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Jupiter's moon Europa probably has a salty ocean beneath its ice, which may hold about twice as much water as all of Earth's oceans combined.

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Europa is a little smaller than our Moon. NASA scientists estimate that its ice shell is 15 to 25 kilometres thick and the ocean beneath it 60 to 150 kilometres deep. The heat that keeps the water liquid comes not from the Sun but from tides: as Europa circles Jupiter, the giant planet's gravity squeezes and stretches it, warming its interior. The strongest evidence came from NASA's Galileo spacecraft around 2000, which found that Europa disturbs Jupiter's magnetic field in the way a buried layer of salty water would. Because the ocean probably touches a rocky seafloor, it could hold the chemistry that life needs. NASA's Europa Clipper, launched in October 2024, is due to reach Jupiter in 2030.

Türkçe oku
Jüpiter'in uydusu Europa'nın buz kabuğunun altında tuzlu bir okyanus olduğu düşünülüyor. Bu okyanusta, Dünya'daki bütün okyanusların toplamının iki katı kadar su bulunabilir.

Europa, Ay'dan biraz küçüktür. NASA'nın bilim insanlarına göre buz kabuğu 15 ile 25 kilometre kalınlığında, altındaki okyanus ise 60 ile 150 kilometre derinliğindedir. Suyu sıvı tutan ısı Güneş'ten değil, gelgitten gelir: Europa, Jüpiter'in çevresinde dönerken dev gezegenin çekimi onu sıkıştırıp esnetir ve iç kısmını ısıtır. En güçlü kanıtı, 2000 dolaylarında NASA'nın Galileo aracı buldu: Europa, Jüpiter'in manyetik alanını tam da yer altındaki tuzlu bir su katmanının bozacağı biçimde bozuyordu. Okyanus büyük olasılıkla kayalık bir deniz tabanına değdiği için yaşamın gerektirdiği kimyaya sahip olabilir. NASA'nın Ekim 2024'te fırlattığı Europa Clipper aracının 2030'da Jüpiter'e varması bekleniyor.

Sources and further reading

Background reading: Europa (moon)
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