... Astronomers have realized since the early 1970s that the larger swarms, immense clusters of galaxies millions of light-years across, are immersed within tenuous clouds of hot gas which glow strongly in x-rays. ... The Earth's surface is broken. ... Earth's North Magnetic Pole . ... A magnetic compass does not point toward the true North Pole of the Earth. Rather, it more closely points toward the North Magnetic Pole of the Earth. The North Magnetic Pole is currently located in northern Canada. ...