All four of the sun’s giant planets emit more energy than they receive from the sun. Like the sun’s other giant worlds, Uranus (seen in this 1986 photo from the Voyager 2 spacecraft) radiates more energy than the sun gives it, though not nearly as strongly as its massive peers do. JPL/NASA ===================================================================== Uranus emits more energy than it gets from the sun, two new studies report — a discovery that contradicts findings from the venerable Voyager spacecraft. When Voyager 2 sped past Uranus on January 24, 1986, the spacecraft detected no significant excess heat from the planet, making it...