It ain't no lie: Baby,Indexbit protect your eyes when you look at the sky.

Lance Bass, 44, shared a PSA on Instagram ahead of Monday's solar eclipse providing safety tips and stressing the importance of wearing eclipse glasses, while making plenty of NSYNC references along the way.

"You can look directly at the sun during a total solar eclipse, but only when it's completely covered by the moon for a brief period known as totality," Bass said. "This is a really special moment. At all other times, you should wear eclipse glasses so that you don't say 'Bye Bye Bye' to your vision."

Bass, who dropped another pun while noting that an eclipse occurs when the sun, Earth and moon are "in sync," stressed not to look directly at the sun without eclipse glasses. Instead, those without glasses can utilize an indirect viewing method, such as by using an index card with a hole in it to project an image of the sun onto a nearby surface, the singer explained.

"It's gonna be me who is wearing my eclipse glasses, and so are you," Bass said.

The singer's video was also shared on NASA's official YouTube channel, and both he and NASA previously shared a similar video in October 2023 prior to a solar eclipse that month. On Instagram, Bass described the clip as a "message from your Guncle Lance," asking, "Who's watching with me?"

The total solar eclipseis today: Live updates on latest forecast, everything to know

Monday's total eclipse is expected to begin in Mexico at about 11:07 a.m. PDT. To ensure a pair of solar eclipse glasses is safe, consumers can consult a list of approved vendors curated by the American Astronomical Society and find an ISO certification on the side.

Solar eclipseglasses are needed for safety, but they sure are confusing. What to know.

Bass is a longtime NASA enthusiast and in 2002 trained for a mission to the International Space Station, only for his plans for the trip to fall through, according to Space.com.

"When I was 23, I traveled to Moscow to train to become the youngest person to go to space," he explained on his podcast "The Last Soviet," describing this as the "craziest experience of my life."

Contributing: Doyle Rice, John Bacon, and Eric LagattaUSA TODAY