The total solar eclipse visible on Monday over parts of Mexico, the United States and Canada was a perfect confluence of the sun and the moon in the sky.
But it’s also the kind of event that comes with an expiration date: At some point in the distant future, Earth will experience its last total solar eclipse.
That’s because the moon is drifting away from Earth, so our nearest celestial neighbor will one day, millions or even billions of years in the future, appear too small in the sky to completely obscure the sun.
“We’ll only ever have annular eclipses,” said Noah Petro, a planetary scientist at NASA Goddard Space Flight Center, referring to “ring of fire” eclipses like the one that crossed the Americas in October.
But putting an exact date on Earth’s final total solar eclipse is a serious computational challenge involving a variety of scientific disciplines.
Persons:
it’s, We’ll, ”, Noah Petro
Organizations:
NASA Goddard Space Flight
Locations:
Mexico, United States, Canada, Americas