According to a report in Toronto's National Post newspaper, scientists at the Lawrence Livermore National Laboratory near San Francisco say frozen water will not melt under the right type of hellish conditions.
Writing in the March edition of the American Institute of Physics Journal, the Physical Review Letters, scientists Eric Schwegler and his colleagues say water--and snowballs--would stay frozen at temperatures up to 320 C when subjected to extreme pressure like those at the center of the earth and, presumably, in the underworld.
Water can form hydrogen bonds, which in turn allow oxygen atoms to be arranged in a three-dimensional diamond-like network. Under the extreme pressure of 10 gigapascals (10,000 atmospheres) the scientists say the hudrogen bonds and oxygen network would be substantially altered so that each water molecule is surrounded by 12.9 other molecules, making ice much less likely to melt.
Water molecules common to Earth's surface have 4.5 molecular neighbors.
Although ice melts at 0 C under normal earthly conditions, at a pressure of gigapascals the temperature would have to climb to 320 C to reduce a snowball to a puddle, according to the scientists computer simulations.