When a volcano erupts on Earth, its plume of ash can spread across thousands of miles. The strongest eruptions can blanket the entire planet, affecting the climate for months or years.

Eruptions on Jupiter’s moon Io are felt far beyond the moon itself. Some of their material escapes and forms a doughnut-shaped ring around Jupiter. That contributes to radiation belts that would be strong enough to kill an unprotected astronaut in hours.

Io is the most volcanically active body in the solar system. Hundreds of volcanoes dot its surface. They produce pools of lava that sizzle at more than 2,000 degrees Fahrenheit — much hotter than lava on Earth.

Some of the eruptions are so powerful that they shoot gas hundreds of miles high. Ultraviolet radiation from the Sun zaps some of this material, giving it an electric charge. Jupiter’s magnetic field then grabs the charged particles and sweeps them all the way around the giant planet, forming the ring.

This ring is so powerful that it can easily damage a spacecraft. So Jupiter missions use radiation-hardened components, and they avoid the ring as much as possible. And if people ever visit Jupiter, they’ll need good shielding to survive a plunge through Jupiter’s volcano-enhanced radiation belts.

And Jupiter is quite near our own Moon tonight. It looks like a brilliant star just to the right of the Moon. Through binoculars, Io and three other large moons look like tiny stars quite close to Jupiter.

Script by Damond Benningfield