If the human race were to leave Earth, what would be the likeliest planet to move to?

Question

Stephen Hawking said recently that if the human race were to survive then we would have to leave this planet before it is destroyed by a meteor, nuclear war or the death of the Sun. What planet would we go to? How far away is it? And how long would it take to reach it?

Answer 1

We could terraform Mars and probably Venus and make them liveable if we really wanted to. And, we could set up colonies and humans could live there and raise families. However, if you're talking about mass emigration, e.g. the relocation of humans to another planet, that's a completely different question.

Think about this. The largest ocean vessels we can build today are the Nimitz-class aircraft carriers. They carry a crew of 5000. Without the aircraft and supplies, they could carry 10,000 to 12,000.

Let's assume that we could build a space craft capable of moving 10,000 people from Earth to Mars and that we have 1000 of them. And, let's assume that it takes a month to make the round trip.

1,000 ships x 10,000 people x 12 months = 120 million people per year.

There are 6.6 billion people on Earth.

6.6 billion / 120 million = 55 years

So, it would take 55 years to move our population to Mars. It just isn't feasible to move humans elsewhere on an emergency basis as you suggested. Think how much fighting there would be to get on one the ships.

We would need a number of very advanced technological breakthroughs to make it happen. Examples: room-temperature superconductors, propellant-less (gravitic?) propulsion.

If you are on Earth when the giant comet or asteroid hits, you're just doomed. Colonies on other planets would be our insurance policy against loss of our species, but not the loss of our individual lives.

Answer 2

Our preference would be the nearest Class M (Minshara Class) planet in Star Trek term, we want the nearest Class M with the nearest similiarity to Earth.

No other Class M planet have been found beside Earth.

I suggest we build Earth II as a back-up planet. Building Earth III, Earth IV, and so on are also good.

If meteor and the death of the Sun threaten Earth, why not just move the Earth?

War? Let the war cool down, then rebuild the Earth.


Now if it's a 'temporary evacuation', then it's our 'small' spaceships that we would move to. Reactivating the Moon back into active service would be an option.

It's around 380.000 kilometers away from Earth and took 3 days of travel under current official travel.



Note, we already a one race species. Also if a group of humans go to the Moon and start a race there, wouldn't the Moon Race want to return back to Earth if Earth suddenly become preferable again?

Answer 3

Mars is the first choice. Venus is too hot, and has a sulfuric acid atmosphere - totally inhospitable to life. Mars is cold, but nuclear reactors could be placed there for heat and power. Some kind of shielding would have to be in place to protect the people from the rare radiations that affect the place, and we don't know enough about them yet to know how to do that. Eventually, even Mars would have to be abandoned, because the sun will eventually go to a "red giant" phase in which it will become so big it will encompass the orbit of Mars, frying everything to a crisp. The nearest star system is Alpha Centauri, which is 4 light years away. Another choice within our solar system might have to be one of the moons of Jupiter, which theoretically could be "terra-formed", but with the sun gone to a "white dwarf" state (after the red giant phase) we would probably have to go to another solar system if we wanted to live on a planet, and not in space ships.

Answer 4

The likeliest place, not planet, would be the Moon....it's certainly the stepping stone. I would imagine that half a dozen or so families would be allowed to colonize the moon for a few generations or so......babies born there would in time evolve into whatever it is we need to be....in order to learn and survive in a weightless environment saturated with radiation.....

I cant understand why, when you hear of NASA's intentions, they always say "in about 20 years we will start building on the moon...or we will send a man to Mars..." why not just do it NOW ? they have obviously been thinking about it long enough.

Answer 5

Last week I read a Wikipedia article about Terraforming other planets. It had alot of theories on different ways to make other planets suitable for (Earth) life, as well as different planets/bodies that were good candidates. I was vaguely familiar with most of what the article had to say - but one thing blew my mind: Colonizing the Cloud-tops of Venus.

The clouds are made up of a 21:79 -Oxygen:Nitrogen ratio (basically what we breathe) which acts as a lifting agent in Venus' atmosphere. It also has 1 bar of pressure with temps. in the range of Earth temps...."an altitude of 50 kilometers above Venusian surface, the environment is the most Earth like in the solar system "

Answer 6

The moon first because it is close and easier to launch spacecraft from due to the lower gravity.

After that Mars would be the best bet, it has water making things a bit easier and other raw materials.

After that there is few planets in the solar system easy to colonise - possibly some of the moons of Jupiter

Answer 7

Assuming we could get their, if ever!. And assuming it was habitable.
I think a nice big planet like Neptune would do. Imagine having to conquer a World that huge. It might have made us primitive because species would be isolated from each other for so long. Or, we could have developed without knowing who was at the other side of the globe.
If any of these was the case, then I think we would be still in the early stone age compared with today. It would take twice as long to explore so would take mankind twice as long to evolve.
If we went today we would get there in 2 years.

Answer 8

With the demise of the sun, anything in our solar system would be fried. A "Battlestar Galatica" senerio would be our best option, many colony ships set up to survive many gererations until we reach a star system with a compatable planet.
Short of that, we need to look at the possibility of alternate universes and how to reach them. Maybe Earth isn't screwed up there.

Answer 9

They would have to find a planet that supported carbon life force's
as yet we haven't found any planets that would support us yet certainly for long periods without artificial means.
I think if the world was to be destroyed by a rock we would need to be advanced enough for infinite propulsion and be able to sleep in a cyrogenic chamber because in our physics boundary we have now it would take a thousand years to reach another galaxy that might have a similar planet.

Answer 10

Well the planet i would go to doesn't exist any more at least not in the form of a planet, but i think the asteroid belt would be a good choice for future colony's to live. The asteroid belt is close to mars and is full of mineral deposits ready to be mined.