Large Cosmos

  Our home is Earth. But maybe we won't stay in Earth. Population is increasing rapidly. And global warming is important problem. Our earth’s temperature is going up. 100 years later, Earth’s temperature will maybe go up 6 degrees. And we'll go to cosmos. Earth is narrow. We will go to Moon and Mars. So we should study and research about cosmos. And we should interested in cosmos. Our Earth is narrow. Earth’s equatorial radius is about 6300km. But Sun’s radius is 700000km. Sun’s radius is 109 times longer than Earth’s radius. And our Solar system’s radius is 50000AU. AU is 150000000km. And our galaxy’s radius is 100000 light-year. Light year is length that light going one year. Light’s speed is 300000km/s. 1 light-year is about 9000000000000km. Our cosmos is large. Our cosmos is swelling rapidly faster than ligth. So we can see only one part of the cosmos. If you are young, you will be explore the large cosmos