There are several cameras in and around the Tesla , but the batteries only lasted 12 hours and there are no sattelite dishes, solar panels or other coms devices mounted to broadcast imagery. It's dead now :/
Well it would have been awesome, but would have also increased the complexity of the system and the number of things that could ho wrong. The main mission was the successful launch of the rocket and the separation and navigation of the booster stages, and they needed as much manpower as possible for that. The roadster was the cherry on top.
How exactly would it have added an appreciable amount complexity to put a small solar powered camera on the car? They already put a space suit in there for shits and giggles
But you must keep the antenna pointed at the Earth. An omnidirectional antenna would not be powerful enough, it would have to be pointed toward and focussed on Earth.
Because solar irradiance per area goes down with the square of the distance from the light source. Since this is going out beyond mars (to around the orbit of Ceres, actually) it gets much less light. Ceres' SMA is around 2.75 AU, which means the panel would get about an eighth of the light it would get at earth. You would need a huge panel to keep it working, since it's both getting less light and only occasionally pointing at the light source.
GoPros use about two watts when recording video. Solar panels produce about 10 watts per square foot at Earth. This means that 1.6 square feet of solar panel is required just to power the go-pro on Earth, with the panel pointed straight at the sun 100% of the time. Scale that out to aphelion, and that means you need 12.8 square feet. Now consider that charging a LiPo battery takes about 20% more power than you end up getting from the battery at discharge, so now we need about 15.3 square feet.
But we're not tracking the sun, so we need to figure out how much more panel we need to make up for the times that we're not pointing at the sun. Even if we assume that we're consistently rotating along an axis that points the panel directly at the sun once per rotation (it won't happen this way, we'll rotate along all three axes instead of just one and that rotation will precess), this means that we'll need at least eight times more panel. Now we need over 120 square feet of panel for a single GoPro. This is larger than the car itself.
And none of this accounts for the massive antenna and its power draw so that we can upload live video to Earth. Even 240p video requires a minimum of 300kbps, which would require a large omnidirectional antenna and constant DSN usage to achieve.
I mean seeing as I've literally written a program for arduino to adjust a small solar panel to find the most intense source of light and I'm at best a mediocre coder I am confident they can figure that out
I'm sure it's on a fixed mount though, not a spacecraft rotating on three axes at multiple RPM. That's not the point though. There are a myriad of other problems involved that make it not worth the effort, such as data uplink rates and solar irradiance from 2.5 AU, or arduino-killing thermals and radiation, or scarce DSN time, or micrometeroid damage to the panel and camera. All these problems have solutions, but they eat up precious and expensive engineering resources just so we can have a live stream that lasts years instead of hours at no financial benefit to SpaceX.
I’d say it’s good that people question things, even if the answers are obvious to enthusiasts or professionals in a particular field. Think of it as a learning experience.
A space suit isn't something that needs to communicate back to earth. I don't think people realize the complexity in that alone. You don't "shits and giggles" a solar powered camera capable of communicating back to earth. That camera needs to be protected, consistently aligned solar panels, and consistently aligned antenna which is a little more complex than slapping a camera on there.
You're really ignoring the primary objective and incredible feat that we just witnessed.
A “small” solar panel would not have nearly enough juice once it gets going away from earth to power a camera, much less the transmitter required to send data back.
I think they wanted to have a pristine looking car up there, and not one with several square meters of solar panels hanging off it. At that point it’s just an inefficient satellite
There aren't really any easy ways to send data from space. It's not like Earth where we have cellular data networks covering entire continents, and thousands of satellites covering the entire planet. The car would need a massive, powerful transmitter (with a power source, maybe rotating solar arrays) with the ability to point at a satellite to send its transmissions to. The fact that the car and the receiving satellite would always be moving, and the fact that the car would rarely have line of sight with the satellite, make it super difficult.
It's not impossible, but it's far from trivial or inexpensive.
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u/[deleted] Feb 07 '18
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