# How often do partial solar eclipses of 90% of totality occur in same place?

I know that the mean interval between total eclipses in a single place is about 375 years, which is not surprising given the small band of area of the totality. However, the penumbra of the eclipse partially shadows a much larger area than the totality:

Image Credit: NASA Scientific Visualization Studio

If we were to take a wider area, such as the band of 90% coverage, how many years would there be between eclipses at a single place on average?

• Interesting question, and cool graphic! Where did that image come from by the way? It's usually good to cite the original source. – uhoh Mar 5 '18 at 10:34
• As a Q&D approach, take the width of the totality band, divide by the width of the 90% band, and multiply 375 years by that ratio. I'm not posting as an answer because it feels like too much of a hack. – Carl Witthoft Mar 5 '18 at 16:11