Neptune is the eighth and farthest-known Solar planet from the Sun. In the Solar System, it is the fourth-largest planet by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times the mass of Earth, slightly more massive than its near-twin Uranus. Neptune is denser and physically smaller than Uranus because its greater mass causes more gravitational compression of its atmosphere. The planet orbits the Sun once every 164.8 years at an average distance of 30.1 AU. It is named after the Roman god of the sea and has the astronomical symbol, representing Neptune's trident. A second symbol, an L-V monogram for 'Le Verrier', analogous to the H monogram for Uranus, was never much used outside of France and is now archaic. Neptune is not visible to the unaided eye and is the only planet in the Solar System found by mathematical prediction rather than by empirical observation.

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News at a glance: Earth science satellites, Global Fund’s haul, and Neptune’s rings

Here is the first direct look at Neptune’s rings in more than 30 years

Infrared view of Neptune shows its rings and moons like never before.

We Have Our First Look at Neptune's Rings in 33 Years, And They're Glorious

Neptune's rings are seen clearly in an image from the James Webb t

Sparkly Image of Neptune's Rings Comes into View from JWST

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Ghostly rings of Neptune shine in new James Webb Telescope images

Incredible New Webb Telescope Image of Neptune Captures Never Seen Ring Details

New Webb image captures clearest view of Neptune's rings in decades

Neptune and Its Rings Glow in Webb Telescope’s Portrait

James Webb Space Telescope captures stunning image of Neptune's rings and moons

JWST has captured an astonishing view of Neptune and its rings

James Webb Space Telescope captures stunning image of Neptune's rings and moons

Webb Focuses on Neptune, Its Moons and Ring System

New Webb Image Captures Clearest View of Neptune's Rings in Decades

New Webb Image Captures Clearest View of Neptune’s Rings in Decades

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ALMA Finds Evidence of Neptune-Mass Protoplanet around LkCa 15

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