According to the principles of gravity, the direction we call "down" on Earth always points towards what?

A fixed point in the solar system

The direction opposite of the sun

A student claims that people in Australia should fall off the Earth because they are on the "bottom" of the globe. Why is this idea incorrect?

The Earth's rapid rotation creates a centripetal force strong enough to hold everyone on the surface.

The magnetic field of the Earth is what holds everything on the surface.

Gravity pulls them toward the Earth's center.

The atmosphere is thick enough to prevent people from falling into space.

In the same universal direction as "down" on Earth

The direction of "down" is relative and depends on the nearest large source of gravity.

All objects in space are in zero-gravity environments, so there is no "down".

The rotation of the galaxy provides a universal "up" that scientists use for navigation.

The concept was disproven because astronauts in orbit float, which shows that the direction of down changes unpredictably from moment to moment.