Jupiter’s Great Red Spot may have disappeared and reformed

Jupiter’s Great Red Spot may be younger than many astronomers thought. It is commonly accepted that the enormous storm was first observed by Giovanni Cassini in 1665, but it turns out that the spot Cassini saw was probably a different one to the vortex visible now.

The Great Red Spot, a storm larger than the planet Earth, has been continuously observable since 1831. But an enormous storm was also visible at the same location on Jupiter from 1665 to 1713, and astronomers have…