The moon is not a planet.
Figuring out something that works well in Mars' thin (but still there) atmosphere, especially a helicopter, is really impressive. The celestial body classification is just a cherry on top.
Edit: Phantom 4 is 1.3 kg and blades are 45g
Also, Isaac Asimov considered the system a dual-planet system as the Moon's path around the sun is at no point convex nor retrograde.
1% is an arbitrary threshold and solar orbit is dependent on external circumstances rather than the Earth-Moon system itself.
> Earth-Moon centre of mass is inside Earth, so, it's
> obvious that the Moon is orbiting the Earth, not both
> orbiting something else.
I'd tend to say that separating them further would tend more towards planet-moon. Yet doing so moves the system's center of mass outside the larger body, so would actually push the system into the dual-planet definition by that criterion.
The barycentre of the Sun and Jupiter isn't inside of the Sun.. so does that mean Jupiter doesn't orbit the Sun?