Why is this video showing radio waves transmitted from a radio telescope? I saw this video at Space.com and I noticed that at 00:05 the animation illustrates waves propagating from space into The Dish at Parks Observatory, but at 00:50 the direction of propagation is reversed! Would there be some reason for transmitting - for example to create an artificial "star" for wavefront correction analogous to adaptive optics at visible wavelengths, or could it be simply a mistake in the animation?

Here are some GIFs from screenshots. You can check the video at the indicated times. 

circa 00:05



circa 00:50
I guess it's a mistake in the animation. At radio wavelengths turbulence doesn't affect the measurments anymore and above 200 MHz the ionosphere doesn't play a role yet, so I guess the notion of a guide star is unnecessary here.