Dr. Matthew J. Genge is a researcher at the Department of Mineralogy at the Natural History Museum in London, where he studies meteorites, cosmic dust and planetary defense. This article, written in response to the idea that Earth could be moved to a higher orbit to protect it against a warming Sun, first appeared Feb. 8 in a scholarly newsletter called CCNet. It has been republished here with permission.

Don Korycansky, Gregory Laughlin and Fred Adams have suggested that the Earth's orbit could be changed in order to moderate the Earth's climate. The technique is relatively simple and, rather worryingly, perfectly possible using modern day technology. Just change the orbit of a large asteroid so that it comes close enough to the Earth to change our planet's angular momentum. This technique is nothing new, in fact it was responsible for the migration of the planets four and a half billion years ago whilst they cleared the solar system of left over planetesimals. Korycansky, Laughlin and Adams rather sensibly acknowledge that this would be a delicate operation since aiming a huge rock at the Earth does have one or two minor risks associated with it. The extinction of 75 percent of species on the planet being one of them. Rather a hefty price to pay for clement weather.

Using long term propulsion techniques such as mass drivers or solar sails the change in the orbit of an asteroid could be achieved very reliably and, secular perturbations allowing, the idea would work. There would be some small things to check first. Changing the Earth's orbit would change its perturbation of the orbits of the other planets, asteroids and comets and you would certainly not want to move directly into the path of an impactor. It is perhaps this 'safety first' task that is beyond our current knowledge.

There is, of course, no need to move our planet's position in the solar system. It would be folly indeed to try and compensate for a short-term climatic disturbance such as global warming even if we could reliably predict how our planet's climate would change after the move. Only in 4.5 billion years or so when our Sun starts to become a red giant will the inhabitants of the Earth perhaps have to think about taking such drastic action. It would, in any case, be politically rather difficult for any government to unilaterally decide to move the global vegetable patch to a sunnier part of the cosmic garden. The chances of all world governments agreeing on any course of action being very slim indeed.

Perhaps the most interesting implication of this suggestion is what it means for the human race as a whole. The Russian astronomer Nikolai Kardashev suggested that civilizations could be classified into four groups of which ours is a type 0 civilization, struggling for survival on a single planet that we can't control. The knowledge and the ability to modify the configuration of a planetary system to create a more hospitable and efficient environment is one of the criteria for a type II civilization. Shifting planets around in a game of cosmic billiards being an ingenious alternative to the construction of a Dyson sphere. We now have the knowledge and the ability; all we lack is the impetus. In short it appears the human race has just been promoted.

Click here to read the news article: Recipe for Saving Earth: Move It