Epsilon Pegasi (Enif) - The Pendulum Double

[Moonshane]

Again inspired by TSAN the other night I looked at this double in my 6" scope at about 100x magnification. Amazingly the pendulum effect really does work well and is very obvious.

Tap the scope gently at right angles to the two stars and you'll see the primary move up and down as you'd expect but the secondary which is a lot fainter, bounces around as if held by elastic. Fascinating to watch.

Here's a link which explains why.

Epsilon Pegasi: The Pendulum Star