Hey lads, This might be a stupid question, but I've been thinking about it. Let's say, we make a visit to CERN particle accelerator... They accelerate a particle (or a football) to about 298 thousand km/s. (c = 300 thousand rounded). And then I accelerate a particle, or something else, to about 3000 km/s. And at the exact same moment, they move in opposite direction, so their relative speed is faster than 300 thousand km/s. Is this possible? Sorry if it's a stupid question... Francis.