Think of our poor sister world Venus – almost the same size as Earth, it probably had oceans at the beginning. But Venus was closer in to the sun — and was never in the continuously habitable Goldilocks zone. Instead our poor cousin Venus quickly got a greenhouse effect that erased its oceans, drove all the water away, leaving a desert world. And that’s what will happen to Earth – if we either fill the atmosphere with greenhouse gases – or if we just wait a hundred million years, as the Goldilocks zone inner edge moves past where our planet orbits.
So, let’s lift the Earth, raise it up – the whole planet! There are ways to do this – and reasons to do this. After all, anyone who saw Woody Allen’s movie Radio Days knows that we were promised five billion more years of having a habitable earth! It turns out that’s not true! Woody lied to us….It turns out that it’s five billion years until the sun, a G-type star, expands prodigiously and eats the earth. But a long time before that , the sun’s gradual increase in temperature is going to make our planet uninhabitable, perhaps as soon as one hundred million years from now – about the same timescale it took for mammals to evolve into us, after the asteroid killed the dinosaurs. Earth might have only one more chance if we blow it.
Earth skates the very inner edge of the so-called Goldilocks zone around our sun – the continuously habitable zone. This is the reason why only a little bit of carbon dioxide generated by human industry in our atmosphere is causing so many problems. Because we need an atmosphere that is almost completely transparent in order to lose heat fast enough. The Gaia balance adjusts the amount of greenhouse gas so that the seas stay liquid. If the earth had been where Mars is – and if Mars had been larger – we would have a sister world out there with oceans, and a very dense CO2 atmosphere – reached by its Gaia balance.
But we have no such wiggle room. We skate the very inner edge of our sun’s continuously habitable, or Goldilocks zone. And that inner edge is creeping outward slowly – don’t confuse this with human-generated climate change. This is much slower – but it’s too fast for comfort! In a hundred million years, the deserts will spread and the oceans will start to go away. We’ve got to get out of here! We’re told: You can’t move the earth, so flee! As Elon Musk wants to do, and so many others have talked about, we should create other habitable zones for humanity, both inside the solar system – Europa, Mars, the asteroid colonies – but also, interstellar.
But I have some emotional attachment to this planet. I’d like it to survive longer. So, can’t we do something for our Earth?
One method, if we were to get out into the solar system – we could steer asteroids. Those asteroids would swing right past the earth in near misses, and transfer some of their forward momentum to the earth with each pass, and gradually pump its orbit up. I think that’s one of the stupidest ideas ever imagined. Sure, it might work, if you were to fly past 10 million times. And in those ten million near brushes, what god-like level of competence would you require to know for sure that none of them would veer a little bit and strike the planet? Seems a bad idea.
Another possibility is called the Gravitational Tug. This is how we might move asteroids that are heading toward the earth, and shift them out of the way. That is to take a heavy spacecraft with an ion engine, and hover it near the asteroid and pump away with the ion engines, just enough so that the asteroid’s gravity is not broken away from. In that case the asteroid follows the spacecraft. We could set up an asteroid at the L1 or L2 or L5 Lagrangian points of Earth’s orbit and tug the earth away.
Now there’s a problem with these ideas. It’s going to take millions of years to lift something as heavy as the earth with little nudges. Generations. Eons. The lifespan of whole civilizations. Perhaps the lifespan of species. Moreover your method is going to have to survive rises and falls of these cultures. Periods of times when a society decides against investing in such projects, opting for short-term thinking. We don’t have the money right now, we’re passing through a depression. Perhaps civilization falls, and they have to recover and read the old records and re-realize the imperative that they owe their planet. Whatever method you come up with is going to have to survive disruptions, pauses, even changes of government.
