Project Hail Mary

by Andy Weir

Hmm. I think mostly in metric when doing science stuff. Interesting. Most scientists do, though, right? Even scientists who grew up in America.

I stood in front of a bunch of kids and taught them basic science. Because what’s the point of even having a world if you’re not going to pass it on to the next generation?

It had taken me years to cultivate a rep as the “cool” teacher. Kids are smarter than most people think. And they can tell when a teacher actually cares about them as opposed to when they’re just going through the motions. Anyway, it was time for the lightning round!

“They’re wrong!” I crossed my arms. “There’s nothing magical about hydrogen and oxygen! They’re required for Earth life, sure. But another planet could have completely different conditions. All life needs is a chemical reaction that results in copies of the original catalyst. And you don’t need water for that!”

There is no time for slow, international committees. The sun is dying. We need a solution. It’s my job to find it.”

After about 3,000 degrees Celsius, the hydrogen and oxygen atoms can’t stay bound to each other anymore. The surface of the sun was 5,500 degrees Celsius.

The consumption rate was 6.045 grams per

second before. So it’s gone down a little bit. And the fuel amount went down too. Basically, as the fuel gets consumed, the total mass of the ship goes down, so it needs less fuel per second to maintain the constant acceleration. Okay, that all makes sense.

When light hits gas molecules, the electrons get all worked up. Then they calm down and re-emit the energy as light. But the frequency of the photons they emit is very specific to the molecules involved. Astronomers used this for decades to know what gases are out there far, far away. That’s what spectroscopy is all about.

Light is a funny thing. Its wavelength defines what it can and can’t interact with. Anything smaller than the wavelength is functionally nonexistent to that photon. That’s why there’s a mesh over the window of a microwave. The holes in the mesh are too small for microwaves to pass through. But visible light, with a much shorter wavelength, can go through freely. So you get to watch your food cook without melting your face off.

“Yes,” she said. “They found a collection of genes that give a human ‘coma resistance.’ That’s what they’re calling it. The sequences are in what scientists used to think was junk DNA. But apparently it’s something we evolved a long time ago for some unknown reason and still lurks in some people’s genetic code.”

I catch a glint of the cylinder. Every now and then the flat ends of the gently tumbling cylinder reflect Taulight. I’ve decided “Taulight” is a word, by the way. Light from Tau Ceti. It’s not “sunlight.” Tau Ceti isn’t the sun. So…Taulight.

That’s the message. “We’re from the 40 Eridani system. And now we’re here at Tau Ceti.” But there’s even more to it than that. They’re also saying “40 Eridani has a Petrova line, just like Tau Ceti.”