"Rarity"

I swear this will be my last memo about the eclipse. About a week before the big day, someone asked on my whiteboard what made this one so rare and special.

The deepest part of the moon's shadow touches the Earth about once every two years, but you may have noticed that most of the planet is uninhabited. The next total eclipse will occur on July 2, 2019. It will start east of New Zealand, cross through the southern Pacific over absolutely nobody, then slice across northern Chile and Argentina - cutting a path between Santiago and Buenos Aires - in the hours before sunset.

The next total eclipse here in Columbus won't occur until April 2024, where we'll be right at the edge of totality. A quick trip north to Mansfield or Cleveland will get you in view...assuming the clouds don't interfere. Carbondale, Illinois is especially lucky: not only were they near the point of greatest duration for this past one, but they'll also get a taste of the 2024 totality.

After that, Columbus won't get another chance at totality until 2099. So total solar eclipses are common...but also very, very rare.