Mercury, not Venus, is the closest planet to Earth

A team of scientists has just demonstrated something that might shock you: Mercury, and not Venus, is the planet closest to the Earth on average.

The researchers presented their findings this week in an article in Physics Today magazine. They explain that our calculation methods for the "nearest" planet make the question extremely simple. But that's not all.

"Furthermore, Mercury is the closest neighbor, on average, to each of the seven other planets in the solar system," they write. Wait what?

Our misconceptions about planetary proximity come from the way we usually estimate distances to other planets. Normally, we calculate the average distance from the planet to the sun. The average distance of the Earth is 1 astronomical unit (AU), while that of Venus is about 0.72 AU. If you subtract one from the other, you calculate the average distance from Earth to Venus equal to 0.28 AU, the smallest distance of all pairs of planets.

But three researchers realized that it was not a precise way of calculating distances to the planets. After all, the Earth spends just as much time on the other side of its orbit as Venus, which puts it at 1.72 AU. Instead, we must calculate the average distance between each point in the orbit of one planet and each point in the orbit of the other planet. The researchers performed a simulation based on two assumptions: the orbits of the planets were approximately circular and their orbits were not inclined relative to each other.

That makes sense: if you wanted to sit down for a football game, you'd prefer a match near the 50-meter line rather than one of the goal areas to see the maximum number of actions, even if you're sometimes a lot closer. to the players in the end zone. It's a bit like what's going on here.

Indeed, they discovered that Mercury was the planet closest to Earth for the longest, on average, and all the other planets in the solar system. The inclined and eccentric orbit of Pluto does not work with their assumptions, but it is not a planet anyway, as defined by the International Astronomical Union. Please do not send me mail on this subject.

You can read articles on Physics Today or watch a Mathematics Explainer on YouTube.

But if there is no blatant error in the analysis, I think it's time to say "goodbye!" To Venus and welcome our new closest neighbor, the best planet, Mercury.