Let’s pause and do an aside about Electrodynamic Tethers. I talk about them in my novel Existence, and in a short story, Tank Farm Dynamo. As the world expert on tethers, Joe Carroll has indicated, if you allow a conducting cable to settle into gravity as its orbiting around the earth, it will stable along a radius from the center of the earth. This is called Gravity Gradient Stabilization. Let’s say it’s made of a conductive material. This orbit is cutting through Earth’s magnetic field. So an EMF or electromotive force, or voltage, becomes induced – just like the armature of a generator – along the length of this tether. If you were to spew electrons off one end of the cathode, you would then be able to suck energy out of the orbit. The tether would slowly go down, but you’d get all the power you need for your space station. I talk about this in Tank Farm Dynamo.
But if you had a lot of power (with a nuclear power planet or solar cells) and push electrons against the EMF so that they spew out the other end. Now you no longer have the armature of a dynamo – but the armature of a motor! You’re cranking against the earth’s magnetic field, and the electrodynamic tether rises. The experiments have been done. Joe Carroll’s Tether Applications has done them with the Air Force. We’re about to use this method to send spacecraft around earth’s orbit without expending any rocket fuel – just energy.
Up with Space Elevators
You can see that this is a relative of the space elevator. The space elevator is a tether that is anchored to the earth at the equator and has a counterweight beyond geosynchronous orbit – with a big space station at geosynchronous orbit. The new carbon fibers may make space elevators a reality. Kim Stanley Robinson envisioned them around Mars in his novel, Red Mars. Let’s combine these concepts. Imagine a space elevator that is electrically conducting – cutting through the earth’s magnetic field. This will tug on the earth – and maybe tug it upward. There’s a problem. The earth is rotating so fast, with a 24 hour day, it would be very difficult to time the pumps in just the right way so that the effect is not on earth’s rotation but on its orbit. You have to add momentum to earth’s orbit, so that it rises – so that it gets farther from the sun.
There is another approach. You cannot count on generation after generation maintaining a space elevator on the earth. And if it falls, it’s going to do some damage. But, what if you put a space elevator on the other side of the moon? If it falls, not a lot of damage. If it breaks, the elevator just floats away into space. If this space elevator on the moon were also electrically conducting, it would take commerce in, receiving resources from the asteroids. It would be sending out refined, developed materials, part of a lunar industry. People would be counting on this space elevator, without thinking about what it going on in the background. That is: you have a conducting cable that is cutting through the sun’s magnetic field. Now it takes a month for the orbit so it’s easier to time the pumping of the electrons. A constant rhythmic pumping action that is tugging on the moon. As it tugs on the moon, the moon tries to rise, but the earth resists – and the earth follows!
This is how you raise the planet, without endangering the earth with asteroid flybys. You pump it with an electrically conductive space elevator on the far side of the moon. The great advantage? Civilizations can rise and fall. Budgets can be cut. The tether can be cut; it just floats away. You replace it. Over the course of millions of years, all you need is for phases of the rich civilizations to do this – maybe half the time – and move the planet. As the sun’s heat moves the continuously habitable zone, or Goldilocks zone, further outward.
The question is, could this solve our problems now, with global climate change? There’s a branch of science called geoengineering. Too many people are opposed to even thinking about it. There’s nothing wrong with doing preliminary experiments. Of course our number one job is to prevent things that we are doing that are harming the earth.
Indeed, most of the actions required to prevent Global Climate Change are TWODA – Things We Ought To Do Anyway. Actions that would help us to become more energy-efficient, and save money, while alleviating the rise in earth’s greenhouse gases. We should be able to talk about options to find win-win engineering projects that could help us save the planet. Stirring bottom muck in the oceans could raise so much plankton that we stimulate new fish nurseries, like what happens off the Grand Banks of Newfoundland, or in Chile. That might suck carbon out of the atmosphere. But…should we be thinking about moving the earth a little farther away from the sun? I think that’s a little too ambitious — for now. But it’s not too soon to be thinking – in science fictional terms – about the ambitions that our rich and fantastically capable descendants might undertake to save this planet that’s been very good to us.
Lift the Earth!