Falling stars are quite fantastic to witness, quick flashes of light that make you wonder what happened to the star that fell.
There are many legends and superstitions surrounding the falling star, some believe that a fallen star is good luck and that when you see one you are actually seeing a soul that has been released by purgatory.
In other places, a falling star is said to represent the soul of an infant that is to be born. Regardless of what you might believe, it is true that falling stars occur, but, why? What is the reason for a heavenly body to lose its place in the heavens?
In this article, we are going to learn about this very topic. So, without further ado, let us begin, and find out what causes stars to fall.
What Is A Star?
What is a star? A twinkling light in the night sky? Stars are far more complicated than that. In fact, the definition of a star is an object which is large enough that it can ignite the fusion of certain elements in its core. This ignition is usually a result of the gravitational pull within the object.
One of the smallest objects that qualify to be a star by this definition is only 10% of the mass of the sun.
The stars that are the smallest are commonly known as red dwarfs, this is because they are small and emit red light. These stars burn hydrogen at their core and in the infrared portion of the electromagnetic spectrum radiation is released.
It is because of this process that these stars appear red. Red dwarfs are the most common star in the Milky Way, they are so small that even the closest star which is named Proxima Centauri is not visible to the naked eye.
Another type of common star is ones like our sun, they are a medium mass star with a medium life and a medium brightness. The radiation that these stars emit is white, but because of the blue atmosphere of Earth, we see our sun with a light yellow tint.
Stars bigger than the sun are known as giant stars, this type of star is actually quite rare. Their size and brightness make them easy to spot, but there are not a lot of these giants in our galaxy.
A fun fact about stars is that the majority that you see when you look up at the night sky, most of the stars that you see are actually bigger than the sun. The biggest stars out there have a blue tint, this is because the amount of energy that the radiation that is emitted is much more than ultraviolet light.
The Stripe Known As The Main Sequence
Other than red dwarfs, white stars, giant stars, and blue stars, there are actually a wide variety of stars that fit between these main categories. For example, you get some large stars that are red. Many years ago, when astronomers first started mapping the sky and studying its contents, they were unable to find any meaning behind a star’s color, size, or brightness. It all seemed a bit random, and they were stumped for a long while.
They eventually found a solution to this starry conundrum; the answer was found in a diagram known as the ‘Hertzsprung-Russell’ Diagram. This revolutionary diagram is now at the center of a lot of things we have learned about the stars and is even used today. It plots the temperature of the stars. But, how do you know what the temperature of a star is?
Well, the color of the flame can tell us a lot about how hot a flame is. For example, a blue flame is the hottest while red is the coolest. In addition to the color of the star. You can tell its temperature by how bright it is. Using these two things, you can roughly guess what a star’s temperature is.
With this in mind, if you plot the temperature and brightness of several stars and make a point for each on a diagram, you can actually learn quite a lot. Using the Hertzsprung-Russell Diagram, astrologers have found that stars have a stripe that goes diagonally through them and by far the majority of stars live on this line.
This is known as the ‘Main Sequence’, stars that have hydrogen cores, which is most stars, will likely be somewhere within this stripe. As a star gets older they slowly move up along the main sequence, and as they do, they get brighter and bluer as time goes on.
How long they burn for and stay in the main sequence is dependent on how big they are. For example, a low mass red dwarf star can spend trillions of years in the main sequence, but a giant star may only last several million years if it is doing well.
Once the fusion source, in most cases this is the hydrogen in the core of the star, it will move off the main sequence and will evolve in several different directions. Bigger stars become red giants that will have their own positions within the Hertzsprung-Russell Diagram.
While other stars may go back and forth, changing between blue and red as heavier elements try to fuse in their cores.
What Causes Falling Stars?
Now that we know a bunch about stars, we can learn about what causes a star to fall, and I fear the truth of it is far less to do with stars than you think. In space, there are a lot of pieces of rock, dust, and debris that float around. Every so often, some of this debris will enter the very top of the earth’s atmosphere. They burn between 65 and 135 kilometers above the earth’s surface.
These rocks or debris travel quite fast and when they enter or crash into our atmosphere they burn up. The earth circles around the sun at about 29 kilometers per second around the sun. With the debris moving at 40 kilometers per second, the speed of the earth and the debris have a combined speed of between 30 and 70 kilometers per hour.
This is the point we actually see the debris and rock, which, when they burn, look like falling stars. What we really see is the tail of this debris, which gives off that falling star effect.
Because our solar system is full of dust, debris, or meteors, the earth is in constant contact with them as it moves around the sun. Because of this, there is a phenomenon known as sporadic meteors, which means that about 10 shooting stars or falling stars hit the atmosphere an hour.
When we get a meteor shower, it simply means that a dense section of dust or debris has hit the earth’s atmosphere and as they repeatedly collide we get that beautiful shower of shooting stars.
When a meteor shower happens, they are often named after the part of the sky they came from. This can mean that the constellation radiant where the meteor shower was first located could become that shower’s name.
But, because of the way the earth moves, you can have a tricky perspective and the debris can appear to come from the same vanishing point. For example, what it shows, and it looks like snowflakes are coming from a tunnel when you drive through.
There are many meteor showers that have been named, like the Perseids, Leonidis, Geminids, and many others. Constellations have lent their names to meteor showers over the years.
That is all for this article, we hope that you have learned a lot about stars and why they fall…or…what creates that falling star effect. There is a lot you can learn about the Milky Way and everything else in our galaxy, the idea of stars and falling stars is just scratching the surface.
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