Since Mercury is the closest planet to the Sun, followed by Venus, Earth, Mars, etc..., we’ve always believed that Venus was our closest planetary neighbor, but new research suggests that we may be wrong.
According to a commentary published in the magazine Physics Today, while Venus does come closest to Earth when it passes by, Mercury is the planet the stays the closest to us for the longest amount of time.
Tom Stockman (Ph.D. student at the University of Alabama), Gabriel Monroe (mechanical engineer at the U.S. Army’s Engineer Research and Development Center), and Samuel Cordner (mechanical engineer at NASA), wrote in the commentary, “By some phenomenon of carelessness, ambiguity, or groupthink, science popularizers have disseminated information based on a flawed assumption about the average distance between planets.”
When calculating the distance between two planets, it is normally determined by measuring each of their distances from the sun; however, that only determines the distance from the two planets when they are closest to one another. Since the two planets move at very different speeds, Venus is sometimes on the opposite side of the Sun and quite far away from Earth.
Researchers figured out the distance between planets by using a new mathematical technique called the point-circle method in which they calculated quite a few different points on each planet’s orbit. In addition, they were able to map out where the planets were situated every 24 hours during a 10,000 year period. By using that new technique, they determined that Mercury stayed the closest to Earth for the longest amount of time. What’s even more interesting is that Mercury is also the closest to all the other planets in our solar system.
Unfortunately for the researchers involved with this new theory, not everyone is on board with their idea. Steven Beckwith, who is the director of the Space Science Laboratory and professor of astronomy at UC Berkeley, disagreed by saying, “Suppose you live in a house where the people who live next door to you spend half the year someplace, maybe you live in Wisconsin and your nearest neighbors spend seven months of the long winters in Florida. During the winter, the people in the next house over would be closer to you.” He went on with his example by stating, “But most people would still say that their closest neighbors are the ones who live immediately next door for the rest of the year. It is an interesting way of redefining ‘closest’, but it is hardly profound.”
With Venus being our nearest planetary neighbor when it orbits by us, but Mercury staying the closest to us for the longest amount of time, whatever your definition of “closest” is, it is nevertheless a very interesting theory to ponder.