Reveals that mercury could actually be the closest planet to Earth

We often think that Venus is our closest brother to the solar system. It is the most similar to the Earth in size, mass and composition. And we thought it was the closest physical distance, but it seems that this honor could belong to Mercury.

No, the order of the planetary orbits is always the same. Mercury is still the innermost planet and the orbit of Venus is always the closest to Earth's orbit. But, according to new calculations, Mercury is on average closer to Earth than our old BFF.

This seems counterintuitive, is not it? And that is perhaps what led us to the wrong idea in the first place

"By a phenomenon of carelessness, ambiguity or group thinking, scientific popularizers have disseminated information based on a mistaken assumption about the average distance between planets," write the engineers Tom Stockman, Gabriel Monroe and Samuel Cordner in a commentary published in Physics today.

"Using a more accurate method to estimate the average distance between two bodies in orbit, we find that this distance is proportional to the relative radius of the internal orbit.

"In other words, Mercury is closer to the Earth on average than Venus because it turns more around the Sun."

The team, whose workplaces cover the Los Alamos National Observatory, the US Army Engineering Research and Development Center and NASA, has not yet published its calculations in an article reviewed by peers.

The team notes that the way we usually calculate distances between planets is based on their distance from the Sun. The Earth, on average, is an astronomical unit (AU) of the Sun. Venus is 0.722 AU. The mercury is 0.387 AU.

But if you subtract the distance from Venus to that of the Earth, you actually get the average distance between their orbits – not the distance between the planets themselves. As the planets move at different speeds, they spend a lot of time on both sides of the sun.

Because Mercury is closer to the Sun, the distance between it and the Earth when they are at their furthest distance is much smaller than the distance between Earth and Venus.

The team developed the "point circle method" or PCM equation to calculate the average distance between two planets in concentric, coplanar circular orbits (on the same orbital plane).

(Stockman et al., Physics Today, 2019)

According to their results, it's not just the Earth. Mercury is actually, on average, the closest planet to all the other planets. Yes, even Neptune, in the margins of the solar system. And yes, even the distant dwarf planet Pluto (although its highly elliptical orbit complicates the calculations).

The team named their discovery … Whirly Dirly Corollary: "For two bodies with roughly coplanar and concentric circular orbits, the average distance between the two bodies decreases as the radius of the internal orbit decreases. . "

To test it, they created and executed a simulation mapping the positions of all planets in the solar system over a 10,000-year period and compared the results with traditional distance measurements and PCM results. The simulation only varied by 1% with PCM – but up to 300% with traditional distances. Yuck.

"At best, nobody has developed a concept such as PCM to compare orbits," the engineers write.

"With the right assumptions, PCM could eventually be used to get a quick estimate of the average distance between any set of bodies in orbit." May be useful for the quick estimation of satellite communication relays, for which the force signal decreases with the square of the distance.

"In any case, at least we now know that Venus is not our nearest neighbor – and that Mercury belongs to everyone."

You can never have too many planet pals, though. We are all for the enthronement of Mercury in the club of the best friends on the planet, rather than chasing Venus. We still love all our neighbors, near and far. Even you, distant dwarf planet, Pluto.