The age of the dinosaurs followed 225 million years later, and human beings evolved less than one million years ago. Above Earth's solid surface lies its atmosphere. The atmosphere has more oxygen today than it did when Earth formed. While the early atmosphere was mostly carbon dioxide, more than three-quarters of Earth's atmosphere is now nitrogen, and most of the rest of it is oxygen. Chemical reactions locked much of the early carbon dioxide inside rocks, while plants produced the oxygen in our present-day atmosphere.
Human technology is another factor that sets Earth apart from other planets.
Thousands of artificial satellites orbit our planet, enabling humans to communicate with one another, monitor the weather, and, sometimes, keep an eye on other people. The oxygen in the atmosphere allows you to breathe comfortably, and the Sun keeps you warm in the daytime. By watching the sky, you can see changes in Earth's atmosphere, as clouds form and move, rain falls, and lightning strikes. Water droplets in the atmosphere produce rainbows when sunlight passes through them at the proper angle. People in the far north and south can see fantastic displays of light called aurorae, caused by energetic particles from the Sun trapped in Earth's magnetic field.