Liquid Metal (Sirius XM) Guy were severed from the channel as part of XM Liquid Metal's signoff. The Hard Attack play list has also been changed, featuring acts that were once heard on the former XM channel Squizz. Mercury has been replaced by Beyond the Pit, which airs in the middle of the night, instead of its former evening drive time slot. As part of the Sirius XM update, Sirius 27 Hard Attack was renamed Liquid Metal (taking the name of the channel that was on XM channel 42). Original subscribers to Sirius and XM have been disappointed because the title change, and others
Liquid hydrogen The first synthesis of the stable isomer form of liquid hydrogen, parahydrogen, was achieved by Paul Harteck and Karl Friedrich Bonhoeffer in 1929. The two nuclei in a dihydrogen molecule can have two different spin states. Parahydrogen, in which the two nuclear spins are antiparallel, is more stable than orthohydrogen, in which the two are parallel. At room temperature, gaseous hydrogen is mostly in the ortho isomeric form due to thermal energy, but an ortho-enriched mixture is only metastable when liquified at low temperature. It slowly undergoes an exothermic reaction to become the para isomer, with enough energy released as