It's a wonder of nature -- marveled at, by cultures around the world.
"We're going to see a partial solar eclipse and the moon is going to move between the sun and the earth and it's going to block out 84 percent of the sun," Exploratorium senior scientist Paul Doherty said.
Doherty says in the Bay Area, the eclipse will look something like a "bright letter 'C.'"
Staring at the sun is dangerous, so Doherty already has his special eclipse glasses ready. You can buy them at a telescope shop.
"They're Mylar coated with aluminum on both sides; they're designed to save your eyes," Doherty said.
But you don't have to look at the sky to see the partial eclipse this weekend. In fact, you can see the eclipse just by looking at the ground near a tree.
"Every pinhole in that tree is going to make a letter 'C' on the ground and it'll just be an amazing sight," Doherty said.
Doherty showed ABC7 News how it will work using a piece of paper and a light bulb.
"I've cut an aluminum mask that's going to look just like the sun's going to look during this partial solar eclipse," he said.
Holding up a piece of construction paper with a hole in it, a letter 'C' shines on the wall.
So no matter what the shape of the gaps between all these leaves, you'll be able to 'C' the partial eclipse in all of them.
"And when they blow in the wind, the 'C's' stay in the same position because the sun's not rotating in the sky," Doherty said.