Image: Applied Physics Laboratory at Johns Hopkins University / Carnegie Institute in Washington (Wikimedia Commons), not Venus, is the closest planet to Earth on average.
Researchers presented their results this week in an article in the journal Physics Today. They explain that our methods of calculating which planet is "the closest" simplifies the matter. But that's not all. "Besides, Mercury is the closest neighbor, on average on each of the other seven planets in the solar system," they write.
Our misconceptions about the proximity of the planets to each other come from the way we usually estimate distances to other planets. We usually calculate the average distance from the planet to the Sun. The average distance of the Earth is 1 astronomical unit (AU), while Venus is about 0.72 AU. If you take one of the other, you will calculate the average distance from Earth to Venus as 0.28 AU, the smallest distance for each pair of planets.
But three researchers realized this was not an accurate way to calculate distances to planets. After all, Earth spends just as much time on the opposite side of its orbit from Venus, placing it at 1.72 AU. Instead, the average distance between each point in orbit of a planet and every point in the orbit of the other planet should be calculated. Researchers conducted a simulation based on two assumptions: that the orbits of the planets are approximately round and that their orbits are not at an angle to each other.
In a sense, it makes sense – if you get places for a football match, you prefer a person close to the 50 yards line instead of one of the end zones to see the most action, even if you are sometimes closer to the players in the end zone. This is something that happens here.
Indeed, they found that Mercury is the planet that is closest to Earth at most, on average – on any other planet of the Solar System. Pluto's inclined and eccentric orbit does not work with their assumptions, but it is not a planet as defined by the International Astronomical Union. Please do not write me about this.
You can read about the Mathematical Thread in Physics Today or watch an explanation of math on YouTube.
But in the absence of obvious errors in the analysis, I think it's time to say "bye!" At Venus and meet our newest neighbor, the best planet, Mercury.