Other Planet's Radiation Belts.

[William Thompson]

The Van Allen radiation belts exist because the Earth's magnetic field traps the solar wind. I wonder of other planets in our solar system share such a feature. The only reason I am thinking about this is its impact in the likelihood of finding ETI on extra-solar planets.

I recall that the findings from the Viking mission were disappointing in the sense that they determined that Mars is too bombarded by radiation for life. I wonder what has been discovered about Venus. I know because of other environmental issues there is no life there. But I wonder if it has this sort of radiation belt around it.

 

[daveb]

The Van Allen belts are a result of the hunk o' metal at the Earth's center spinning (a moving electric charge induces a magnetic field). I believe only the terretrial planets (Mercury through Mars) and a few moons are known to have metal cores, though I'm sure someone else can verify this. I'm not sure if any of the gas giants have metallic hydrogen at the core, though.

 

[DaveC426913]

According to http://www.nineplanets.org/jupiter.html" , "Jupiter probably has a core of rocky material amounting to something like 10 to 15 Earth-masses.

Above the core lies the main bulk of the planet in the form of liquid metallic hydrogen. This exotic form of the most common of elements is possible only at pressures exceeding 4 million bars, as is the case in the interior of Jupiter (and Saturn). Liquid metallic hydrogen consists of ionized protons and electrons (like the interior of the Sun but at a far lower temperature). At the temperature and pressure of Jupiter's interior hydrogen is a liquid, not a gas. It is an electrical conductor and the source of Jupiter's magnetic field. "