Who Gets a Choice? The Ethics of Generation Ships

The closest star to our Sun, other than the Sun itself, is Alpha Centauri -- and it's still 4.24 light-years away, so far that even light, the fastest thing in the universe, takes over 4 years just to get there. Using the fastest spacecraft humans have ever built, the trip would take more than 70,000 years. That's so long that no single person could make the whole journey -- which is why scientists have imagined a wild idea called a generation ship.

You will learn what a generation ship is and why it might be needed for interstellar travel. You will learn how many generations of people might be born and live their whole lives on board. You will learn what 'ethics' means and why generation ships raise hard questions. You will think through both sides of the biggest question: is it fair to send people who never got to choose?

A generation ship is a giant spacecraft designed to travel to a distant star over hundreds or even thousands of years, carrying not just one crew, but many generations of people who are born, grow up, and pass away during the journey. The people who first climb aboard would never see the destination -- it might take 20, 30, or even 100 generations before their far-off descendants finally arrive and step onto a new world.

For a trip lasting centuries, a generation ship would need to work like a small, sealed-off world. It would need to grow its own food using indoor farms, recycle its air so people always have oxygen to breathe, and clean and reuse its water again and again since no more could be delivered along the way. Engineers studying real generation ship designs, like the ones in Project Hyperion, have calculated that even a modest-sized crew would need thousands of square meters of farmland grown in layers to feed everyone for hundreds of years without any supply ships from Earth.

This is where ethics comes in -- ethics means thinking carefully about what is right and fair. The first crew of a generation ship could choose to go. But their children, grandchildren, and great-great-grandchildren born during the journey never got to choose anything. They would be born already living on a spaceship, with no sky, no ocean, and no way to ever set foot on Earth. Is it fair to make that decision for people who haven't been born yet? Some people say yes, because those future children would still have a full life, with air, food, friends, and purpose, just like life anywhere else. Others say it isn't fair at all, because nobody should be born into a locked spaceship without ever being asked.