Science for Kids — August 16: Martian gems, dinosaur eggs, and water at the galaxy's heart

Professor Pip stood on a pretend-Mars — a bumpy patch of red dirt in the corner of his garden — and adjusted his slightly crooked spectacles. "Ah! Look at this, my friends. Rusty. Dusty. And full of surprises." He patted his bulging green lab coat pockets and pulled out a magnifying glass, a chunk of pale rock, and a very small flashlight.

Mia and Leo sat cross-legged in the dirt beside him. A little robot rover Pip had built out of cardboard beeped between them.

"On the real Mars," said Pip, his tail swishing behind him, "a NASA rover shone a laser at rocks that looked very boring. Grey. Pale. Uninteresting. And do you know what shined back?"

"A dinosaur?" Leo guessed hopefully.

"A gemstone," Pip whispered, eyes twinkling. He clicked on the flashlight and shone it through the pale rock in his paw. A tiny red-pink glimmer sparkled out the other side. Mia gasped.

"Watch closely," said Pip. "Light did the same thing on Mars. The rover's laser buzzed the rock — ZAP! — and the tiny bits inside the rock glowed a very special glow. Every mineral glows its own way. Scientists know each glow like you know your friends' voices from far away."

"So they heard the rock's voice!" said Mia.

"Precisely right!" Pip beamed. "And the voice they heard belonged to a mineral called corundum. On Earth, when a little bit of chromium sneaks into corundum, it becomes a ruby. If bits of iron and titanium sneak in, it becomes a sapphire."

Leo's mouth dropped open. "So Mars has rubies?!"

"Not big shiny ones you could hold," Pip laughed, "but teeny, tiny grains — smaller than a speck of sugar. And here's the wondrous part: corundum only forms when rocks are squeezed and heated to extremely big temperatures. Jezero Crater was made billions of years ago when an enormous space rock slammed into Mars and made a hole 45 kilometers wide."

"Like a giant hammer!" said Mia. "That would squish the rocks!"

"Exactly right! The impact could have cooked the ingredients that made the gems." Pip looked up at the wispy afternoon sky. "So a rock that looks boring on the outside can be hiding the memory of the day the sky fell down. Isn't that curious?"

He handed Mia and Leo each a small pebble. "Now you try. Find the most boring rock in the yard — and tell me what its story might be."

Professor Pip crouched in a sandy patch under a big old oak tree and swished his fluffy ringed tail with excitement. "Oh my whiskers, oh my whiskers," he whispered. He pulled a small brass fossil brush from his pocket and dusted at a smooth, oval, cream-colored rock half buried in the dirt.

Mia and Leo tiptoed closer, holding their breath.

"Is it a big pebble?" Leo asked.

"Look at the shape," said Pip, brushing very, very gently. "Round on one end, a little pointy on the other. Smooth shell. My friends… I think this is an egg."

"An egg?!" Mia squeaked. "Whose?!"

Pip's eyes got round behind his crooked spectacles. "In Argentina, scientists just found one just like this — and they think it belonged to a meat-eating dinosaur that lived seventy million years ago."

Leo did the math in his head. "That's… a really long time."

"Long enough that flowers changed colors, mountains rose up, and continents wandered around like slow big turtles," said Pip, patting the ground. "How does an egg last that long? Watch this." He pulled a peeled hard-boiled egg from his pocket — because of course he did — and set it on the sand. Then he sprinkled dry dirt over it, patted it down, and gently kicked more dirt over the top. Only the top of the egg peeked out.

"When a dinosaur egg is buried quickly — by a landslide, or a river flood, or a sandstorm — it gets sealed away from the air. No air means no bacteria can chew it up. Slowly, slowly, over millions of years, tiny bits of mineral seep in and take the place of the shell. That's called fossilization."

"Ohh!" gasped Mia. "Like sugar turning into a lollipop, one little bit at a time!"

"Precisely right!" Pip's whiskers twitched. "And here's the best part — the Argentina scientists think there might still be a tiny embryo curled up inside. That's a dinosaur baby that never got to hatch. If they can peek inside without breaking the egg — using a very careful X-ray called a CT scan — we might see the bones of a baby that was this close to being born."

Pip looked up at the sky. "Somewhere, seventy million years ago, a dinosaur mama tucked this egg into the dirt and hoped for the best."

He handed Mia and Leo each a smooth pebble. "Now you try — bury it, and imagine a scientist finding it seventy million years from now. What story would your pebble tell?"

Professor Pip stood on a hilltop at nighttime, patted his forest-green lab coat pockets, and pulled out his small brass telescope and a very small glass of water. His fluffy tail swished with delight.

"Curiouser and curiouser," he murmured. "Astronomers have found water — plain, ordinary water — hiding right next to a black hole."

Mia and Leo sat on a picnic blanket in their pajamas, staring up at the Milky Way stretched across the sky like a river of milk.

"But black holes are the hungriest things in space!" said Leo. "They eat light! How can water live near one?"

"That is exactly the question," said Pip, tail swishing. "The middle of our galaxy is a very spicy neighborhood. Millions of stars pack together. Radiation zips around like invisible fireworks. And in the middle sits Sagittarius A-star — a black hole four million times heavier than our Sun." He rolled the R for extra drama.

"So how did the water survive?" asked Mia.

"Here's how." Pip picked up an umbrella, popped it open, and held it over Mia. Then he sprinkled a pinch of glitter above her head. Most of it bounced off the umbrella and drifted to the grass. "The umbrella is like the shell of dust around a puffy old star called IRS 3. The star is dying, and as it dies, it puffs out layers of dust — like blowing bubbles in soap. The dust wraps around the star like a cozy blanket. Inside that blanket, it's calm."

"Ohh!" said Leo. "Like being under a table when it's raining!"

"Precisely right! Inside the dust shell, water molecules can hold hands and stay together, even though outside — whoosh — the black hole is roaring."

Pip lifted his little glass of water toward the stars. "And here's the wondrous part. When old stars die, they send their dust and water floating out into space. That dust and water become the ingredients for new stars. And new planets. Maybe even planets with oceans. Maybe even planets with red pandas someday."

"You mean the water in my hot cocoa," Mia said slowly, "might have come from an old star?"

"Every drop." Pip smiled at the sky. "Every single drop."

He handed each of them a paper cup with a little water inside. "Now you try. Take a sip — and say hello to a star."