Hello Star 🌟!

I literally mean that, yes i mean YOU. Bcz look around everything you see can be broken down to atoms and your every atom from tip to toe,is completely made from the stars in the sky.

Yes! You are completely made up of Stardust, so technically you are already a STAR. the elements like oxygen,carbon, hydrogen, nitrogen, calcium and every bunch of other elements which are in your body, completely came from the stars. To be clear they came from the dying stars. Yes! Dying stars. Stars too die. They have birth they have life and they have death too. But they differ from us in the life expectancy. We may live for like 60-100 years maximum but the stars live for like billions billions and billions of years. It’s all Big Bang! That we are stars. We’ll go deep in to it later but now let’s talk about Space.

What do you think is the fastest thing on our entire solar system ? And all the scientists banging there heads to overcome that speed? Any guess ? It’s the light.🔥. Yes! Even your phone torch light. The light is the fastest thing we have ever known from the dawn of human civilization to this present day. But theories suggest that space is really huge, vast and it is constantly expanding faster and faster than the speed of light (3×10*8 m/sec). It’s like Space is infinity, you give me the biggest number you could ever think of and it is always close to zero than to infinity. In the same way you can think of how much ever distance you want, but it’s always near to zero than to the actual size of the universe. With that said,see the below image to have rough idea about how big the universe is and…

There are multiple billions of universes like that in space. It is hugely vast than we can comprehend.

Formation of stars

Although we see Space as a empty thing it is actually full of hydrogen in it. These hydrogen atoms are notorious and doesn’t stay calm, they roam here and there and form clumps , many clumps again combine together to form group’s, as these clumps get bigger and bigger their gravity gets stronger and stronger, this gaint cluster of gas and hydrogen combined together is called “nebula“(Normally many believe nebula is the starting point of formation of stars) and after some billion years of adding mass and increasing gravity they start Falling in to the centre of it’s own mass (due to Quantum gravitational field) and they keep on falling inside in to the mass – Imagine a coffee cup and the ocean, and all the water in ocean is falling in to the coffee cup constantly (although the cup has to break out due to density of water, it cannot do it -due to the gravity) as they keep on falling in to it rapidly, there is increase in speed, causing ,increase in heat (inside centre)more the heat,more the speed and more the speed,more the heat,the process goes on and on and on like a never ending circle for like billions billions billions and billions of year’s and at a point due to the massive speed and heat, The hydrogen atoms undergo Nuclear fusion (that is a process where two atoms get united and form a new one) here two hydrogen atoms combine to form a new element called “Helium”. Nuclear fusion creates small mass in to enormous energy – a peanut of mass would be converted to an explosion of roughly 22,000 tons of TNT! 😵 and this nuclear fusion is constantly happening in our very own star (sun) and also in the rest of stars in our universe! Emitting large amounts of energy.

As we all know second law of thermodynamics which states – energy is neither created nor destroyed. You may ask what’s with thermodynamics now? But in the process of forming helium… there’s net release of extra energy, because the total mass of the new single nucleus (helium) is less than the mass of the two original nuclei combined(hydrogen). The extra mass becomes extra energy. And the energy released due to nuclear fusion tries to escape but relentlessly it constantly falls in to it’s own gravity again and again and again. After some billion years of falling in to gravity there’s a point where two forces i.e the gravity – inward force and energy- outward force become equal.

Imagine a balloon 🎈. The air inside it is constantly trying to get out of it and the balloon is constantly contracting to inside. So there are two pressures keeping the balloon in that state. In the same way the nuclear fusion energy tries to come out but the gravity is so strong that it holds the energy out of spilling.. it’s like contracting a huge Mountain to the size of a sand particle ( one can imagine how Massive and huge is the energy and how massive is gravity ) and slowly the fuel- hydrogen atoms and gas which are the main source of this nuclear fusion- run out (or) get used up, making gravity to win this tug of war, this gravity makes the star🌟 collapse inwards. It’s like something one million times the mass of Earth collapsing in 15 seconds! The collapse happens so quickly that the outer part of the star explodes and inner core gets contracted, (Imagine dropping a stone in pond,the stone creates ripples- here the stone is core and ripples are explosion) the collapse causes increase in pressure and temperature in the core of star! – at this stage one can say a star is in near to death stage– bcz it’s gonna transform in to a totally new one, If the fuel burnt out was of large star — it is called Red super gaint, and if the fuel burnt out was of small stars it is called — Red gaint. Even our Sun will convert in to Red gaint in about 5 billon years or so before expanding and killing planets.

Here mass plays a key role, the more the mass of a star the more it burns out quickly and small the mass of a star the more it survives. This is because of the thermodynamics, as we all know it takes more heat,more energy to burn large objects than small objects. in the same way, large stars require more energy and more heat to maintain its temperature to undergo nuclear fusion and so they use up most of its fuel quickly than the small stars. And all the above process doesn’t happen in a week or a month it takes literally billion billion billion billions of year’s. Thus the life of a star depends on how big they are! Meaning – mass plays a key role.

Our sun is a small star, so our sun🌞 may live for 10 BILLION years. (1000 crores of years!)

Keeping that aside the fate of REDGAINT depends on mass of a star.

If the star size is more than 1.5 times of our sun or 8times heavier than our sun then it transforms in to BLACK HOLE(as it is black) and if the star size is less than 1.5 times the sun or below 8 times heavier than sun then it transforms in to White Dwarf Star. (as it is dwarf in size and white in colour) Don’t assume white as something cool. it is actually a way hotter than you imagine! if you heat up a iron rod or something like that constantly for a period of time it changes colours from Red to orange to yellow and white. Indicating white is way hotter than red. Upon the more nuclear fusion reactions causing heating even our sun after red gaint stage will get in to white dwarf stage (white colour) and will continue to be in this stage for like 10 billion years, and dies of later in the form of gas and dust

With that said, let’s discuss about time.

