How did Earth get its name?
All of the planets, except for Earth, were named after Greek and Roman gods and goddesses. The name Earth is an English/German name which simply means the ground. It comes from the Old English words ‘eor(th)e’ and ‘ertha’. In German it is ‘erde’. The name Earth is at least 1000 years old.
Why does Earth spin?
Earth spins because of the way it was formed. Our Solar System formed about 4.6 billion years ago when a huge cloud of gas and dust started to collapse under its own gravity. As the cloud collapsed, it started to spin. Some of the material within this cloud gathered into swirling eddies and eventually formed into planets. As the planets formed, they kept this spinning motion. This is similar to what you see when skaters pull in their arms and spin faster. As material gathered in more closely to form a planet, like Earth, the material spun faster. The Earth keeps on spinning because there are no forces acting to stop it.
How much water does Earth have?
There are more than 326 million trillion gallons of water on Earth. Less than three percent of all this water is freshwater and of that amount, more than two-thirds is locked up in ice caps and glaciers.
What keeps our atmosphere attached to Earth?
Our atmosphere is a mixture of gases that surround Earth. It is kept in place by the pull of Earth’s gravity. If Earth was a much smaller planet, like Mercury or Pluto, its gravity would be to weak to hold a large atmosphere.
What is the atmosphere of Earth made of?
Earth’s atmosphere is 78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide with very small percentages of other elements. Our atmosphere also contains water vapor. In addition, Earth’s atmosphere contains traces of dust particles, pollen, plant grains and other solid particles.
What are the highest and lowest temperatures on Earth?
The highest temperature ever recorded on Earth was 136 Fahrenheit (58 Celsius) in the Libyan desert. The coldest temperature ever measured was -126 Fahrenheit (-88 Celsius) at Vostok Station in Antarctica.
How much does Earth weigh and how is this measured?
Earth weighs about 13,170,000,000,000,000,000,000,000 pounds (or 5,974,000,000,000,000,000,000,000 kilograms). Since Earth is too big to be placed on a scale, scientists use mathematics and the laws of gravity to figure out Earth’s weight.
What is Earth made of?
The Earth is made out of many things. Deep inside Earth, near its center, lies Earth’s core which is mostly made up of nickel and iron. Above the core is Earth’s mantle, which is made up of rock containing silicon, iron, magnesium, aluminum, oxygen and other minerals. The rocky surface layer of Earth, called the crust, is made up of mostly oxygen, silicon, aluminum, iron, calcium, sodium, potassium and magnesium. Earth’s surface is mainly covered with liquid water and its atmosphere is is mainly nitrogen and oxygen, with smaller amounts of carbon dioxide, water vapor and other gases.
How large is Earth?
Earth’s circumference (the distance all the way around the equator) is 24,901 miles (40,075 kilometers). Its diameter (the distance from one side to the other through Earth’s center) is 7,926 miles (about 12,756 kilometers). Earth is slightly smaller when measured between the North and South Poles which gives a diameter of 7,907 miles (12,725 kilometers).
How old is Earth?
Earth is thought to be between 4.5 and 4.8 billion years old. The age of Earth is found by measuring the age of very old Earth rocks. This is done by measuring the rate at which elements of the radioactive metal uranium decay (break down) into lead. Scientists have also measured the age of meteorites which have fallen onto Earth’s surface, and the age of moon rocks brought back by the Apollo astronauts. Both the meteorites and the moon formed around the same time as Earth, and they show similar ages.