Astronomy is the scientific study of celestial objects like stars, comets, planets and galaxies. It is derived from Greek words astron and nomos which mean 'star' and 'law' respectively. It is related with formation and development of the universe, motion of celestial objects, evolution, physics and chemistry.Since the 20th century, the field of astronomy has got divided into two branches: observational and theoretical. Observational astronomy emphasis on acquiring and analyzing the data by using basic principles of physics. Whereas, theoretical astronomy focuses on the development of computer or analytical models to explain astronomical objects and phenomena. Both these branches compliment each other. Fun Facts About The Sun The Sun is 4.5 billion years old and produces 383 billion trillion kilowatts of energy. Sunlight takes 8 minutes to reach the Earth and is responsible for the ocean currents and weather patterns on our planet. The Earth orbits the Sun in an elliptical uneven orbit and the distance between them varies depending on where the Earth lies in that orbit. The Sun is only an average size for a star but still accounts for 98% of the total matter in our solar system. The solar winds produced by the Sun extends to about 50AU, where AU is the distance from the Earth to the Sun. The lightning in the sky is nearly 3 times hotter than the Sun. Fun Facts About The Moon
Moon is the only non-Earth object upon which a man has walked. Dr. Eugene Shoemaker's love for the moon was so much that after his death, his ashes were scattered over the moon by the Lunar Prospector spacecraft in 1999. The giant footprint left on the moon dust by astronaut Neil Armstrong is believed to be the oldest footprint. Every year the moon is moving away from the Earth by 3 cm.
Fun Facts About Stars
There are nearly 1 x 10 ^22 stars in the universe.
Some of the stars in the sky are so far that the light from them takes million of years to reach us. Proxima Centauri is the closest star to our solar system and is nearly 4 light years away. Inside the nebula, when gases and dust condense, a new object is formed which is known as protostar. Depending upon how hot the white dwarf star is, its color varies from blue, white, yellow, or red. Supernova explosions are capable of destroying an entire star. Pulsar, a neutron star which was discovered in 1967 emits radio waves. Polaris, the north star, is the only star in the sky that doesn't appear to move from night to night. Fun Facts About Planets
Mercury is the second smallest planet in the solar system and has no moon. It can get as hot as 800º C and cold as 300º C below zero. One year on Mercury is equal to 88 days on Earth. It is named after the Roman God of Commerce. Venus is the only planet that rotates from east to west. A year on this planet is equal to 225 days on Earth. Earth is nearly 93 million miles away from the Sun. It takes about 16 million horsepower to break the Earth's gravitational pull. According to scientists, in around 5 billion years, a day on Earth will be 48 hours long and somewhere during that time the Sun will explode. The planet Neptune was discovered more than150 years ago in 1846, and since then it still has to complete an orbit around the Sun, as one Neptune year equals to 165 Earth years. Pluto does not have a fixed orbit and its orbit comes in the middle of Neptune's orbit. Also, Pluto's size is very small which made scientists demote it to a dwarf planet status. Astronomy can be considered as an interesting science filled with many fun and interesting facts. Whether it's the size or temperature of a star, the Sun, distant planets - anything and everything once discovered is recorded. This information can be retrieved to entertain and enlighten people.