When sending people to another planet, it’s probably more economically feasible to send a small number in today’s economics. But if you’re going to colonise a world around another star, you need enough people to establish the colony and provide a good, broad genetic base. So, just how many people is that?
There’s a variety of possible answers that I’ve been able to find, but looking at our own history, the number isn’t that high. There’s evidence that the supervolcano at Lake Toba in Indonesia erupted between 69,000 and 77,000 years ago and created a bottleneck in the Earth’s human population. That population is estimated to be anywhere between 2,000 and 20,000. This caused lower genetic diversity in the world’s people, even though we now have such a large variety of people. But consider this: the people outside of Africa are likely more closely related to each other than two random people in Africa. That’s because only a small number of people migrated out of Africa and populated the world. Europeans, Asians, Indians, Pacific islanders, and so on, are all more closely related than one person in Nigeria and one person in Namibia.
So, assuming that these numbers could provide a viable genetic base to ensure incest doesn’t happen, the initial population doesn’t need to be incredible high, but also shouldn’t be very low.
However, if this world is expecting more colonists to arrive, this argument is unneeded. But if this is a one time colonisation, we need a minimum number of people. If it’s several thousand, we need a pretty big ship.
On Ariadne, I don’t have the initial population, but there will be at least 5,000, and as many as 15,000. And this is on just one ship. Just to let you in on a secret, there will be two ships.
So, if you were to create a colony, how many people would you send?