Hydrogen in strong magnetic fields in neutron star surfaces

In magnetic fields of very much more than 2 x 10(9) G, polyatomic hydrogen molecules, in the form of long chains, are stable. in neutron star surfaces, fields of 10(13) G are commonplace and 10(15) G has been reported. Liquid hydrogen can form at the higher field with a zero-pressure density of about 10(6) g cm(-3). At these densities, hydrogen can burn to helium by pycnonuclear reactions even at low temperatures-the 'real cold fusion'.