You may have heard all the excitement last weekend about the so-called "supermoon". The gist of it is that the moon's orbit is not perfectly circular, so its distance from the earth varies slightly. But all the talk of the "SuperMoon" got me thinking and I realized that we were missing a teachable moment. No, the moon being at perihelion is not a big deal, but our Moon is pretty "super". Let me show you why:
The "Supermoon" of March 19, 2011 (right), compared to a rather "average" moon of December 20, 2010 (left): note the size difference. Images by Marco Langbroek.
You may have heard all the excitement last weekend about the so-called “supermoon”. The gist of it is that the moon’s orbit is not perfectly circular, so its distance from the earth varies slightly. When it is at the closest point in its orbit, it looks slightly larger (and therefore slightly brighter) in the sky. It’s not really a big deal, and all the talk of the SuperMoon got many astronomers worked up in much the same way we get worked up about the Mars Hoax or the 2012 doomsday.
But all the talk of the “SuperMoon” got ...