The instability resulting from the relative motion of newly picked-up cometary photoions and the solar wind generates lower hybrid waves that are capable of accelerating electrons to the keV range of energies. These electrons may be responsible for the x-rays from comet C/Hyakutake 1996 B2 seen by the Rontgen X-ray Satellite. The inferred x-ray photon power depends on the electron energy, with keV electrons providing values of photon power two orders of magnitude greater than 100 eV electrons. These observations and in particular, spectral resolution of the x-rays, should provide more insight into the composition of the comet.