Top 5 Mysteries Of Our Solar System That Baffle Astronomers - Page 2 of 2

Here is a list of these 5 mysteries and the video does a great job of giving a quick background of each one:

5. The Venus Vortex

4. The Very Mysterious Lapetus

3. The Spider On Mercury

2. Plumes On Ceres

1. Io’s Out Of Place Volcanos

Here is a bit more on Io from wikipedia:

Io/ˈaɪ.oʊ/^[6] is the innermost of the four Galilean moons of the planet Jupiter. It is the fourth-largest moon, has the highest density of all the moons, and is the driest known object in the Solar System. It was discovered in 1610 and was named after the mythological character Io, a priestess of Hera who became one of Zeus‘s lovers.

With over 400 active volcanoes, Io is the most geologically active object in the Solar System.^[7]^[8] This extreme geologic activity is the result of tidal heating from friction generated within Io’s interior as it is pulled between Jupiter and the other Galilean satellites—Europa, Ganymede andCallisto. Several volcanoes produce plumes of sulfur and sulfur dioxide that climb as high as 500 km (300 mi) above the surface. Io’s surface is also dotted with more than 100 mountains that have been uplifted by extensive compression at the base of Io’s silicate crust. Some of these peaks are taller than Mount Everest.^[9] Unlike most satellites in the outer Solar System, which are mostly composed of water ice, Io is primarily composed of silicate rock surrounding a molten iron or iron sulfide core. Most of Io’s surface is composed of extensive plains coated with sulfur and sulfur dioxide frost