The question nobody’s asking about space colonization

I think it's an interesting question to ask. Why do we actually want to look for these worlds? Why

do we want to maybe even one day visit them and colonize these exoplanets in the far future

For me, I think what we're doing right now is a bit like being the map makers. If you go back 400

500 years, we really didn't know what the shape of the globe was or where the continents were

and people were voyaging out into the unknown and drawing the first maps of what might be out there

And I think a lot of what we're doing right now is kind of similar as astronomers. We are map makers, essentially. We are looking out and trying to draw not the continents, but the maps

of the exoplanets that our distant descendants might one day visit and perhaps even build colonies on

How to colonize a galaxy. Now the question is, why do we have this urge? I think it's something fundamental to us as human

beings. Ever since we left Africa, we've had this compulsion to explore, to go over the next hill

over the next mountain, cross that river and see what might lie beyond. There is the promise of a better life, more resources

building a more advanced civilization. That call for exploration is somehow just built into our spirit, I think

to want to do this. Ultimately, there is a practical reason for doing it as well

which is, of course, having all of our eggs in one basket here on the Earth is a fairly risky strategy

It would only take one giant asteroid to strike the Earth and knock us all out of existence

or of course it could be a gamma ray burst or a supernova

The universe has no shortage of ways of exterminating life on the earth

And so if we can put our presence on other worlds, it perhaps gives us a better chance of survival

However, one thing we have to be very cautious with, with this idea of expanding human presence

is of course there could be living creatures or even living beings, civilizations out there on these worlds already

And we really don't have any more right than they do to put our presence out there onto these worlds

especially if there's someone already there. So there is interesting ethical questions

about how we should actually conduct ourselves in such an exploration phase

If we want to explore beyond our solar system and visit even the nearest exoplanet to us which is Proxima Centauri b 4 light years away it would take even our fastest spacecraft many thousands of years to cross that distance using

chemical propulsion technologies, which is what we have relied on so far. These distances are so

great compared to human technologies that there's no way a human lifetime could ever last long

enough to survive the journey and expect to step foot on the other side on these planets

So how do we solve this problem of one day visiting these other worlds

Is there a way that we could get over chemical propulsion and reduce that journey from thousands of years to maybe decades or even years

Now, unfortunately, we can't really think of a way of doing that with a human being on board

but we can think of ways of doing that with very small spacecraft, even micro spacecraft

So there was ideas to use solar sailing or even really light laser sailing to push a spacecraft not only to nearby planets in the solar system, but beyond to exoplanets many light years away

The idea here is to have a very, very light spacecraft. Think of an aluminum sheet that is just maybe even 20, 100 atoms thick, a very, very thin sheet of material

And yet it is huge, maybe many meters across. and you shine a gigawatt laser at that large sheet of aluminum

it will be propelled by light pressure to very high velocity. Now, of course, the payload is going to be very small

We're talking about a microgram payload on board this thing. That's going to be something like a very small chipset essentially on board

It's not going to be able to do a lot, but it could probably take a photo. It could probably have an AI chat GPT loaded on board

that could maybe interact with people on the other side. But the idea of putting a human being on board one of those things is completely impossible

Just the mass of a human is far too heavy for these vehicles to work in that way

So I think the most realistic proposal I'm aware of, of getting a human being to actually physically step foot on another exoplanet within sort of 100 years timescale

would probably be you don't actually have a human being on board the spacecraft. Instead you just have embryos frozen embryos that perhaps are even genetically engineered to be well suited for the destination planet they arriving at Now of course there has to be something on board that going to unpack those embryos and grow them into human beings

And so you can imagine having a robot on board that would accomplish that goal

In fact, this idea was recently explored in Ridley Scott's Raised by Wolves series

And I think it is most realistically the best way I can imagine of seeing a human being on another exoplanet in, let's say, the next century

It's difficult to imagine exactly what an astronaut arriving on an exoplanet is really going to expect

because after all, with our current technology, we only have very limited information about what these exoplanets are truly like

We know their mass, their size, we know their chemical composition, but we don't truly know much more beyond that

So what are the things they might encounter? One of the problems might be there might not even be a solid surface on these worlds

There are these types of planets which are in between the size of the Earth and Neptune

We sometimes call them super-Earths. We sometimes call them mini-Neptunes. But really, we don't know

They could have a non-solid surface, which would obviously be a challenge for astronauts

to build a colony in the way that we would normally recognize. On top of that, we don't even know really what the conditions would be like for an astronaut

in terms of the gravity or the terrain. The gravity could be much stronger than that of the Earth

Of course, on the Earth, we have one g of gravity. And if you go into an airplane and you're a fighter pilot, you experience maybe two

three, four g's of pressure on your body. and that's fine for a few seconds but to live that way would be extremely stressful for the

human body. I can't really imagine a human being coping with four g's of gravity for a prolonged

period of time. On an exo moon there'd be other challenges of course. You would have this beautiful

giant planet potentially in your sky many many times larger than we see the moon in our own sky

It would mean at night time there really wasn't a night time. You'd still have essentially a kind

of afternoon level of light even during the middle of the night because of all the reflected light coming off your giant exoplanet around you

And that would raise some interesting questions about potentially what the biosphere itself would be like

Would animals have developed to live differently to nocturnal creatures on our own planet

It could be a very hazardous place to be an astronaut if we not very careful But this is the human spirit to go to a new place explore sure you know the people who are willing to do that will be very aware that they taking a huge risk and

are probably accepting of that risk because that's something built into us at least some of us to

want to go to those places and take the risk anyway. One of the interesting cultural questions

about a civilization which spreads out between the stars is that space is very very big in fact if

you spread out far enough you could end up on one side of the galaxy to the other which is a hundred thousand light years across. So that would mean that simple messaging, limited by the speed

of light, would take a hundred thousand years. It's very difficult to imagine how a culture could

remain monolithic over such a long distance, that in fact these cultures would splinter off and

perhaps even forget their origins as is often explored in the sci-fi books and the movies Dune

where civilizations really aren't sure where the original planet even is anymore. So I think a

question we often have when we think about the looking for aliens is that we kind of assume

there'll be a monolith. We'll assume they'll all act the same way, but truly, even if they spread

out from a singular source, the sheer distance scale will ultimately force them to fracture into

a diverse range of civilizations and cultures. And that's interesting when we think about looking out

that we're not going to encounter just maybe one single galactic federation, but really a menagerie

of different beings. Personally, I think the idea of humans expanding and colonizing other planets is feasible

in our own solar system, but is a stretch to imagine really happening

for exoplanets just because of the sheer distance to them. The sheer challenge of traveling that long in space

with a human body is gonna be very difficult to imagine overcoming

I'll never say never, but just it's not my bet that that would be a likely thing to happen

But I do think I can imagine a human presence across the solar system in the far future

and having an extended human presence in the form of AI agents, robots and machines

children, if you like, spreading out to those more distant outposts and sending us back information

and being ambassadors to the greater part of the galaxy. Want to support the channel

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