What Are Black Holes?
What Are Black Holes? — an illustrated science story, set in Germany. 10 illustrated pages, free to read on Wonder Science.
Page 1
Sara and her father stood on the deck of the ferry churning through the foggy San Francisco Bay. "Look how Alcatraz just disappears into the mist," Sara said, pointing toward the dark island. Her father nodded, pulling his jacket tighter. "It's like a giant rock swallowing the world!"
Page 2
Back in the science lab at Everett Middle School, Sara sketched the foggy island in her notebook. "It made me think, Mr. Harris, could something pull in everything around it, even light?" Her teacher smiled, picking up a star chart. "You've just asked about one of the universe's greatest mysteries, Sara. We call them black holes."
Page 3
"The idea was so strange, it didn't start with a telescope, but with a pen and paper during a war," Mr. Harris explained. The classroom scene dissolved into a gritty historical setting. "We have to travel back to Germany in 1915, to a soldier thinking about the stars."
Page 4
"His name was Karl Schwarzschild, a brilliant physicist serving on the Russian front," Mr. Harris's voice continued. "While others were fighting, he was wrestling with a brand new, revolutionary idea from a scientist named Albert Einstein. Schwarzschild had been a prodigy, publishing his first astronomy paper when he was only sixteen!"
Page 5
Schwarzschild scribbled furiously in a notebook, a rare smile on his face. He looked up as another soldier entered the tent. "Look! Einstein said, 'A person who never made a mistake never tried anything new,' and I think I found something incredible hidden inside his new theory of gravity!"
Page 6
His math predicted that if a giant star collapsed, its gravity would become so strong that nothing could escape. "Not even light, the fastest thing in the universe!" Sara whispered in awe. "Light travels from the Sun to Earth in just 8 minutes and 20 seconds, but a black hole would trap it forever."
Page 7
For fifty years, it was just a theory. Then, in the 1960s, astronomers found a mysterious signal from space: a powerful, invisible beam of X-rays coming from a star in the Cygnus constellation. This invisible clue, named Cygnus X-1, was the first real evidence of a black hole gobbling up its neighbor.
Page 8
Back in the classroom, Sara tapped the X-ray section on the wall chart. "So they used the invisible light you showed us to find an invisible object! That's how they solved it!" Her father, who had come to pick her up, smiled. "Exactly! A cosmic detective story, finding clues nobody else could see."
Page 9
"The gravity is so intense, it bends light like a lens, creating a cosmic optical illusion," Mr. Harris explained. Sara's dad added, "And the material inside is unbelievably dense. A single teaspoon of a neutron star, which is what's left before a black hole forms, would weigh six billion tons!" Sara gasped, "That's heavier than every car on Earth combined!"
Page 10
"So a black hole is a spot in space where gravity pulls so much that even light can't get out," Sara summarized, writing it down. She looked at a poster of the Milky Way on the wall. "Mr. Harris, if there's a supermassive black hole at the center of our galaxy, why doesn't it just swallow the whole thing?"
About this story
- Location: Germany
- Audience: kids (ages 6–12)
Questions and answers
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