can tell) they are aiming to come close to the orbit of Mars, i.e. where Mars will be in 4 or 5 months.
Wait, wait wait. If they aren't putting the Tesla into actual orbit, then what about--50 years from now--when they run into a situation on Mars Base Alpha where the only possible solution to an imminent cascading system failure is to dock with the orbiting Roadster and harvest a crucial part from the drivetrain in order to repair their reactor and save the base?!
> Following launch, Falcon Heavy’s second stage will attempt to place the Roadster into a precessing Earth-Mars elliptical orbit around the sun.
That's not Mars orbit. It's an orbit around the sun with perihelion ~1AU (distance the Earth orbits) and aphelion ~1.5AU (distance Mars orbits [avg]).
So basically they're just throwing a car into space.
Into deep space. This will be SpaceX's first flight beyond Earth orbit.
It will be the first commercial space flight beyond Earth orbit
iirc, they are aiming for Mar's orbit... the general public just thinks that means orbiting Mars.
Yes.
Reading the OPs link it looks like that animation may have had some dramatic license. They are going to do two more mid coarse corrections on the way to “Mars” if I am reading it right. Of course the red planet won’t actually be there on the other side when they get there.

Also note that you can’t “fall into orbit” around Mars, at least not with this sort of trajectory and without an aero rake heat shield. A real mars mission would require a third stage reignition for Mars orbital insertion.

When / if the Tesla nears Mars, it'll be going at escape velocity, and so won't enter orbit. So unless lithobraking is employed, it'll fly straight by, and remain in an orbit around the sun.

Continuing the homage to David Bowie, the dummy driver is called Starman.

From what I understand it won't reach or orbit Mars (not in a current transfer window). It will attempt an approximate Mars-like Hohmann transfer orbit and continue orbiting around the Sun indefinitely.