Scientists found a secret in old Voyager 2 data. This is why we need to revisit Uranus and Neptune

By Ashley Strickland, CNN

Updated 1910 GMT (0310 HKT) March 27, 2020

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NASA's Voyager 2 spacecraft visited Uranus (left) in 1986 and Neptune (right) in 1989.
Photos: Voyager 2 captures planetary portraits
NASA's Voyager 2 spacecraft visited Uranus (left) in 1986 and Neptune (right) in 1989.
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Voyager 2 launched on August 20, 1977. Retrace the steps of its journey across our solar system through some of its most iconic images.
Photos: Voyager 2 captures planetary portraits
Voyager 2 launched on August 20, 1977. Retrace the steps of its journey across our solar system through some of its most iconic images.
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Voyager 2's view of Jupiter during the spacecraft's approach.
Photos: Voyager 2 captures planetary portraits
Voyager 2's view of Jupiter during the spacecraft's approach.
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Voyager 2 provided this image of Jupiter's red spot.<br />
Photos: Voyager 2 captures planetary portraits
Voyager 2 provided this image of Jupiter's red spot.
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The hemisphere of Ganymede that faces away from the Sun displays a great variety of terrain in this mosaic from NASA's Voyager 2.
Photos: Voyager 2 captures planetary portraits
The hemisphere of Ganymede that faces away from the Sun displays a great variety of terrain in this mosaic from NASA's Voyager 2.
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