>From the web page: >http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/SEgeometry.html
"Eclipse geometry is complicated by the fact that Earth's orbit around the Sun is elliptical. As a result, the Sun's apparent semi-diameter varies from 944 arc-seconds at aphelion to 976 arc-seconds at perihelion. This 3% range in apparent size is, of course, quite indistinguishable to the naked eye."