Why are you discussing about “time” thing man ? Aren’t we suppose to discuss about stars and black holes.?

Yes you are right, we shall discuss about the stars and black holes stuff but To understandblack hole clearly(and it’s possibilities of time travel) we should know about time.

We humans have an interpretation of what past,present and future is based on our psychological time. We feel whatever happened in a few seconds back is past,the second which you are in RIGHT NOW is present and the next seconds which Haven’t came yet is future right ? Yes right for us. But not for all. Mainly for the things in Space. The space have different time compared to us! What do you think Einstein is famous for ? It’s for this differentiation that time is not absolute and it’s relative,and it increases or decreases with speed and gravity. In simple terms he said “Time runs slower when gravity increases” and “Time moves slower as you move faster“. and not everyone feels the same time as you do on earth with a person near black hole. ( these effects are mainly due to Quantum gravitational forces and – we’ll discuss that later.) Although you can make time slower but you cannot travel in to the future or past only because of the barrier of light. Unless until a person travels faster than light,He cannot go in to the past or future!

Now to the Black holes.

Black holes are divided into 3 categories based on size

1) Primordial Black holes — These are the smallest of black holes and range from an atom’s size to a mountain’s mass.

2) Stellar Black holes — most common and these are approximately 20 times to sun

3) Supermassive Black holes –These are the largest of black holes, more than 1 million times more massive than the Sun.

Black Hole – has two main parts one is the Event Horizon ( peripheral part) and the other is Singularity. ( The central part -Where even light cannot escape it’s gravity ). With the discovery of black holes came the wormholes which maybe the future of time travel or Interstellar travel but warmholes are for another post.

Primordial black hole are interesting because it has the mass of a mountain (thousand million tons) compressed into less than a million millionth of an centimetre, the size of the nucleus of an atom! If you somehow bring it and place it on surface of the earth, there would be no way to stop it from falling through the ground to the center of the earth. It would oscillate through the earth and back making a hole in the earth from top to bottom , and eventually it settled down at the center. that’s the density of a blackhole.

The thick black area is Singularity and that whirling circular area around it is Event Horizon.

All the universe works on principles of quantum physics except near the black hole singularity. Yep! Each and Every law gets broken down near the singularity. It’s gravity is soo strong and massive that even the TIME and SPACE cannot escape and gets trapped at its centre, Imagine how huge the gravitational force it should have to even not allowing light to escape? The fastest thing is itself trapped in it’s gravitation. The one reason It is totally black in the singularity because no amount of light can enter and come back, as The light itself get totally absorbed by the heavy gravity of it, no one knew what will happen at the singularity except the fact that everything get killed and get absorbed in it. If one would imagine himself near the black hole he’ll become like stretched noodles before he could realise.

Ohh NO! Then what about time travel? Well….no one knows it is even possible or not, cuz no one had ever tried ! and all we have is theories.

Before you think someone should try or probably You’ll go try ! I’d like to remind you that the nearest black hole to Earth is “UNICORN” and it is literally “1500 light year’s away” ( a single light year is the time travel by light in a total year ) yes it is that far away! Even if you travel at the speed of light which is impossible, it’ll still take you 1500 years just to get there. Our eyes fool us when estimating distance. Most of the people think stars are close to the earth but actually they are not ! The nearest star to our planet is called “Alpha Centauri” which is literally 4.5 light year’s away. If you stand on it and switch ON a light! It (the light) takes 4.5 years to reach our earth! Even if you use the FASTEST SPACE CRAFT ever built in this world — Parker solar probe to reach the alpha Centauri it would take you 18,000 years to reach there! It’s very near isn’t it !? Do you know? how much time it takes for the light to travel from Sun to earth ? It takes 8minutes — To travel 147 million kilometres. If we use our fastest spacecraft we need 7 years to reach from sun to Earth. Now imagine how far remaining stars and how far a black hole is !🤯

With that said but for the optimists i would like to tell you about the event horizon where the time travel is possible, the event horizon is like the minimum threshold point where the light could barely escape. Normally the light travelling in the space (emitted by stars) passing through a black hole will get completely absorbed by the black hole, and at the point where light barely escapes is not a thin line as one could imagine. it is some hundreds of kilometres wide and if we get there somehow, as shown in sci-fi Interstellar movies we can do time travel to different galaxies and different planets without aging! But passing through the event horizon is next to impossible and it is in only theories. If one can somehow travel quickly fast enough, like a finger crossing the candle through 10,000°Celsius but fast enough to not get burn out you may travel in time ! And change everything you worried about.

Some more facts about star’s

• The brightest star we could see in the sky is called as SIRIUS and it is 8.6 light year’s away
• Most of the stars you see are already dead and due to the distance between it and earth is vast we are seeing it now.
• Stars are shapeless they do not have any shape, it’s because of our atmosphere we see them in star 🌟 shape.
• Stars are more hotter than the sun. Remember Blue is hotter than red.
• You cannot see millions of stars as you think at any time you can only see 2000-2500 stars at a time.
• We are made up of star dust, the hydrogen and helium after the big bang gets cooled down for billions billions and billions of year’s and form carbon and other particles – refer big bang and particle physics for more information.
• Most probably you would have seen a falling Star and made a wish ! Sorry to disappoint you but it is not a star (stars never do that) those are just METEORS – debris or waste material from space entering Earth.