Volcanism in the Solar System Part 2 – Outer Solar System Justin Filiberto Lunar and Planetary Institute

Plan of Talk 1.Earth - review 2.Inner Solar System Mercury Venus Moon Mars 3.Outer Solar System Io Enceladus Titan Triton 4.Summarize Volcanoes in the Solar System

Outer Solar System  Only “rocky” volcanic body: Io  Other types of eruptions –Icy volcanoes –Geysers –?

Io  Moon of Jupiter  Mean radius (km) 1821 (0.286XEarth)  Mass (10 22 kg) 8.93 (0.015XEarth)  Surface T (K) 130  Gravity (m s -2 ) 1.8 (0.2XEarth)  Most volcanically active body in the solar system.

Evidence for Volcanism  Surface Changes  Gas Plumes

Loki Patera…  Active Lava Lake?

Ra Patera  Diameter-450 km  Height <1km  Area of Lava- 250,000km 2 250,000km 2  What type of volcano?  Lava type?

Ra Patera

Pele  Pele eruption lava >1350°C –Hawaiian lavas ~1000°C  Lava type?  Volcano?

Enceladus  Moon of Saturn  Mean radius (km) 251 (0.04XEarth)  Mass (10 20 kg) 1.1 (1.8x10 -5 XEarth)  Surface T (K) 75  Gravity (m s -2 ) 0.1 (0.01XEarth)  Icy Surface “Tiger Stripe” Ridges

Enceladus Erupts

Titan  Moon of Saturn  Mean radius (km) 2576 (0.4XEarth)  Mass (10 23 kg) 1.35 (0.023XEarth)  Surface T (K) 94  Gravity (m s -2 ) 1.4  Largest moon of Saturn  Only object with stable liquid on the surface (other than the Earth)

Icy Volcano?

Triton  Moon of Neptune  Mean radius (km) 1353 (0.2XEarth)  Mass (10 22 kg) 2.1 (0.0036XEarth)  Surface T (K) 38  Gravity (m s -2 ) 0.78  Surface is frozen nitrogen and water

Triton Cryovolcanism?  Bluish streaks – geysers of nitrogen?

Outer Planet Summary  Possible old volcanoes on Ganymede, and Europa similar to Enceladus?  Possible old volcanoes on Dione and Tethys?  Possible volcanoes on Pluto?  More data coming from New Horizons may answer some of these questions…

Some questions to ponder What types of volcanoes are common to the Earth only? Why? What types of volcanoes are common in the inner solar system but not the outer? Why? What does this suggest about the cooling histories of the inner planets? Outer planets?

Some questions to ponder From the volcanoes we have seen which ones would we expect on which planets? What do they suggest about other planets? Since most of us do not live near a volcano, how can students connect volcanoes on the Earth and other planets?