STARLIGHTOn the outskirts of Hvalsø a clear evening was falling. Sigrun strolled over to where Tuuri was sitting on a rock, watching the darkening sky.
"Almost time to head inside, fuzzy head" she announced, plonking down next to the driver.
"Oh!" Tuuri jumped "I guess I lost track of the time." She gestured at the sky. "I was just looking at the stars."
Sigrun looked up. The first stars were indeed glimmering into view.
"Hmmm" she mused. "I guess that's one thing this flat country's good for. Back home the mountains block out most of the sky."
"The trees block out a lot of it in Finland" Tuuri replied "But you can get a good view over the lakes." She peered skywards "I've always liked stargazing".
"Seems a bit of a waste of time to me" admitted Sigrun. "The wagon's good for finding your way if you get lost, but apart from that..." she shrugged.
"That's okay" replied Tuuri. "When I was a kid I found a book all about the stars and constellations. I spent ages learning them all, and then when..." she paused for a moment before continuing. "When we had to move to Keuruu and everything was different, the stars were about the only familiar things." She gestured upwards. "Even here in the Silent World they're still the same."
Sigrun studied the darkening firmament "I never thought about it like that".
"They're almost like old friends"
"Hmmm"
Sigrun gazed off at the horizon. "What's that big red one?"
Tuuri thought for a second.
"That's Arcturus, in the constellation of the Bear Guard."
"Really?"
"Yep"
"How about that?"
The two sat in silence for a while, watching as more pinpricks of light sparked to life. Eventually Tuuri spoke up.
"It's strange to think some of them might not be there any more."
"What?" Sigrun's brow creased.
"The stars. Some of them might have burnt out by now, but we wouldn't know."
Sigrun stared at her in puzzlement "Stars can burn out?"
"Well, yes. They burn for millions of years, but eventually they die. But it takes so long for their light to reach us that we could still be seeing it for centuries afterwards."
Sigrun considered this.
"Light takes time to travel?"
Tuuri laughed.
"Yes! It moves really fast - really really fast - but it still takes time. And the stars are so far away that we're seeing them as they were hundreds of years ago."
"Hmmm" Sigrun rubbed her chin thoughtfully "That's... that's a lot to think about..."
Tuuri smiled.
"I guess so!"
"Yeah" Sigrun got to her feet. "Anyway it's time to turn in. We need to get going at first light tomorrow."
The pair wandered back to the tank, leaving the night to the stars.
* * * *
The following day dawned bright and sunny, which at least made the job of carefully coercing the tank along a particularly obstructed section of roadway near Nyrup somewhat easier. Tuuri was just inching it past a particularly inconveniently positioned tree trunk when Sigrun entered the cabin, plonking down on the passenger bench.
"I've been thinking about what you said about light" she announced.
"Uh-huh" Tuuri responded, switching to a lower gear and gunning the engine.
"You said light takes time to travel, right?"
"Yeah" Tuuri confirmed, wrestling with the wheel as gravel bounced noisily against the tank's underside.
"Well that got me thinking about looking at a clock."
"A clock?" Tuuri heaved the wheel hard to the right just in time to stop the tank toppling into a previously concealed roadside ditch. Sigrun scrabbled at the dash for balance, but continued.
"Yeah. When you look at a clock, the hands go around. But I thought what if you could move away from a clock at the same speed as light? You'd see the hands stand still, right?"
Tuuri's brain finally caught up with her ears. Her brow furrowed.
"I guess..?"
"And then if you moved away
faster than light, you'd see the hands go backwards and you'd be looking into the past!"
Tuuri's brow furrowed further.
"Well... I suppose you would. But it's impossible anyway."
Sigrun's brow took its turn to furrow.
"How come?"
"Well, nothing can travel faster than light"
Sigrun tilted her head to the side and pursed her lips in thought.
"Why not?" she finally queried.
Tuuri let go of the wheel for a second to shrug.
"That's just the way it is. Light is the fastest thing there is and nothing can go faster than it."
"Oh." Sigrun frowned. "What if you had something
really fast. Like one of those jet planes the old timers had?"
