Why paint "USA" on spacecraft?

A photo of the Chandra satellite made me wonder: why paint USA (or any other country of origin) on the side of space-bound entities? Is there some risk that future astronauts might mistake it for the OTHER 5 ton satellite in this particular orbit? Or might a foreigner accidentally strap himself into a US space shuttle?

I guess it could be to meet certain registration obligations imposed by the ICAO, but even then, it seems to be of little use to have a label which only bears a nation’s initials.

I guess it could be a national pride reason. Or perhaps to remind USAians what to chant ad nauseum at sporting competitions.

So, why bother?

Extra credit: Calculate the weight of excess unnecessary paint used to paint “USA” and US flags onto spacecraft and convert to spent rocket fuel. Solve for X.

It is for national pride reasons which aren’t that trivial when it comes to immediate recognition by the public as to the magnitude of the project. See one of the heavily customized 747’s that usually serve as Air Force One. They have a prominent “United States of America” logo which could be argued to be a minor security risk if they instead were just plain aluminum colored planes with no logos but that just isn’t done.

There is extra weight for a fancy paint scheme but I don’t know the magnitude. American airlines prefers to keep it fairly plain but there are also aerodynamic issues as well that may favor some paint. The early space shuttle flights had some big paint/weight problems and they just got rid of most of it on the external tank.

National pride, history, and in case it ever goes astray. In years past, exploratory craft carried flags. Too much trouble and too bulky for spacecraft today, so initials and flags are painted on.

National pride. National accomplishment. Does it have to be any more difficult?

So that when we make first contact with extra-terrestrials, they know who’s in charge.

[Zod]
Planet Hoos-tun
[/Zod]

This is something I was thinking of when I made the comment about the weight. The white paint on the external tank weighed about 270kg and they figured “Why are we bothering to paint this white?”.

The STS External Tank was originally painted white to reflect incident radiation in hopes that it would reduce boil-off of the liquid oxygen and liquid hydrogen propellants (which was also done on the Saturn family of rockets). When later analysis showed that this loss was basically insignificant (compared to convective losses from the ambient atmospheric temperature) given the amount of insulation, they stopped painting the ET.

USA, and (typically) the manufacturers’ and integrators’ logos are painted on a rocket booster or space vehicle as an indication of pride. The amount of weight added to paint a logo is basically insignificant for a booster of any significant size (although accounted for in the mass properties summary). Plus, these can be used as a visual indication of roll rate, similar to why the A-4 (V2) and other early rockets were painted in a black-and-white checkerboard pattern.

Stranger

They got rid of the white paint on the external fuel tank fairly quickly because it was much better and useful for more payload to have the paint to be gone. The rest of your questions are simply answered by U.S. pride even at the expense of some efficiency. The Air Force One planes could be much more stealth with a very plain design but they aren’t because of national pride.

So that when Agnes Moorehead gets done whacking the tar out of the spaceship the camera can pull back and let us all in on this week’s Twilight Zone twist ending.