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Armageddon for the solar system may happen sooner than originally thought

The solar system, showing the Sun and planets.
Credit: Via Wikipedia
Attribution: CC BY-SA 3.0
Our solar system will disintegrate much sooner than scientists originally thought. Or at least that's what a couple of astronomers at the University of California think.

The prevailing opinion was that it would take a billion billion (a quintillion) years for the solar system to fall apart, but this new paper suggests it will only take 100 billion years. So remember to cancel the papers.

We'll be long gone before that. In about 5 billion years the Sun will swell up to become a red giant and it will engulf Mercury, Venus and Earth in the process. That's when the lights will go out for us. However, the outer planets will survive. The Sun will then eject a load of its mass and shrink down to become a white dwarf. This white dwarf will be about half the mass of our current Sun and it will thus have less gravitational control over the remaining planets.

We rotate around the galactic core and this brings us nearer to other star systems at times. The Sun's lesser gravitational attraction renders the remaining planets susceptible to influence from stars that come close enough. Without so much as a by-your-leave, these other stars will drag the remaining planets off on to a path of their own through the galaxy.

This is all tricky to work out because it's an n-body problem. It's easy enough to solve where n = 2 and they can make a fist of things where n = 3, but as more bodies are added to the system in question they have to make simplifications in order to carry out the calculations. Think of it like this: body 1 is linked to body 2 by gravity and then introduce body 3. Body 3 affects bodies 1 and 2, and then the subsequent effect on body 2 changes the way that affects bodies 1 and 3, and so on. You have a constant feedback loop with bodies affecting one another in an evolving system, which is similar to what tends to happen in a nightclub if you think about it.

Newton understood the complexities of n-body problems and said they gave him a headache.

What you need to model this sort of thing is a computer, and the more powerful it is the fewer simplifications you need to make and the more bodies you can add. Nevertheless, predictions made this way or inherently dubious.

You can model an entire galaxy quite nicely by making many assumptions and using statistics. This is how they might produce something like this:

But modelling specifics — such as what will happen to Jupiter — is far harder. The authors of the paper note that their conclusions are contingent upon many assumptions based on current observations.

There's good science and mathematics involved here, so it's not like standing on a street corner and shouting "the end is nigh," but it's still an educated guess that this will all happen in 100 billion years. The takeaway is that it's likely the solar system will be totally dismantled considerably sooner than scientists originally thought.

I've noted it in my diary and I'll raise a glass to the solar system from my beach home on a planet orbiting Betelgeuse.