With President Trump pledging to send astronauts to Mars, cutting-edge advertisers may be wondering whether we can plant more than just the “stars and stripes” there.  

So, can you place a giant, lit up billboard on Mars that shines down on Earth?  Probably not – at least if you can see the advertising with the naked eye.  

Federal law essentially prohibits obstrusive space advertising, which is defined as “advertising in outer space that is capable of being recognized by a human being on the surface of the Earth without the aid of a telescope or other technological device.”  (Likely due to the limitations on U.S. jurisdiction, the law actually prohibits the launching of rockets containing obstrusive space advertising.)  Even if you can't place that giant billboard on Mars, the law doesn't prohibit you, however, from advertising on the side of the rocket that may take the astronauts there.  

Interestingly, late last year, the American Astronomical Society passed a resolution calling for an international treaty banning obstrusive space advertising, in order to protect “clear and unobstructed views of the cosmos.”  Apparently, the resolution was in response to what was some genuine interest by some companies around the world in developing technology to advertise in space.