Facts About Universe

Universe is commonly defined as the totality of everything that exists including all physical matter and energy, the planets, stars, galaxies etc.

• Universe is about 13.7 billion years old ( accord. to big bang theory ).
• Milky Way galaxy contains about 300 billion stars.
• Andromeda is our nearest galaxy.
• There may be a huge Black Hole in the middle of most of galaxies.
• The size of Solar System is estimated about 10^5 AU.
• Actual colour of the Sun is White.
• Whole universe is made up of 75% Dark Energy, 21% Dark Matter & 4% of Normal Matter.
• According to Astronauts Space smells like Hot metal, Welding Fumes.
• The Great wall of China is not visible from space.
• Light Year is the unit of length and is equal to the distance traveled by light in 1 year.
• Speed of light in vaccum is  3 x 10^8m or 3,00,000 km/sec.
• Black Hole is formed when giant star run out of fuel and collapse under its own weight .
• Light cannot escape the intense gravitational pull of a blackhole.
• Every basic elements made in stars.
• Every atom in our body come from stars .
• The milky way have for spiral arms not two.
• Atoms are mostly empty space (about 99.9%).
• It takes photon an average 17000 years to travel from core of sun to surface and 8 minutes to reach earth from surface.