If a proton is to orbit Earth at the equator by using Earth's magnetic field to supply part of the necessary centripetal force, then in what direction should the proton move to accomplish this? If a proton is to orbit Earth at the equator by using Earth's magnetic field to supply part of the necessary centripetal force, then in what direction should the proton move to accomplish this? Toward the moon Northward Southward Eastward Westward