Being a well-read bunch I’m sure everyone here has come across the ‘grey goo’ scenario where an outbreak of rogue self-replicating nanomachines turns the entire mass of planet Earth into copies of itself in a few days/hours.
However instead of functioning at such a rapid rate what if the the grey-goo was converting the surface of the Earth at a much slower rate, say the circumference of the grey-goo area was expanding at a rate of circa 10 miles per day, from the unfortunate research centre where the experiment went wrong, slowly dissolving and converting all matter it comes into contact with (for reasons of plot assume that the nanomachines are broken down by contact with hot magma, so it affects the earths crust only).
Also for the scenario humanity doesn’t/can’t come up with a means of reversing or slowing the process, the surface of the Earth is going to be converted.
I actually intended to mention that by the time everyone wakes up enough to the threat thats not a viable option (it has expanded too far and even a bit surviving, by being blown into the atmosphere to land elsewhere is enough to start the whole process again)
Well…when it eats the crust down to magma that magma is going to spew out. Ten miles per day? Sounds like we have a ten mile wide volcano and the next threat is nuclear winter.
Edit: But to stay in the spirit of your thread…we all die? A lot of people kill themselves…some societies fall apart, some keep a stiff upper lip. There’s a lot of sex?
Some sci-fi fans might remember “The Leech” by Robert Sheckley. At the risk of a minor spoiler, they sucker the effect into space by dangling really yummy bait (high-energy radioactives) above it, and it levitates up to try to nom it.
So… If the thing is reacting to stimuli, we might be able to guide it into some sort of trap.
Otherwise, in the scenario you describe… It’s like those moral quandaries, “The world is going to end in two months: what do you do?”
Increasing in circumference at 10 miles per day is going to be slow indeed, on the order of several years right? Earth’s surface area is 198,000,000 sq miles, and a circumference increase of 10 miles per day only increases the diameter of the affected zone by about 3 miles per day – that’s a pretty slow creep.
Can somebody who’s not an English major do the math?
The Earth’s circumference is 24,900 miles. That means that the distance from the starting point to the point where it will meet on the opposite side of the earth is 12,450 miles. So it the spread is advancing at 3 miles a day, it will take 4,150 days (about eleven years and four months) to complete its destruction.
eta: My mistake. It’s the diameter that’s increasing at three miles a day not the radius. So double the time it would take to reach the end point: twenty-two years and eight months.
