If tachyonic magnetic monopole background neutrinos are the fundamental cause of gravity, gravitational force can be manipulated to travel the empty space without rocket.
If Tachyonic Magnetic Monopole Background Neutrinos were somehow the fundamental carriers or cause of gravity, then manipulating gravity by interacting with this field could, in theory, be possible — but this concept is highly speculative, not supported by current physics, and lacks experimental validation. I think the experimental bounds on neutrino interaction and gravitational strength are extremely strict, making manipulation exceedingly difficult.