Nov
01

From Earth to the Solar System: Neptune

THE DISAPPEARING DARK SPOT: Dark, cold, and whipped by supersonic winds, Neptune is the furthest away from the Sun of the hydrogen and helium gas giants in our Solar System. No probe has ever been sent there, and its thick atmosphere acts as a dark veil to the surface below. We do know that it has 13 moons and a ring system, and takes almost 165 Earth years to orbit the Sun. Neptune’s atmosphere extends to great depths, gradually merging into water and other melted ices over a heavier, approximately Earth-sized, solid core. In 1989, NASA’s Voyager 2 spacecraft tracked a large, oval-shaped storm called the called the ‘Great Dark Spot’ (similar to the Great Red Spot on Jupiter). In 1994 when NASA’s Hubble Space Telescope imaged the planet, no sign of the Great Dark Spot could be seen. Image Credit: NASA/JPL


Posted: 1 November 2011
About the Author:

Alex di Giovanni is primarily responsible for "other duties as assigned" in the Office of Communications and External Affairs. She has been with the Smithsonian since 2006 and plans to be interred in the Smithson crypt.