Solar system’s future could be bumpy
Study calculates the odds that two planets collide or one crashes into sun in the next 5 billion years
By Sid Perkins
It’s happened before, and it could happen again: Planets in the inner solar system may collide if gravitational interactions substantially disturb now-stable orbits, a new study suggests.
Scientists and mathematicians have long known that the equations describing the orbital motions of any group of three or more objects can’t be solved exactly. Even with the most powerful computers, it is hopeless to try to determine precisely what planetary orbits will look like more than a few million years in the future, says Jacques Laskar of the Paris Observatory. The results of any single simulation offer nothing more than one possible outcome, but running a large number of simulations can provide insights into overall probabilities, he notes.
Now, a large-scale study by Laskar and observatory colleague Mickael Gastineau, which appears in the June 11 Nature, provides a possibly frightening glimpse into the solar system’s future. It’s a future in which, literally, worlds collide.