The mass of Mercury is 0.33x1024kg, while the mass of the Earth is 5.97x1024kg. As a result, Mercury has a lower mass than the earth (or, in other words, the earth's mass is approximately 18 times bigger than Mercury's).
Alternatively, you can look at it this way: The average density of Mercury is 1180kg/m3, while the average density of the Earth is 3140kg/m3. This means that mercury has about 18% of the density of earth.
As for its size, it averages 63 miles in diameter, but some parts are as small as 15 miles or more across. The reason for these huge differences in size are actually quite simple: Like the moon, Mercury was once a giant planet that lost most of its atmosphere and collapsed under its own weight. Today, it is only half as thick as Earth's atmosphere would have been, which explains why it looks like a bright ball from space.
Interestingly, even though it is so much less massive and less dense, the Earth still pulls slightly on Mercury because they were part of the same original lump of matter.
Mercury is a naturally occurring component of the earth's crust, with an average abundance of roughly 0.05 mg/kg and large local variations. The most significant source of human-induced mercury pollution is the atmosphere, where it enters the environment through volcanic eruptions and other mechanisms. Most research indicates that this form of mercury does not remain in the environment long enough to be absorbed by plants or animals, but it can be transformed by microbes into more bioavailable forms that may have toxic effects for living organisms.
On Earth today there are about 375 tons of mercury, of which 300 tons are in the form of elemental mercury. The remaining 75 tons are organic mercury, which is bound to carbon and other substances. Organic mercury is also known as "vital" or "bioavailable" mercury because it can be taken up by living things from the environment.
The global annual production rate of elemental mercury is approximately 2 million tonnes, while that of organic mercury is between 4 and 5 million tonnes. The main natural sources of elemental mercury are volcanoes, while sedimentary rocks contain most of the organic mercury.
Human activities such as gold mining, coal burning, and industrial emissions contribute additional amounts of mercury to the environment. Annual human production of mercury reaches 15 million tonnes, almost all of it removed from ore deposits.
Mercury is one-third the size of the Earth, with a diameter of around 3,100 miles. Mercury's look is similar to that of our own moon in many aspects. So, how much weight does mercury have? It is the second most dense planet in our solar system, weighing 330 trillion tons. That makes it about 98% water.
Its mass is equivalent to about 8,800 times the mass of the Earth. This makes it by far the least massive planet outside of Earth's orbit.
Even though it is so small, Mercury has been found to have a large iron core surrounded by a metallic mantle and crust. Like the other planets, Mercury went through an early phase of nuclear fusion before its core formed. The heat from this process was enough to melt the outer layers of Mercury, forming a magma ocean for several hundred million years. As the planet cooled down, its core formed from these metals.
The average density of Mercury is 4,448 kg/m3 which is very close to that of iron. Because such a small planet has a large amount of iron inside its radius, it must be compressed extremely tightly. This means that Mercury is extremely rigid and not flexible like a human being for example.
It takes Mercury only 58 days to complete one rotation because it is completely covered by clouds most of the time.
Mercury has the smallest and least massive planet in the solar system due to gravity. Mercury, on the other hand, has a surface gravity of 3.7 m/s2, which is the equivalent of 0.38 g due to its high density—a robust 5.427 g/cm3, which is just slightly lower than Earth's 5.514 g/cm3. That makes it difficult for humans to live on Mercury because the pressure from having over half of your mass as gravity is crushing you down.
The strength of mercury's gravitational field has been measured using two different methods: by observing the perihelion advance of Mercury's orbit or by measuring the deflection of starlight by the planet's shadow. The former method yields a value between 44 and 58 mm/year, while the latter yields a value between 75 and 95 mm/year. These results agree within their uncertainties.
Both methods show that the strength of Mercury's gravitational field is greater than that of Earth but less than Saturn's. However, since Mercury has only 5% of Earth's mass, its gravity is 100 times weaker than Earth's.
People have tried to live on Mercury before. In 1978, the Mariner 10 spacecraft discovered evidence of large amounts of water ice under its surface. In 2011, scientists reported finding carbon dioxide ice in the same region of Mercury.
This means that if people were to colonize Mercury, they would need to bring everything with them when they go, including air, water, and food.
Mercury is the solar system's smallest terrestrial planet, measuring around one-third the size of Earth. It has a thin atmosphere, which allows temperatures to fluctuate between scorching and freezing. Mercury, like Earth, is a dense planet made largely of iron and nickel, with an iron core. However it is not as well protected by ice caps or oceans because most of its surface is exposed to the sun's heat.
Like the other planets, Mercury orbits the Sun once per revolution around its axis every 58 days. But because of its small mass, almost all of the planet's gravity comes from the Sun, so its orbit is very close to being a straight line. This means that any air currents or weather patterns on Mercury are likely to be extremely localized, since they can't persist for long periods of time.
The main reason scientists think Mercury might have had water on its surface in the past is that it used to be much more earthlike, about 4.5 billion years ago. At that time, our planet was still warming up from its formation process, so there was probably liquid water under more moderate conditions than today. Also, at those times there were no large bodies of water anywhere in the Solar System, so any water that did exist would have been isolated on Mercury.
Mercury is closer to Earth on average due to its closer orbit around the Sun. The average distance between Earth and Mercury is about 363,000 miles (590,000 km). Because Mercury has no magnetic field, all the iron inside it is hot. This is why it looks like a big ball of fire as it orbits behind Earth every 88 days.
Earth's moon has a similar size and mass to Earth but it orbits much farther away from us at about 240,000 miles (390,000 km). The reason we have two different kinds of bodies with such similar characteristics is because they formed from the same cloud of gas and dust about 500 million years ago. Jupiter, which is more than 100 times as massive as Earth, joined together with Saturn to form what was once a large planet called Uranus. Neptune, which is more than 10 times as massive as Earth, zipped in next to fill out the solar system.
All the planets in our solar system are classified as terrestrial planets because they consist mainly of iron and nickel. The other planets are mostly empty space with a few small rocks floating around in them.