How does the Webb Telescope orbit nothing (L2)?

It is a “Conical Pendulum” Orbiting the Sun

Imagine a basic conical pendulum. The bead goes in a circle around an empty spot. The centripetal force is provided by the horizontal component of tension, while its weight is balanced by its vertical component.

Now imagine a circular motion in empty space. Tension provides the centripetal force to go around the point. Earth goes around the sun the same way. The centripetal force is the sun’s gravity.

If you put them together, you can imagine Webb’s orbit around the sun and L2. It’s in a circular motion around the sun (elliptical, but almost a circle), but unlike Earth and the second case above, where the force (gravity here) lies on the plane of orbit, with Webb it is at an angle.

The component of gravity along the Sun-Earth line (x-direction) gives the centripetal force to go around the sun. The component perpendicular to that (y-direction) gives the centripetal force to go around L2, like a conical pendulum orbiting the sun.

Note

I had this question a month ago. I discussed it with a friend and came up with this explanation. The following video has a more rigorous analysis, but I think this version is more intuitive. YouTube video