While astronomers bicker over whether our solar system has 8 planets or 10—Does puny Pluto count? What about that upstart Xena?—here's a radical thought: Our solar system has only one true planet, and its name is Jupiter.
Jupiter's mass is greater than all the other planets combined and doubled. It is so enormous it could swallow 1,400 Earths. Everything else is pretty much debris in comparison. In short, if you want to understand what a planet is, you need to understand Jupiter. And yet, we don't. We've sent five probes whizzing past it and parked one in a long-term orbit around it, but we just keep running into bigger puzzles.
Take Jupiter's most famous feature, its Great Red Spot. The "spot" is actually a hurricane twice the size of Earth, and its color varies but is typically more of a salmon pink. Why pink? Planetary scientist Tony Del Genio of ...
