Imagine a planet without seasons. There his two years pass in her three days, and the light does not reach the pole. The surface temperature is high enough to melt lead and low enough to freeze methane. But most of all, as if someone had pressed the rewind button, how it feels to contemplate a sunset as the sun dips below the horizon, recedes a moment later, and disappears into the western twilight a day or two later. Imagine what it is.
That strange planet is right next door and is called Mercury. Mercury moves around the Sun faster than any other body in the solar system, completing one revolution every 88 days. Although it is very bright in the sky, its closeness to the Sun makes it very difficult to study and we don’t know much about it.
Because it moves quickly through the sky and is small, this planet was associated in ancient Greece with its role as an intermediary, bringing one god into contact with another. Mercury’s name comes from the Roman god of shopkeepers, merchants, thieves and tricksters. It is related to the Egyptian god Thoth and the Norse god Odin, and it also held an important position as a celestial body in Mayan culture. The relevance of this myth in different cultures all highlights something very simple. That is, it is a conspicuous object in the night sky.
The planet rotates very slowly, which is why the days and nights are so long. Her day on Mercury is equivalent to 58.6 days on Earth. Since it is the closest planet to the sun, its year is extremely short, with only 88 Earth days. As in the case of the Moon, its rotation period is not synchronized with its orbital period, but in what is known as a 3:2 resonant orbit, both periods are similar. This means that with each revolution around the Sun, or orbital period, Mercury makes one and a half revolutions around its axis. And in her two complete orbits around the sun, the planet rotates around her axis three times. Although one side of the planet does not always face the sun and the other side is in complete darkness, there are very long periods of alternating darkness and light.
Mercury moves in a fairly elongated orbit around the Sun, averaging a distance of 57.9 million kilometers. According to Kepler’s second law, in such an elliptical orbit, the speed of the planet changes significantly at its most extreme points. Therefore, when Mercury is at perihelion (the point of its orbit closest to the Sun), it moves at a speed of 59 kilometers per second (remember that Earth moves at 30 kilometers per second). Recall that the measurement of Mercury’s perihelion advance, explained in terms of space-time curvature, was one of the key elements used to prove general relativity.
On the surface of Mercury, the sun rises in the east and sets in the west, just like on Earth. But once a year, when it passes perihelion, its orbital motion outstrips the planet’s slow rotation, blocking the sun’s path for that day. It is at that point in its orbit that you can watch the strange sunset. The star comes to a complete stop in Mercury’s sky and retreats to return to its normal orbit as the planet slows and moves through its orbit.
Because Mercury is closer to the Sun, the light reaching its surface is seven times more intense than Earth’s. And that light takes about three months to heat the surface. The planet rotates so slowly that its surface temperature is hot enough (more than 420 degrees Celsius) to melt lead. Similarly, the time it takes for the sun to set and rise again is about three Earth months. For three months in total darkness, it would cool the Earth’s surface to nighttime temperatures below -170 degrees Celsius, cold enough to freeze methane and carbon dioxide.
Mercury has no seasons because it rotates about an axis nearly perpendicular to its orbit. This also means that in polar regions the interior of large craters is permanently in shadow. One of the big mysteries is bepicolombo The spacecraft is trying to determine whether these craters contain sulfur or ice.
small planet Mercury has a magnetic field similar to ours, but only 1% as strong, making it unique among the solar system’s rocky planets because it has a self-sustaining magnetic field similar to Earth’s. We still don’t know why Earth and Mercury maintain magnetic fields, but Venus, Mars, and the Moon do not.
Mercury still remains a mystery, and a joint mission between the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) is playing a role in solving it. bepicolombo I’m trying to solve it. She has only been visited twice. Mariner 10 and messenger probe.
BepiColombo will be the third probe of this unique, small, mysterious and difficult-to-explore planet that has helped lay the foundations of modern physics, and will provide fundamental insights into the evolutionary history of the solar system and its formation. It will definitely give you a clue. Earth.
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