With an atmosphere, by mass, of primarily hydrogen (76 per cent) and helium (24 per cent), and by volume of 89 per cent ...

"It's astonishing that even after 4.5 billion years, enough clues remain to let us reconstruct Jupiter's physical state at the dawn of its existence," stated Fred C. Adams, professor of physics and ...

Planets with unusually wide orbits may be normal by-products of the formation of planetary systems. This is suggested by new simulations.