Aluminized insulation reflecting the sun.

https://en.wikipedia.org/wiki/Landsat_8

And sharp lines of reflection as there's nothing to diffuse the light from the sun which is why it's more sparkly than you may expect.

Those are so it can see where it's going

Satellite-headlights: because the space-streetlights keep floating away!

Satellites don't have lights. It must be reflection.

Especially a photographic sat wouldn't have lights, all it could do is light up nearby dust and debris and make it more visible.