Earth is the third planet from the sun and it is about 93,000,000 miles away from the sun. It is the only planet known to support life. It takes 365 ¼ days for the earth to make one trip around the sun. The earth revolves around on its axis once every 23 hours, 56 minutes, and 4.1 seconds. Almost 70 percent of the surface of the earth is covered in oceans. Scientists have estimated the earth to be about 4.65 billion years old. The most common element on the earth is oxygen, about 46.6 percent of the total. The next common element is silicon, comprising 27.7 percent of the total. Other common elements include aluminum, iron, calcium, sodium, potassium, magnesium, titanium, hydrogen, phosphorus, and carbon.