David Kipping

And so there is a stable orbit.

It's kind of the outermost stable orbit you could have around the Earth.

Yeah, it's absorbing light.

It's possible to reconstruct.

I mean, to some degree we do this.

There's a technology called adaptive optics that can correct for what's called wavefront errors that happen through the Earth's atmosphere.

The Earth's atmosphere is turbulent.

It is not a single plane of air of the same density.

There's all kind of wiggles and currents in the air.

And so that each little layer is bending light in slightly different ways.

And so the light actually kind of follows a wiggly path on its way down.

What that means is that two light rays which are traveling at slightly different spatial separations from each other will arrive at the detector at different times because one maybe goes on more or less a straight path and the one wiggles down a bit more before it arrives.

And so you have an incoherent light source.

And when you're trying to do imagery construction, you always want a coherent light source.

So the way they correct for this is that if this path had to travel a little bit faster, the straight one goes faster and the wiggly one takes longer, the mirror is deformable.

And so you actually bend the mirror on the straight one down a little bit to make it an equivalent light path distance.

So the mirror itself has all these little actuators.

It's actually made up of like thousands of little elements, almost looks like a liquid mirror because they can manipulate it in kind of real time.

And so they scan the atmosphere with a laser beam to tell what the deformations are in the atmosphere and then make the corrections to the mirror to account for it.

That's amazing.