- Light ray travels at a speed of 3000,000 km/sec.
- The mass of sun is 2 × 1030 kg.
- Earth distance from moon is about 384400 km.
- One million (10 lac) earths could fit inside the sun.
- When all the colors of light are mixed together, the sun appears white to our eyes.
- The sun is mainly composed of hydrogen and helium.
- When the sun has burned all its hydrogen, it will continue to burn helium for 130 million more years.
- A satellite moving round the earth with a uniform speed has no acceleration at all.
- The total mass of the planet earth is about 6 × 1024 Kg.
- The shape of earth’s orbit around the sun is elliptical.