Jupiter is denser than water, yet composed for the most part of two light gases, hydrogen and helium. What makes Jupiter as dense as it is?

Jupiter's density can be attributed to a few factors:

1. Composition: While it's true that Jupiter is primarily composed of hydrogen and helium, which are both lighter than air, it also contains heavier elements like carbon, nitrogen, and sulfur. These elements are present in smaller quantities, but they contribute to the overall density.

2. Pressure: The immense gravitational force of Jupiter compresses its gases, increasing their density. The pressure at Jupiter's core is much higher than anything we experience on Earth, and under such extreme pressure, hydrogen behaves like a metal. This metallic hydrogen, which makes up a large portion of Jupiter's core, is much denser than the hydrogen gas we're familiar with.

3. Size: Jupiter is the largest planet in our solar system. Its size means that it has a strong gravitational pull, which compresses the gases it's made of, making them denser.

4. Temperature: The core of Jupiter is extremely hot, and this heat contributes to the density of the planet. The high temperatures cause the gases to move faster and collide more often, which increases the density.

So, while Jupiter is composed mostly of light gases, its size, the pressure at its core, and its temperature all work together to make it denser than water.