>>16719080 (OP)Depends on what it looks like and what other observables there were. If it softly lands like a UFO in a movie without blowing stuff around we can conclude something like antigravity exists. If it flies all the way to space and doesn't generate any radiation or chemical waste we could infer there must be some new way to generate power. There might be other observables we could take advantage of too, like gravitational waves, neutrino emissions(if it uses fission or fusion we'll know), radar, optical, thermal It's on the white house lawn, just the sensors that are already there would be pretty informative. And there are a bunch of ways we could probe it non destructively
>>16719089Then we can combine those observations. It's 20-fucking-25 we can see with more than just our eyes. Whatever effect it has on ambient cellphone networks would be informative