Uranus yttre ringar avslöjar överraskande skillnader

1 maj 2026

Rapporterad av AI

Astronomer har upptäckt att de yttersta ringarna runt Uranus, kända som mu- och nu-ringarna, skiljer sig markant åt i sammansättning trots att de ser likadana ut. Mu-ringen består av små iskorn, troligen från en liten ismåne, medan nu-ringen är rik på damm och organiska molekyler. Dessa rön, baserade på två decennier av teleskopobservationer, väcker nya frågor om planetens dynamiska ringsystem.

Forskare ledda av Imke de Pater vid University of California, Berkeley, analyserade nästan 20 års data från Keck-teleskopet på Hawaii, rymdteleskopet Hubble och James Webb-teleskopet. Arbetet visade att mu-ringen, den yttersta av Uranus svaga ringar, ser blå ut och består av små iskorn. Däremot ser den intilliggande nu-ringen röd ut och innehåller damm samt komplexa organiska molekyler kallade toliner, enligt studien som publicerats i The Journal of Geophysical Research: Planets (DOI: 10.1029/2025JE009404).

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