You may feel that you know all the facts about Earth, but you are almost certainly wrong. It’s not surprising either, since there is a lot to know about our home among the stars. In this post, we will shed light on some of the more interesting, or surprising, facts about Earth.
1 Earth was once thought to be the centre of the universe
Ancient scientists believed that the Earth was still and that other celestial bodies moved around it. However, Copernicus later proposed that the Sun was at the centre of the universe, which is also not true.
Galileo Galilei observed and noted that Earth and the other planets revolved around the sun. For this perceived heresy, the Roman Catholic Church sentenced him to life imprisonment in 1633.
2 It doesn’t take Earth 24 hours to rotate
It’s actually 23 hours, 56 minutes, and 4 seconds. This is how long it takes for the Earth to completely rotate around its axis. Astronomers call this a sidereal day.
What this means is that a day is 4 minutes shorter than we think it is. Earth’s rotation can be affected by several factors, including the gravitational pull of the Moon and Sun, so a day’s length can vary regardless. This means that the difference is not drastic over time.
3 More facts about Earth – a year isn’t 365 days
An Earth year is actually 365.2564 days. The extra .2564 days created the need for leap years. That’s why we add on an extra day in February for every year that is divisible by 4 (2024, 2028, 2042 etc). That is, unless it’s divisible by 100 (1900, 2100, et) or by 400 (1600, 2000, etc).
Julius Caesar introduced the first leap year around 46 B.C., but his Julian calendar had only one rule: Any year evenly divisible by four would be a leap year. That created too many leap years, but the maths wasn’t tweaked until Pope Gregory XIII introduced his Gregorian calendar more than 1,500 years later.
4 Earth has a powerful magnetic field
This phenomenon is caused by the nickel-iron core of the planet, coupled with its rapid rotation. This field protects the Earth from the effects of solar wind. The solar wind is a stream of charged particles that is constantly flowing out from the Sun. Without the magnetic field, these particles would strip away the Earth’s atmosphere and make it uninhabitable for life as we know it
Earth’s magnetic field also plays an important role in the formation of the auroras, which are beautiful displays of light that can be seen in the polar regions of the Earth.
5 Among the facts about Earth is that our home is pretty old!
Our amazing planet has been around for quite a long time. By researching the rocks of our planet, scientists have calculated the Earth to be around 4.5 billion years old!
Scientists were able to age our planet by using radioactive dating techniques to determine the approximate ages of Earth’s oldest known rocks and minerals.
6 We are probably alone in our solar system
Some facts about Earth you may already be aware of, such as “our planet is the only one in our solar system that is known to support life”, but do you know why? It is because it has two very important things that living creatures need to survive: lots of oxygen and lots of water!
Earth’s distance from the sun means it sits in an ideal position for life to form and thrive because it doesn’t get too hot or too cold.
7 Our planet is ridiculously fast
As with all the planets in our solar system, Earth orbits the Sun. And it does so at an insane speed: approximately 18.6 miles (30 kilometres) per second, in fact! It takes a little over 365 days (one year) for the Earth to complete one full orbit of the Sun.
The fastest planet in the Solar System is Mercury, which orbits the sun at an average speed of 105,941 mph (170,496 kmh). Mercury completes a full orbit of the Sun every 87 days, 21 hours.
8 Facts about Earth and the dark side of the Moon
Another interesting fact about Earth is that the same side of the moon is always facing the planet. This means the moon is in synchronous rotation with the Earth. In other words, they rotate on their respective axis at the same time.
Depending on where you are in the world, the Moon may look upside down when compared to viewing it from another part of the world.
9 Earth and the Sun are used as a unit of measurement
Earth is exactly 1 AU from the Sun, which makes sense when you stop and think about it. AU (which is the distance from the Sun to Earth) is the standard unit of measurement. It is used to measure the distance of celestial bodies from the Sun, and Earth’s measurements are used as a standard
Farfarout, a planetoid, is our solar system’s most distant known object and sits at a distance of 131.686366 AU, or 19.7 billion kilometres, or 12.4 billion miles.
10 Earth has unknown minerals
Scientists recently calculated that there are over 1500 minerals that are still undiscovered somewhere on Earth. We are currently aware of more than 5000 minerals, but many are still unknown to us.
Another interesting fact is that Earth’s mineral diversity is unique to itself and is not duplicated on any other planet.
[…] 10 Facts about Earth […]