The U.S. space agency NASA will launch a pair of space probes Wednesday night on a unique mission to study the sun.
NASA says the $550 million Solar Terrestrial Relations Observatory mission will use the moon's gravity to send the two probes into different orbits around the sun. The probes will take three-dimensional views of the sun to observe its intense and dangerous gas eruptions, known as coronal mass ejections.
CMEs can blow up to 10 billion tons of the sun's atmosphere into space. The eruptions can damage electrical power grids when they hit the Earth's atmosphere, and threaten astronauts conducting spacewalks outside the protection of their spacecraft.