- Astronomers argue in the journal Physics Todaythat Venus or Mars are not closest to Earth – but Mercury.
- This is true if you do not look at the shortest distance, but at the average distance from Earth.
- Mercury is the sunniest planet. Nevertheless, according to the new definition for all planets in the solar system, he would be the nearest neighbor.
Which is the nearest Earth planet? Most people will touch one of these two celestial bodies: Venus or Mars. The earth eventually circles on its orbit around the sun between the elliptical orbits of these two planets. Venus circulates a little closer to the sun, Mars farther away. Alternatively, with a lexicon or two mouse clicks can be quickly clear who comes closest to the earth: It is the Venus.
But now astronomers calculate in the magazine Physics Today that you should see things differently. The question of the nearest planet depends on the definition of "closeness": is it actually the planet that is closest to the earth? The astronomers argue: Actually, it should go to the planet whose mean distance to earth is the shortest. So the planet that we humans would have to interpret most days when it comes to which planet is just next. Seen in this light, the answer is astonishing: the planet closest to Earth is Mercury. Yes, Mercury, that obscure dwarf that revolves around our central star in the solar system, so close that lead would melt on it, and the sun's gravity almost rips it apart.
Venus is more often on the other side of the sun
Can this be? Well, it reminds a bit of the question about the highest mountain in the world. Of course, Mount Everest, many will say. But here, too, everything depends on how to define "height". Everest, measured from sea level, is the highest elevation in the world. If one considers the height difference between foot and peak, no matter whether the foot is under water, the 10 200 meter high flank of Mauna Kea on Hawaii surpasses the colossus in the Himalayas. And if one defines height as the distance of the summit from the center of the earth, suddenly the top of the Chimborazo in Ecuador is the record holder. The latter is because the earth is not a sphere, but thicker because of its rotation around the equator than at higher latitudes.
For our planetary system, the astronomers have now calculated that Mars as well as Venus and all other planets most of the time are further away from Earth than Mercury. Its average distance to us is about the distance to the sun, about 150 million kilometers. Although Venus occasionally approaches Earth at 42 million kilometers, it is more often on the other side of the sun. Their average distance to us is an impressive 170 million kilometers, which is more than the average distance to Mercury. The same applies to Mars.
Not to treat it theoretically, astronomers have had a computer chew through the actual positions of all planets over the past 10,000 years. It was confirmed that Mercury is not only the closest planet on Earth, but is also closest to all other planets in the Solar System, including Neptune. So let's welcome him, Mercury, the so far overlooked but basically the most loyal and closest neighbor on Earth.