In the zero-gravity airplanes or vomit comet, why does stuff behave like there is no gravity when it is just falling? – Austin B., 11, Scranton, Pennsylvania I have flown many times in zero-gravity ...

So it looks like we'll be talking a lot about gravitational waves over the coming days, but why can't they be called "gravity waves?" In this social media world where brevity is key, it may seem that ...