 <a href="http://science.nasa.gov/headlines/y2008/16jun_moonillusion.htm" target="_blank" title="kasaitis1_strip.jpg"><img src="http://strangeattractor.co.uk/wp-content/uploads/2008/06/kasaitis1_strip1.jpg" alt="kasaitis1_strip.jpg" align="top" border="0" height="221" vspace="8" width="372" /></a>

This weekend sees Summer solstice and an almost full Moon. But why does it look so big?

NASA have a good <a href="http://science.nasa.gov/headlines/y2008/16jun_moonillusion.htm" target="_blank">page</a> discussing this illusion, which is still keeping scientists guessing.

Is it a trick of perspective - akin to the <a href="http://unmuseum.mus.pa.us/exmoon.htm" target="_blank">Ponzo illusion</a>? - perhaps, but then why do pilots report seeing it when there's nothing between them and the moon to generate false perspective?

Is it something to do with atmospheric magnification? Or perhaps the shape of the sky itself?

A big and ancient question, and one not best considered while staring at a screen – so get out there and watch the skies!

<a href="http://science.nasa.gov/headlines/y2008/16jun_moonillusion.htm" target="_blank">NASA</a>