The Earth has treasures of all kinds and is the lonely planet that has life. There are planets that are full of diamonds and mysterious clouds. Nevertheless, we love our “pale blue dot” that stands out because of its ability to sustain life. Here are some interesting earth facts.
What Earth is composed of
Earth, is the third planet on the Solar System. It is also the only one known to date having liquid oceans on the surface and above all, it is the only one to support life as we know it. It is also one of the four rocky/ telluric planets of our system among which you will find Mercury, Venus and Mars. These rocky planets are mainly composed of solid rocks and metals and their material has a high density which leads to a slower rotation. Also, they have no rings and only a few satellites.
The imperfect sphere
The Earth is not a perfect sphere. Earth should be a perfect sphere. Except that the Earth is not motionless, it turns and therefore the centrifugal force generated by this movement is maximum at the equator and zero at the poles. Result: the Earth is “stretched” and is wider at the equator. Finally, the surface of the Earth is not totally smooth. Peaks over 8000 m with Everest as well as depths of upto 11,000 meter in the Mariana Trench are present on the Earth. At the equator, the circumference of the globe is 40,075 kilometers.
Revolution Speed: The Earth rotates at an almost constant speed and completes a revolution in about 23 hours, 56 minutes and 4.1 seconds. At the equator, this equates to an average speed of 1670 km / h around the center of the Earth.
Rotation Speed: The Earth is also in orbit around the sun, moving at 107 280 km / h. And the Sun itself revolves around the Milky Way at speed of 700 000 km / h!
Elements, metals and minerals
Our planet is surrounded by about 38,000 pieces of space junk, which include small objects to deactivated satellites.
99% of the planet’s gold is located at its core. This amount is enough to form a 50 centimeter crust around the planet.
The center of the Earth is formed by a solid sphere of iron and nickel. The temperature is almost 5,000 degrees Celsius and the pressure is higher than the temperature, which prevents the molecules from shaking.
Too hot to penetrate
Because of the high temperatures, no human probe could reach the center of the Earth. To know what exists in the center of the planet scientists use calculations and rely on sophisticated studies. Among them, the analysis of the composition of meteorites, the relation between the density of the Earth and the rocks of its surface is also considered.
Meteorites from Mars in Antarctica
Chemical analysis of meteorites found in Antarctica, the Sahara Desert and elsewhere show that they originate from Mars, containing compositions chemically identical to the Martian atmosphere.
These meteorites may have been expelled from Mars due to an impact of meteors or asteroids on the planet, or a massive volcanic eruption, later colliding with Earth.
Must know facts
- The time it takes for the Sun to appear in the same meridian in the sky is known as the solar day.
- The time it takes for a distant star to appear in the same meridian in the sky is known as the sidereal day.
- In the perihelion, which is the nearest point, we are 147,095,000 km from the Sun, while in the aphelion, the farthest point, is 152,100,000 km.
- The Earth does not revolve around the Sun in a perfect circle. This phenomenon is known as Kepler’s First Law, which states that “the orbit of a planet around the Sun is an ellipse, with the center of mass of the Sun in the middle.”
- This Earth orbit lasts approximately 365.2 days, and it is for this reason that every four years it takes an extra day: the February 29 that we have every leap year.
- The Earth’s orbital velocity increases when it is closest to the Sun. Its average velocity is about 29.8 km / s, but it varies 1 km / s during the course of the year.
- Precession is the change in the direction of the axis of a rotating object. The Earth rotates (precesses) just as a spinning top does. The earth’s period of precession is about 26,000 years. This movement has no effect on the seasons, but makes visible stars in the sky change position at different times of the year.
- As the Earth revolves around the Sun, the combined gravitational pull of other planets varies over time, causing small oscillations in the Earth’s orbiting position.
Did you find facts about earth interesting? Check out some facts about exoplanets.