For the first time since 1979, North America will be treated to a total solar eclipse on Monday afternoon. But don’t worry tennis fans, the WTA’s stars—newly appointed “astronomers”—are sharing all you need to know about the rare event.

Three-time Connecticut Open champion Petra Kvitova, top seed Agnieszka Radwanska, Dominika Cibulkova and Kristina Mladenovic came together to provide a funny, yet important public service announcement for tennis fans.

As “Professor” Mladenovic said, “The moon will move between the sun and the earth, and this will block the sunlight from hitting the earth’s surface.”

In the northeast United States—at both the Connecticut Open and in New York, where US Open qualifying gets underway tomorrow—there will only be a partial eclipse. However, the sun will still be unsafe to look at without wearing eclipse glasses to protect your eyes.

Kvitova said it best: “Be safe.”

Obviously, the players in this video are not truly solar eclipse experts. For more info about the eclipse and appropriate cautionary measures, visit NASA’s Eclipse 101 page.