Astronomy Picture of the Day . ... The Hydra Cluster of Galaxies . ... White Oval Clouds on Jupiter . ... What are those white ovals all over Jupiter? ... The above pictured white ovals are located near the Great Red Spot, and have persisted on Jupiter since the 1930s. The Great Red Spot has persisted for at least 300 years. Jupiter's Ring Halo . ... Why do many galaxies appear as spirals? ... The above pictures taken by Mars Pathfinder highlight how clouds vary during the end of a Martian day. ...