Enormous deposits of helium--estimated at 54 billion cubic feet--have been discovered in Tanzania's Rift Valley and could relieve dwindling supplies of the rare gas, which is used in hospitals in MRI scanners as well as in spacecraft, telescopes and radiation monitors. "This is seven times the current global consumption," said Professor Chris Ballentine of Oxford University, one of the researchers working on the project. "This is enough to fill over 1.2 million medical MRI scanners." Here are 10 facts you probably didn't know about Helium - the second element in the periodic table. More about GE in Africa in this BRIEFING.