Viewers of Star Trek have heard of an antimatter drive on the Starship Enterprise. Antimatter annihilates normal matter, producing pure energy. One possibility for such a futuristic energy source is to store antimatter charged particles in a vacuum chamber, circulating in a magnetic field, and then extract them as needed. What strength magnetic field is needed to hold antiprotons, moving at 5.0x107m/s in a circular path 2.00 m in radius? Antiprotons have the same mass as protons (1.6726219 x 107 kg) but the opposite (negative) charge.