I immediately recognize the number. I’d worked it out back when I was studying Rocky’s clock. 7,776 is six to the fifth power. It’s exactly how many Eridian seconds it takes to wrap an Eridian clock around to all zeroes again. They divided their day into a very convenient and (to them) metric number of seconds. I can follow that.
“Eridian day.” I enter it into my dictionary. “A planet rotating once is a ‘day.’ ”
“Understand,” he says.
“Erid circles Eridani one time every 198.8 Eridian days. 198.8 Eridian days is ♫♩♪♫♪.”
“Year,” I say, and enter it. “A planet going around a star once is one year. So that’s an Eridian year.”
“We stay with Earth units or you get confused. How long is Earth day, question? And how many Earth days is one Earth year, question?”
“One Earth day is 86,400 seconds. One Earth year is 365.25 Earth days.”
“Understand,” he says. “I am here forty-six years.”
“Forty-six years?!” I gasp. “Earth years?!”
“I am here forty-six Earth years, yes.”
He’s been stuck in this system for longer than I’ve been alive.
“How…how long do Eridians live?”
He wiggled a claw. “Average is six hundred eighty-nine years.”
“Earth years?”
“Yes,” he says a little sharply. “Always Earth units. You are bad at math, so always Earth units.”
I can’t even speak for a moment.
“How many years have you been alive?”
“Two hundred ninety-one years.” He pauses. “Yes. Earth years.”
Holy cow. Rocky is older than the United States. He was born around the same time as George Washington.
He’s not even that old for his species. There are old Eridians out there who were alive when Columbus discovered (a bunch of people already living in) North America.
“Why you so surprised, question?” Rocky asks. “How long do humans live, question?”
“This is Earth gravity, question?” Rocky asks. His ball rests on the control-room floor next to the pilot seat.
I check the Centrifuge control screen. We are up to full rotational velocity and spool extension. The crew compartment has done the 180-degree turn correctly. The diagram shows the two halves of the ship at full separation. We are spinning smoothly in the void. The “Lab Gravity” value reads “1.00 g.”
“Yes. This is Earth gravity.”
He steps side to side, rolling his geodesic dome one face back and forth. “Not much gravity. What is value, question?”
“Nine point eight meters per second per second.”
“Not much gravity,” he repeats. “Erid gravity is 20.48.”
“That’s a lot of gravity,” I say. But that’s to be expected. He’d told me all about Erid before, including its mass and diameter. I knew their surface gravity had to be roughly double Earth’s. Nice to have my calculations verified, though.
And side note: wow. Rocky’s mass is 168 kilograms. That means on his homeworld he tips the scales at almost 800 pounds. And that’s his native environment, so I assume he can move around just fine.
Eight hundred pounds and can skitter around effortlessly. Mental note: Do not get in an arm-wrestling match with an Eridian.
“So,” I say, leaning back in the pilot’s seat. “What’s the plan? Fly into the Petrova line and get some Astrophage?”
“Yes! But first I make xenonite room for me.” He points down the hatchway toward the rest of the crew compartment. “Mostly in sleep room. But tunnels in lab and small area in control room. Is okay, question?”
Well, he can’t just stay in a ball forever. “Yes, that’s fine. Where is the xenonite?”
“Xenonite parts in bags in dormitory. Liquids. Mix. Become xenonite.”
Like epoxy. But really, really strong epoxy.
“Interesting! Someday I want to know all about xenonite.”
“I not understand science. I just use. Apology.”
“That’s okay. I can’t explain how to make a thinking machine. I just use it.”
“Good. You understand.”
“How long will your xenonite construction take?”
“Four days. Could be five days. Why you ask, question?”
“I want to work fast.”
“Why so fast, question? Slower is safer. Less mistakes.”
I shift in my chair. “Earth is in a bad state. It’s getting worse all the time. I have to hurry.”
“Not understand,” says Rocky. “Why Earth so bad so fast, question? Erid go bad slower. Have at least seventy-two years before big problems.”
Seventy-two years? Man, I wish Earth had that kind of time. But seventy-two years from now Earth will be a frozen wasteland and 99 percent of the human population will be dead.
Why isn’t Erid as badly affected? I furrow my brow. I only have to think for a moment before I have my answer: It’s all about thermal energy storage.
“Erid is much hotter than Earth,” I say. “And Erid is much larger with a much thicker atmosphere. So Erid has a whole lot more heat stored in its air. Earth is getting cold fast. Very fast. In fourteen more years, most humans will be dead.”
His voice becomes monotone. It’s a very serious intonation. “Understand. Stress. Concern.”
“Yes.”
He clicks two claws together. “Then we work. We work now! Learn how to kill Astrophage. You return to Earth. You explain. Save Earth!”
I sigh. I’m going to have to explain this eventually. May as well be now. “I’m not going back. I’m going to die here.”
His carapace shudders. “Why, question?”
“My ship only had enough fuel for the trip here. I don’t have enough to go home. I have tiny little probes that will return to Earth with my findings. But I will stay here.”
“Why is mission like this, question?”
“This was all the fuel my planet could make in time.”
“You knew this when you left Earth, question?”
“Yes.”
“You are good human.”
“Thanks.” I try not to think about my impending doom. “So, let’s collect Astrophage. I have ideas for how we can get some samples. My equipment is very good at detecting trace amounts—”