Larissa

astronomy

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June 30, 2026

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Larissa is the fifth moon of Neptune discovered, with a diameter of approximately 216 km (134 miles). It was discovered in 1989 by the Voyager 2 space probe. Larissa orbits Neptune within the planet's ring system, and its irregular shape suggests a heavily cratered surface. Its orbit is nearly circular and lies close to Neptune's equatorial plane. Larissa is named after a figure in Greek mythology associated with the god Poseidon.12

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Neptune
Moons
…of its discoveries, Proteus and Larissa, closely enough to detect both their size and approximate shape. Both bodies are irregular in shape and appear to have heavily cratered surfaces. The sizes of the other four are estimated from a combination of distant images and their brightnesses, based on the assumption…
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…of its discoveries, Proteus and Larissa, closely enough to detect both their size and approximate shape. Both bodies are irregular in shape and appear to have heavily cratered surfaces. The sizes of the other four are estimated from a combination of distant images and their brightnesses, based on the assumption…
Read More