Seen from our personal point of view, our planet seems static because it does not move with respect to ourself. But in reality, Earth is in perpetual movement around the Sun and more. Once you know how fast Earth moves around the Sun, you will be curious to also learn what causes this speed and how. Let’s answer to the question first: Earth moves around the Sun at an average speed of about 29.78 kilometers per second, or about 67,000 miles per hour. This movement, known as orbit, is caused by the gravitational pull of the Sun on Earth.
Earth’s orbit is not a perfect circle, but rather an ellipse with the Sun at one of the two foci. This means that the distance between Earth and the Sun varies throughout the year. At its closest point, known as perihelion, Earth is about 147 million kilometers (91 million miles) from the Sun. At its farthest point, known as aphelion, Earth is about 152 million kilometers (94 million miles) from the Sun.
The time it takes for Earth to complete one orbit around the Sun is known as a year. On average, a year on Earth is 365.24 days long. However, this length can vary due to the elliptical shape of Earth’s orbit, as well as the gravitational pull of other planets in the Solar System. When you know the distance that Earth takes around the Sun and the time, then divide the distance by the time and you will find how fast Earth moves around the Sun. Easy? Not so fast.
Earth’s orbit is also tilted at an angle of about 23.5 degrees relative to the plane of the Solar System, known as the ecliptic. This tilt is responsible for the changing seasons on Earth, as the tilt causes different parts of the planet to receive different amounts of sunlight throughout the year.
Earth’s orbit is also not static. Over time, the position of the planet in its orbit changes due to the gravitational pull of other planets and the effects of the Sun’s gravity on the planet. This is known as precession, and it causes the position of the Earth in its orbit to change by about 50.3 arcseconds per year.
Is the Earth’s speed fast or slow?
The speed at which Earth moves around the Sun is incredibly fast, but it is still much slower than some other common speeds. For example:
- The speed of a commercial jet, such as a Boeing 747, is about 926 kilometers per hour (about 575 miles per hour). This is about 115 times slower than Earth’s movement around the Sun.
- The speed of sound in air is about 343 meters per second, or about 767 miles per hour. This is about 86 times slower than Earth’s movement around the Sun.
- The speed of light is about 299,792,458 meters per second, or about 671 million miles per hour. This is about 10,000 times faster than Earth’s movement around the Sun.
It’s important to note that these are approximate speeds and can vary depending on the medium (such as sound in air vs sound in water) and altitude.
It’s also worth mentioning that while the speed of Earth’s movement around the sun is relatively slow compared to other speeds in the universe, it’s still incredibly fast in relative terms. It allows us to travel around the sun in 365.24 days and experience the changing of seasons. Additionally, this speed is crucial for the survival of life on Earth as it allows us to be in the habitable zone, where the temperature is just right for liquid water to exist and for life to thrive.
What are the factors affecting Earth’s speed
Everyone knows that the Sun’s gravitational force is the main source of Earth’s speed, but what are the other sources?
There are several factors that can affect Earth’s speed as it orbits the Sun:
- Gravitational pull of other planets: The gravity of other planets in the Solar System, such as Jupiter and Saturn, can affect Earth’s orbit by altering its speed and path. This is known as planetary perturbation.
- Solar activity: The Sun’s gravity plays a major role in keeping Earth in its orbit. However, changes in the Sun’s activity, such as solar flares and coronal mass ejections, can also have an impact on Earth’s orbit by altering the amount of energy and matter reaching the planet.
- Tidal forces: The gravitational pull of the Moon and other celestial bodies can cause small changes in Earth’s speed as it orbits the Sun. These changes are known as tidal forces.
- Relativity: Einstein’s theory of general relativity predicts that gravity affects not only the motion of objects with mass, but also the motion of light. Therefore, the speed of Earth around the sun is affected by the mass and energy density of the Sun.
- Other celestial objects: The presence of other celestial objects such as asteroids, comets or even passing stars can affect Earth’s orbit and its speed.
It’s worth noting that while these factors can affect Earth’s speed, they have relatively small effect on it and the orbit remains relatively stable over time. Also, scientists use these facts to study the universe and predict the motion of celestial bodies.
How fast Earth Moves? Let’s try again!
We know now how fast the Earth moves around the Sun, but that’s not the only motion. The Sun is also moving inside our Galaxy, and our Galaxy, the Milky Way, moves also in the Universe.
The Sun is at the center of our Solar System and all the planets, including Earth, orbit around it. The Sun is also not stationary, it moves in relation to other stars in our galaxy, the Milky Way. Let’s see how fast Earth moves in our Galaxy and outside of it. The Sun’s movement is complex and has various components, including:
- Orbital motion: The Sun orbits the center of the Milky Way galaxy at an average speed of about 220 km/s (about 490,000 mph). This motion takes about 225-250 million years to complete one orbit, known as a galactic year.
- Rotation: The Sun also rotates on its axis, much like Earth does. The rotation period at the equator is about 25.4 days, but it varies across the surface of the Sun.
- Differential rotation: The rotation period of the sun also varies depending on the latitude, the equator rotates faster than the poles.
- Solar wind: The sun also releases a stream of charged particles known as the solar wind, this stream can move at speeds of up to 750 km/s (about 1.7 million mph)
- Movement in relation to other stars: The sun and the solar system are not stationary, they are moving in relation to other stars in the Milky Way galaxy. The sun is moving in the direction of the constellation of Hercules at a speed of about 20 km/s (about 44,700 mph).
It’s important to note that while the sun’s movement is complex, it’s not random, it follows the laws of physics and the gravitational pull of other celestial bodies in the galaxy.
The Milky Way galaxy, like all galaxies, is in motion. The movement of the Milky Way is complex and has various components, including:
- Orbital motion: The Milky Way is part of a galaxy cluster known as the Local Group, which contains over 50 galaxies. The Milky Way and its neighboring galaxy, Andromeda, are moving towards each other at a speed of about 110 km/s (about 248,000 mph).
- Rotation: The Milky Way also rotates, much like the Sun and Earth. The rotation period at the galactic center is about 225-250 million years.
- Movement in relation to the cosmic microwave background: The Milky Way, along with the entire observable universe, is moving away from the cosmic microwave background radiation at a speed of about 371 km/s (about 828,000 mph) in the direction of the constellation of Leo.
- Movement in relation to other galaxy clusters: The Milky Way is also moving in relation to other galaxy clusters such as the Virgo Cluster at a speed of about 614 km/s (about 1.37 million mph) in the direction of the constellation of Virgo. That’s how fast Earth moves towards the Virgo Cluster as part of the Milky Way.
Conclusion: how fast Earth Moves?
- How fast Earth moves around the Sun: 29.78 km/s
- How fast Earth moves in our Galaxy: 220 km/s
- How fast Earth moves towards the Virgo Cluster: 614 km/s
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