Astrology The Earth is our home in the universe. It is the third planet from the sun and has an atmosphere made mainly of nitrogen andoxygen. Seventy percent of Earth's surface is covered by water. The rest is land: mountains, volcanoes, plains, deserts, forests and valleys. Earth fact file: Diameter (width across equator) 12,756 kilometers Average distance from the sun: 149,600,000 kilometers Average temperature: 22 degrees Celsius. Surface gravity (Earth equals 1) 1 Sample Heading 3 This is where you tell your story or provide information to your visitors. Be sure to include changes or new information in a timely fashion. By keeping your Web site up to date, visitors will have a reason to return often. You may add text or HTML code to this field and make it as complex as you want. Or, you may erase the content of this field causing it to be hidden when people visit your site. Sample Heading 4 This is where you tell your story or provide information to your visitors. Be sure to include changes or new information in a timely fashion. By keeping your Web site up to date, visitors will have a reason to return often. You may add text or HTML code to this field and make it as complex as you want. Or, you may erase the content of this field causing it to be hidden when people visit your site.