At night, when you look up high in the sky, you will observe trillions of glistening dots, out of which some come out brighter, some are bigger while some of them twinkle. It is a point to exclaim, what are these bright dots?
What Do These Dots Represent?
Well, the dots are Stars and Planets. On this page, we will learn about the following:
A star is a celestial body having its own light and energy.
A star is a huge glittering ball of hot gas, mainly consisting of Hydrogen and Helium.
Stars are giant, luminous spheres of plasma collapsed together by gravity.
Stars are responsible for the manufacture of heavy elements like Carbon, Nitrogen, and Oxygen.
Star formation shapes the visual aspect of the universe and provides the sites for planets. Especially in astronomy.
The Life cycle of a Star
Stars are born within the clouds of dust and distributed all around most galaxies. A well-known example of such a dust cloud is the Orion Nebula. Stars commence forming as an impenetrable cloud of gas in the blazons of spiral galaxies. Individual hydrogen atoms descend with accretionary speed and energy toward the center of the cloud under the force of the star's gravity. Strum und Drang deep within these clouds gives rise to slubs with sufficient mass that the gas and dust can begin to collapse under its own gravitational attraction. The increase in energy heats the gas. When this process has extended for some millions of years, the temperature reaches about 20 million degrees Fahrenheit. At this temperature, the hydrogen within the star ignites and burns in a perpetual sequence of nuclear reactions, the material at the center begins to heat up.
Our nearest star, the Sun is so hot that a huge amount of hydrogen undergoes the star-wide nuclear reaction, like in a Hydrogen bomb. Even though it is incessantly exploding in a nuclear reaction, the Sun and the other stars are so huge that it will take billions of years for the explosion to use all the fuel in the star. The external pressure of the gas heated by fusion is balanced by the inward pull of gravity, leaving the star in Hydrostatic equilibrium. This hydrostatic equilibrium remains balanced in most of the star’s life by maintaining its temperature steadily. The life cycle of any star from birth to death and all these stages in between would span billions of years. That’s why stars don’t seem to change at all because of a human morsel in the blink of an eye to these goliaths.
A planet is a celestial body that orbits around the Sun, has adequate mass for itself-gravity to get on top of rigid body forces so that it assumes a hydrostatic equilibrium to make it round, they are smaller than stars. Planets reflect light from the sun and don't have their own light. These do not twinkle, unlike the stars. Planets are closer to the earth's atmosphere so the light reflected from the planet directly passes through the atmosphere and doesn't bend much because of the distance and hence does not twinkle. This is a major observational distinguishing feature of a planet and stars. The planets are seen to be changing their position frequently when seen from the earth's surface.
There are Two Categories of Planets in Our Solar System:
Inner Planet: The planets which are close to the Sun are Mercury, Venus, Earth, and Mars.
Outer Planet: After an asteroid belt comes the planets that are at a far distance from the Sun are Jupiter, Saturn, Uranus, and Neptune.
Difference Between Stars and Planets
Now, let us have a look at the major differences between the stars and planets:
Luminous objects are those objects which emit their own light, a star like the Sun, an electric bulb while the non-luminous objects take light from an external source to shine such as Planets, the Moon. A distinguishing quality of Stars is that they twinkle because as the light of stars descends on the Earth it passes via Earth’s atmosphere and as a result of atmospheric refraction, they appear to twinkle. The Planet is a Greek word (Planetes) which means ‘Nomadic’. All of the planets apart from Earth were christened after Greek and Roman Gods and Goddesses.