6
$\begingroup$

Heat radiators were a big deal for the Space Shuttle - once the bay doors were closed it was important to deorbit quite quickly.

The SpaceX Starship doesn't appear to have specific radiator capabilities. Why is this?

Did the Shuttle just get unusually hot for some reason, or is the Starship structurally able to dissipate heat better - or is it perhaps a yet-to-be-revealed feature?

$\endgroup$
8
  • 4
    $\begingroup$ I can't speak with authority, but one thing worth pointing out is that Starship, as it has been built so far, is not a spacecraft. It is a rocket with some testbed features and mostly empty space where spacecraft systems will eventually go. The radiators on shuttle weren't really to reject solar heating -- insulation did a good enough job on that. They were to reject heat produced by the internal systems -- electronics, machinery, etc, which consumed quite a good bit of power and generated a lot of heat. $\endgroup$ – Tristan Mar 3 at 21:55
  • 2
    $\begingroup$ @Tristan And the 1970s-era electronics involved were substantially more power hungry than today's. Also, that power was supplied by fuel cells which produced quite a bit of their own waste heat. There's also mission length to consider. For short duration flights, even the orbital version might not need radiators, or at least nothing externally identifiable as such, any more than Falcon 9's upper stage does. $\endgroup$ – Christopher James Huff Mar 3 at 22:03
  • 2
    $\begingroup$ Note that Crew Dragon has radiators (part of the junk in the trunk) $\endgroup$ – Organic Marble Mar 3 at 22:04
  • 4
    $\begingroup$ @ChristopherJamesHuff once it's in orbit, something is going to be a radiator, as that's the only way to reject waste heat. It may in fact be a body-conformal radiator, depending on what they do. Both SpaceX Dragon and Boeing Starliner vehicles have conformal body-mounted radiators $\endgroup$ – Tristan Mar 3 at 22:04
  • 1
    $\begingroup$ @Tristan for short duration flights, there's no need to reject waste heat. The vehicle has substantial heat capacity, including header tanks of cryogenic landing propellants that could easily be sized to include excess capacity for cooling purposes, or they could just throw in a ton or two of coolant as an internal heat sink. They'll probably have to have something figured out for dearMoon, but I wouldn't be surprised if they could do all Earth orbit satellite deployment missions without any sort of radiator. $\endgroup$ – Christopher James Huff Mar 3 at 22:20

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.