Difference between stars and planets
Stars vs planets:
The universe is commonly defined as the totality of everything that exists or is known to exist. This includes all matter and energy; planets, stars, and galaxies; and the contents of intergalactic space. Among the content of the universe, planets and stars are the most confusing objects as they appear to be the same. Despite their appearance, they have many differences, which are not noticeable to a naked eye. Therefore, his article will brief the differences between stars and planets providing a description on what they really are.
What are stars?
Stars have been forming since the Universe began. Stars change over time. It may take millions to billions of years for a star to live out its life. Basically, stars are big exploding balls of gas, mostly hydrogen and helium, which gives off both heat and light. Stars shine by burning hydrogen into helium in their cores. This luminous sphere of plasma held together by gravity. The huge reactions taking place in stars are constantly releasing energy (called electromagnetic radiation) into the universe, which is why we can see them and find them on radio telescopes such as the ones in the Deep Space Network (DSN). Stars are the most widely recognized astronomical objects, and represent the most fundamental building blocks of galaxies. A galaxy contains clouds of dust and gas, as well as stars. The star which is nearest to earth is sun. We can see near about 2500 stars on a clear night with our naked eye. But in actual, total no of stars are countless. A star begins as a collapsing cloud of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. After a star runs out of fuel, it ejects much of its material back into space. New stars are formed from this material. So the material in stars is recycled. Stars emit radiations having different wavelength. Spectrum of all stars is continuous. Stars may or may not be of same colour. The spectrum lines generated depends upon the star colour. This is the main reason that the different stars have different spectrums. Some stars even orbit around each other. Such stars are called binary stars.
What are planets?
Planets are the end product of disk accretion around a primary star or sub-star. Apparently, a planet is a large, round object in space that moves around a star. Greek astronomers employed the term asteres planetai, which means “wandering stars”, for objects which apparently move over the sky. This term developed to form the term ‘Planet’. However, the term planet is ancient, with ties to history, science, mythology, and religion. Although there is not any specific definition for the term ‘Planet’, it can be simply described as “an object resembling the planets in the Solar System, which is orbiting a star”. Planets couldn’t form until the first stars ran out of fuel and exploded into supernovas, about 14 billion years ago. The supernovas spewed out thousands of tons of carbon, oxygen, iron and other elements into space. Planets are made out of the recycled atoms of old stars. Planets are generally divided into two main types: large, low-density gas giants, and smaller, rocky terrestrials. Earth and the other three inner planets of our solar system (Mercury, Venus and Mars) are made of rock, containing common minerals like feldspars and metals like magnesium and aluminium. The other planets are not solid. Jupiter, for instance, is made up mostly of trapped helium, hydrogen, and water. In our solar system, the four “gas giants” are Jupiter, Saturn, Neptune, and Uranus.
What is the difference between planets and stars?
Although planets are made of expired stars, both these astronomical objects have their own features. Above all the brightness differs. Stars since they have hydrogen burning into helium in their cores shine brightly. But planets, which are made of rock or any metal, do not have such burning on them and therefore, they do not shine. But we see them in the night sky as they reflect the light of the sun. When stars shine, they twinkle as a result of the above mentioned burning in them. But, as planets only do reflect the light of the sun, they do not twinkle as stars do. Moreover, the relative positions of stars do not undergo any change. They do not circulate around another planet either. The mostly used example to prove this is the Sun, as sun is the closest and the most observed star in the galaxy milky way. But this completely differs, when it comes to planets. Planets usually change their position. Since planets are held together with a star by the gravity, they do not float away, but still they go around the star they are connected to. This can be learned using our galaxy. The motion of planets in the Milky Way, around the sun is noticeable as a daily shifting of their relative positions in the sky.
Stars are so far away from the planet earth that they cannot be observed closer, with the use of a telescope, but brighter can they be explored. Planets on the other hand, can be magnified by a telescope as they are nearer to the planet earth than stars do. Stars, as a result of the burning of gas on them, have very high temperature, while planets are low in temperature. One can observe billions of stars in the celestial sphere. While stars appear to be large balls of burning gas, planets sometimes come with water as well. Planets normally have more intense colours than stars. Mercury is greyish-orange, Venus is yellow, Mars is blood-red, Jupiter is silver, Saturn is yellow, and Uranus and Neptune are blue. Aldebaran and Antares are also reddish.