Isabel opened her suitcase and started to unpack.
Her father had already left for a meeting.
"This is going to be so boring," she mumbled.
"How can you have fun when it's dark and cold all the time?"
Isabel and her father lived in Florida.
But for the next month, her father was working at a university in Tromsø, Norway.
The city was north of the Arctic Circle, and they had arrived during the polar night.
Because of Earth's tilt, polar regions receive almost no sunlight during this time.
In Tromsø this lasts from November through January—three whole months!
Just then Isabel heard a knock.
It was the university student who lived next door.
"Hello," Erik said with a friendly smile.
"Ready for your tour of Tromsø? Dress warmly—it's cold outside!"
Isabel forced a polite smile in return.
"Ugh," she thought. "Right now my friends are probably at the beach!"
Isabel followed Erik as he pointed out restaurants, theaters, and shops.
She spotted a group of kids wearing ski gear.
"Are they going skiing?"
Erik grinned. "Why does that surprise you?"
"It's dark outside! Isn't it dangerous to ski now?"
"There are lights on the slopes. And it's fun to ski at night!"
"What else can you do during the polar night?" Isabel asked.
"Well, many people go to concerts and cook meals together.
People like to go ice fishing and ice skating.
We can even feed reindeer."
Isabel laughed. "I could never do some of those things in Florida!
But it must be hard to live with so little sunlight for three whole months."
"Some people find it difficult.
They use special light boxes that give the effect of the sun.
Other people take vitamin D pills.
Not getting enough sunlight can cause a lack of vitamin D."
Erik shrugged. "I love the polar night."
"What's summer like?"
"Great," Erik said.
"From May to July, we have the midnight sun.
It stays light all day long.
You can go hiking or swimming in the middle of the night."
They went into a cafe to get warm.
"So, what would you like to do while you're here?" Erik asked.
"Actually . . ." Isabel took a sip of her steaming hot chocolate.
"Everything sounds fun!"
Isabel's month in Tromsø flew by.
She went skiing and ice fishing.
She sledded down snowy hills!
On her last night in Norway, Erik came by.
"I have a surprise," he said.
"We're going to drive outside the city for a show."
Forty minutes later Erik pulled into a parking lot.
They got out of the car and followed a trail to a dark field.
People were standing there, staring up at the sky.
"Whoa!" Isabel gasped.
Waves of green light danced above. "The northern lights!"
Erik grinned. "They're caused by particles from the sun entering Earth's atmosphere.
You can see the show best when you're close to the North Pole."
Soon they were driving back to Tromsø.
"Ready to return home to warm, sunny Florida?" Erik asked.
Isabel shook her head.
"Nope! I love the polar night. It's beautiful—and fun!"