In addition to viewing the sun's luminous outer atmosphere (corona), which under normal circumstances is lost in the glare of the rays, they will be using the eclipse to calculate the star's current diameter, which changes as the sun expends energy.

CNN: HE GODS WERE DRINKING

During an eclipse scientist are able to measure the effect of the sun on the Earth's atmosphere and observe the violent magnetic storms in outer atmosphere of the sun - the corona.

BBC: 11 August