Stars have always caught the imagination of the human brain even before it started realizing its own potential. The very sight of the dim, sparkling light amidst the dark blanket is not just appealing, but soothing as well. Numerous poets, writers, romantics spent days imagining adjectives that resonated with the sheer beauty of the pearl that hung in the sky. And it is not the just the poets who felt that their creative desires were fulfilled because of it, a certain Polaris star has given the idea of the direction for centuries where even veteran eyes failed.
Here are some amazing facts about Stars:
1. Stars Don’t Twinkle
One can blame Jane Taylor for initially making us believe about the twinkling with her famous “Twinkle Twinkle Little Star” rhyme, but it is understandable. It took 3 centuries for mankind to realize that it is Earth’s atmosphere that causes the apparent twinkling. As the light emitted from the stars enter our atmosphere, it has to go through several layers with differing density. This causes a phenomenon named Diffraction. Now when the light goes through such layers, it starts bending away from its original path, which causes to change it in intensity and the color of light which enters inside our eye.
2. They all Start the Same.
Don’t be surprised. Despite of existing mammoth distinction in size and color, all the stars are formed from the cold molecular Hydrogen cloud as they collapse in gravity. After the collapse, it fragments turn into individual stars. Initially, ratio of the gas was 75% Hydrogen and 25% Helium during Big Bang, however, a material is formed into a ball that keeps collapsing under its own gravity till it can create Nuclear Fusion at its core. But over the course of time, stars convert the Hydrogen into Helium. However, all the stars begin with 3/4th of Hydrogen, 1/4th Helium with a trace of other elements.
3. But then, Who’s Who?
Scientists categorize stars on the basis of special characteristics they possess. On the basis of information contained in the light radiated, stars are categorized as O, B, A, F, G, K, M, R, N, T, Y; while the group of stars is recognized on basis of temperature, luminosity, and color. O and B are blue looking and generally the hottest stars, and R, N, T, Y are the brown dwarfs which are too cool to be categorized as stars.
4. There are No Green Stars.
While the spectrum of released colors include green and our sun itself is a green-blue star; however, there is no such thing as Green Star. While the wavelength of our sun varies between blue and green due to the surface temperature of the Sun, and once in contact of a human eye, we see the light as white or yellow in color. The same phenomenon applies to other stars too, our eyes mix green and blue with other colors, thus making it difficult to recognize. So if someone claims to see a green star like Beta Librae through their telescope, it is probably an optical illusion.
5. Stars are Black Bodies
Black bodies are a hypothetical perfect absorbent and radiator of energy, with no reflecting power. However, a star absorbs all the electromagnetic radiation that falls over it and gets radiated back into space with more intensity. This is why there are so many colors for stars. While a cooler star and they radiate the waves in red wavelength, a hotter star emits a wavelength in yellow/green half of spectrum. Its infamous cousin though, Black Hole absorbs all the radiation without glowing any light what so ever.
6. Black Holes Don’t Suck
Speaking of Black Holes, it is a common misconception amongst the misinformed; they are widely thought as vacuum cleaners, sucking everything around them inside their mystique black belly. But it is not so. There is no suction involved in Black Holes, instead, a very strong gravitational attraction pulls the matter inside them.
Most common types of stars are red dwarfs. These tiny dwarfs, about 167,000kms are only 20% bigger than Jupiter. Small, aren’t they? But these dwarfs are like a slow-burning lamp. With a lifespan of 10 trillion years, scientists believe that every 20 out of 30 stars near to Earth are Red Dwarfs. Staying true to their name, these stars can be a bit too difficult to be recognized from the naked eye. This is due to the low temperature they possess inside them, which causes a low emission of light.
When a star finally runs out of energy, it simply doesn’t disappear into the dark fabric of space. Instead, it explodes and bombards its particles in every possible direction, leaving us with unparalleled brightness, thus becoming a Supernova. And when Supernova explodes, it unleashes countless nuclear reactions. Scientists believe that Supernovae’s reactions are the reason why Earth has elements heavier than Iron. This is also because the center of Supernova is like a super laboratory in itself. The center of it can accelerate particles a thousand times faster than the Large Hadron Collider, which effects the excitation of the particles needed to form a new element.
9. The Shining star
Unlike the red stars, O Stars are make up the minority the of the population in the galaxy. But they possess a violent phenomenon with them which makes it to have a disproportionate effect on its surroundings. The winds and shocks coming from O stars can both trigger and stop star formation. And their supernovae enrich galaxies with heavy elements crucial for life.
10. It’s all about the size!
As big as our Sun looks like, it is tiny as compared to other stars present in our galaxy. There are plenty of stars that are thousand times bigger than the sun and have a mass of more than 100 times than our star in the solar system. One of the largest known supergiants, VY Canis Majoris is up to 2100 times the size of the sun. And it’s nemesis? UY Scuti. With a radius of 1,708 solar radii and volume of nearly 5 billion times more than that of Sun. It is so huge, if we place it in the center of Solar System, its photosphere will engulf the orbit of Jupiter! Pistol Star is about 100 times brighter than Sun, but it is 10,000,000 times brighter. This young star is another blue hypergiant star is approximately 25,000 light years away from Earth, in direction of Sagittarius. It would be visible to the naked eye as a fourth magnitude star if it were not for the interstellar dust that completely hides it from view in visible light. Let’s not forget that despite complaining about the scorching heat every day, Sun is not exactly the hottest star in the Milky way! One can only imagine.