The Boomerang Nebula is the coldest location in the known universe: it measures at roughly 2 degrees colder than empty space! This nebula is the result of the death of a red giant star, and the extreme temperature is caused by the rapid expansion of the nebula. According to thermodynamics, if you expand a gas you, cool a gas (just try using one of those compressed air cans for cleaning electronics). However, according to astronomers, a single star's death could not account for a strong enough