Tuuri shook her head.
"Nope. Not even they were fast enough."
"Oh." Sigrun stared out the window for a few seconds. "So you can't look at the past then?"
"I guess not" Tuuri turned her attention back to the road. "Good thinking though."
Sigrun sat in silence for several minutes, watching the landscape roll slowly past.
"What if you could slow light down!" she suddenly exclaimed.
Tuuri - whose attention had returned to the road - jumped, jerking the wheel and sending something clanging to the ground in the back of the tank. A distressed yowl and muffled Swedish swearing floated into the cabin.
"What?!"
"What if you could slow light down so you could catch up with it!" repeated Sigrun "Then you could look at the past!"
"Ummm..." replied Tuuri, regaining control of the wheel and marshaling her thoughts. "That's another clever idea, but you can't slow light down. That's one of the other things about it - light always moves at the same speed, no matter what."
"Really?"
"Yeah"
Sigrun thought for another minute.
"Light is
weird"
* * * *
The team set up camp that evening in a patch of woods near an old railway line. As Mikkel got to work heating up something that could charitably be described as stew, Sigrun wandered over to where Tuuri sat on a log, looking through an antique book retrieved from the tank's cargo compartment.
"So I've been thinking about what you said about light always moving at the same speed" she started.
Tuuri sighed quietly and put the book down.
"What about it?" she asked.
"It has some really wild implications!" Sigrun exclaimed, taking a seat next to her.
"Such as?"
"Okay" Sigrun began, leaning in conspiratorially "You'll have to bear with me because this gets complicated."
"Okay..."
"So, imagine you fire a rifle, the round shoots out at, like, 100 kilometres an hour..."
"Um... I think bullets travel much faster..."
"But then imagine you're standing on top of one of those Swedish trains that go 500 kilomteres an hour..."
"Actually the trains are a lot slower..."
"And
then you fire the rifle forwards, the speeds add up and the round goes 600 kilometres an hour, right?"
Tuuri considered. "I guess so..."
"Yeah!" Sigrun continued "But imagine you were inside the train and the track was
really smooth so you didn't know you were moving, you'd say the round was still only going at 100 kilometres an hour!"
"Okay..."
"So the speed of the round depends on whether you're seeing it from inside or outside the train!"
Tuuri cocked her head. "Not really, I mean it's still
really going at 600 kilometres an hour..."
Sigrun ignored her. "Yeah! It depends where you're looking from! But what if it's
light?"
"If... if what's light?"
"The round! What if you weren't firing a round from a rifle, you were shooting light out of a flashlight?"
"I don't quite..."
"It doesn't work!" Sigrun exclaimed, leaping to her feet. "If you look at the light from outside the train it looks like it's moving at one speed, but from inside the train it looks like it's moving at another! Which you said is impossible!"
"Uh...""
"But you
can use flashlights on trains, so it
has to work somehow! And the only way it can work is if the train changes length!"
Tuuri stared at her like a hedgehog caught in a spotlight.
"What?" she managed to squeak.
"It's the only thing that makes sense!" Sigrun waved her arms dramatically "The train has to be shorter!" she paused for a second "Or maybe it's longer? Anyway, the train has to be a different length for the person in it and the person looking at it!"
"But... that doesn't make sense..."
"Of course it does!" Sigrun declared "It's the only thing that
does make sense!"
"What makes sense?" asked Mikkel, approaching with two steaming bowls of stew.
Sigrun turned with a grin.
"I was just explaining to fuzzy head here that if light always moves at the same speed, then lengths have to change whenever you look at anything!"
Mikkel stopped and stared at Sigrun for a moment.
"And you... read this somewhere?"
"Read it?" Sigrun laughed "No! It just stands to reason!"
Mikkel looked at Tuuri who was frozen somewhere between bewilderment and existential terror.
"Sigrun... are you familiar with the works of Albert Einstein?"
"Who's that?" she asked.
Mikkel inhaled thoughtfully.
"Nobody important" he finally declared.
In the sky above the stars shone on.
