Whoever scheduled Sunday night’s total lunar eclipse knew what he was doing.

Most Sunday night lunar eclipses take place on school nights, way past bedtime for schoolkids trying to learn something.

Not this time, thanks to the Rev. Martin Luther King Jr., whose birthday is being observed Monday, which means that Sunday night isn’t a school night. Schools will be closed Monday, so a kid can stay up late, the time of day that lunar eclipses generally get booked.

Andy Fraknoi, an astronomy professor at the University of San Francisco, called the timing a happy “cosmic coincidence.”

The show starts at 7:34 p.m. with a partial eclipse. Slowly the Earth’s shadow will encompass more and more of the lunar surface.

From 8:41 to 9:43 p.m., the eclipse will be total — the entire surface of the moon will be in the shadow, and will glow a brownish “blood” red. The moon will then slowly emerge from the shadow until, at 10:51 p.m., the show will be done.

Regardless of any applause, there will be no encore.

Astronomers no longer regard eclipses as phenomena to study. Instead, they’re teachable moments. They’re opportunities to drag newbies into the astronomical tent and get them excited about turning away from their TVs and phones in favor of celestial programming, Fraknoi said.

“The eclipse is playing outdoors on every channel,” he said. “It’s big-screen entertainment.”

A total lunar eclipse, like the one Sunday night, can be seen from a given point on Earth once every couple of years or so. If you miss this one, you can tune in on May 26, 2021, or May 15, 2022, or Nov. 8, 2022, or March 13, 2025.

Tips for Sunday night’s eclipse If it’s cloudy or rainy (and it probably will be), tough luck. No rescheduling Bring a warm jacket, a chair and a thermos full of something hot. Lunar eclipses last up to five hours. Binoculars are better than telescopes. Ancient Incans thought lunar eclipses were caused by a giant jaguar eating the moon. If Neil Armstrong had been on the moon during a lunar eclipse, he would have seen a solar eclipse. Come back on May 26, 2021, for an encore. Also March 13, 2025.

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And unfortunately, that might be required, because the weather forecast for the Bay Area calls for rain and clouds at eclipse time.

There is an 80 percent chance of rain Sunday night and a 100 percent chance that it will be chilly enough to require a jacket. Even if it doesn’t rain, the eclipse may be playing behind closed doors, cloud-wise.

Eclipses, visible or not, are free. Eclipse-watching parties may not be.

Chabot Science and Space Center is hosting an eclipse party on its outdoor deck in the Oakland hills. Admission is $8 and includes hot chocolate. But eclipse fans take note — the event is sold out and “no tickets will be sold at the door,” according to the official announcement, even though there are no doors to the night sky.

Foothill College in Los Altos Hills will host a free eclipse watching party at its observatory, from 8 to 10:30 p.m., which means the college will start shutting down the eclipse party even before the eclipse itself is over. In addition, private telescopes will be set up in parking lot 4, in case rabid eclipse fans are hogging the main observatory telescope.

The Exploratorium in San Francisco is conducting the eclipse online, this being the 21st century. On the museum’s Facebook page, visitors can watch a telescope view of the moon, hear live commentary from Exploratorium scientists and listen to what the Exploratorium is calling a “special audio track that creates a generative musical composition based on a 3-D model of the moon, changing as the eclipse continues.” The actual museum, however, will be closed.

A lunar eclipse turns out to be a great opportunity to settle the raging debate about whether the Earth is round or flat.

Since a lunar eclipse is caused by the passing of the Earth’s shadow across the face of the moon, and since the shadow is curved, most people assume a lunar eclipse proves that the Earth is round. (Not everyone, however. According to the website of the Flat Earth Society, an eclipse is caused not by the round Earth at all but by a mysterious “shadow object” that “is never seen in the sky because it orbits close to the sun.”)

Fraknoi said that watching one lunar eclipse isn’t necessarily proof that the Earth is round — a flat Earth disc could have been at just the right orientation, relative to the sun, to cast a round shadow at any particular time.

“Watching only one lunar eclipse, you can’t really be sure that the Earth isn’t a giant pizza plate,” he said.

But since every single lunar eclipse in history has featured a round shadow, he said, there’s no other logical explanation than a round Earth. “The Earth really is round,” he said. “That’s been settled.”

A lunar eclipse is the more common, low-rent cousin to the far more spectacular solar eclipse, in which the moon passes directly between the sun and Earth, darkening the daytime sky, frightening animals and causing ancestors and panic-prone contemporaries to speculate that the world is coming to an end.

A total solar eclipse, like the one that occurred to great fanfare across the U.S. on Aug. 21, 2017, can be seen from a given point on Earth once every 350 years. It lasts for a couple of minutes, unlike a total lunar eclipse that can last for a couple of hours. Solar eclipses are big-ticket items.

In 2017, solar eclipse fans drove from the Bay Area to the middle of Oregon in order to be in the path of the total eclipse and snapped up special eclipse glasses to protect their eyes. On Sunday night, neither a trip to Oregon nor safety glasses is required. For eclipse watchers, or astronauts, the moon is more approachable than the sun.

Still, it looks like a little luck will be required at eclipse time. With every 80 percent chance of rain, there is a 20 percent chance of no rain. That’s a 1-in-5 shot. At the racetrack, ponies with longer odds than that come in all the time.

Steve Rubenstein is a San Francisco Chronicle staff writer. Email: srubenstein@sfchronicle.com Twitter: @SteveRubeSF