The Places Where God Divided By 0 - Black Holes - 2

June 28, 2020

By: Haris Ahmad[1]

In my last blog, I explained the types of black holes and how they are formed. In this blog, I’ll explain the general structure of these monsters wandering in the dark. These mysterious objects are one of the greatest mysteries in the universe. Even though we don’t have in detail knowledge about these monsters, we still know about them to some extent through mathematics and theories. Though, the image taken in 2019 made it somewhat clearer.

In case you didn’t read my previous blog, you should go and read it because if you haven’t, you won’t understand a lot. As I explained in my previous blog, black holes are regions in space where the gravitational field is so strong that not even light can escape from them.

The boundary of the black region of a black hole is called the ‘event horizon’. This is a point of no return.

https://en.wikipedia.org/wiki/Gravitational_singularity

This means that once something goes into it, it can't come out. What exists beyond this point is not known to us. Whatever object goes near to this point is attracted by the black hole into a point of singularity. The point on singularity is an infinitely small and infinitely dense point. This is the reason why I named this blog, the places where God divided by zero because the formula to find density is p= m/V, where p is the density, m is the mass and V is the volume. Since a black hole has zero volume, the mass is divided by zero and hence the name came into my mind.

Moreover, the point of singularity is extremely mind-boggling since this is the place where the laws of physics no longer apply. Finding these monsters is a great deal for scientists since they are invisible and can only be seen when they feed on nearby matter.

https://astronomynow.com/2019/10/13/best-view-yet-of-flickering-jets-in-black-hole-feeding-frenzy/

This means that there could be a black hole anywhere around us, waiting to suck us all in. Just in the milky way, there are millions of these monsters.

Scientists study black holes’ behavior when they see their effects on the nearby matter that it eats in. Therefore, when a black hole feeds on the matter, it forms an accretion disk, which is a disk formed by the dust and gases that fall into the gravitational field of the black holes.

Did you know that anything in the universe could become a black hole? In 1916, Schwarzschild, who was a German physicist used Einstein’s general law of relativity to calculate that any mass can become a black hole if it is compressed to a limit called the Schwarzschild radius.

In 1971, the great theory of black holes became reality when Astronomers studying the constellation Cygnus discovered the first black hole.

There are incalculable numbers of black holes in the universe that are constantly stretching the fabric of space-time to unimaginable limits. If only one comes a bit close to our Solar System, we will all are doomed.

The Places Where God Divided By 0 - Black Holes - 1

June 21, 2020

By: Haris Ahmad[1]

We live in a universe that is boundless and is impossible for us to wholly understand or completely see. This is not only because it is so large but, also because it is expanding at ever-increasing rates. Therefore, we are only limited to see the part of the universe which we call the observable universe. According to current estimates, the observable universe is about 93 billion light-years across.

The universe is home to countless types of celestial bodies among which, some are just too complex for our tiny brains to understand. The common celestial bodies that exist are planets, stars, galaxies, nebulae, etc. However, that is not it. Among the universe, exists a monstrous celestial body of whom, the gravitational field is so strong that nothing, not even light (the fastest traveling entity) can escape the grasp of these monsters.

Many of you may have prior knowledge about black holes because they are all over the internet. You will find thousands of videos on what black holes are, how do they form, where do they form. Therefore, in this blog, I will briefly explain what these monsters are.

I will come to the explanation of my title later on but for now, let's start with what these are and how do they form. Black holes are regions in space where gravity is so strong that nothing, not even light can escape its grasp. 

https://en.wikipedia.org/wiki/Black_hole

These monsters are all over the universe. In fact, We have one humongous black hole at the center of our galaxy too. Besides, there are millions of smaller black holes wandering about in our galaxy.

The idea of black holes were first proposed by a geologist named John Mitchell in 1783. These objects were referred to as dark stars that were so compressed and dense that the escape velocity from these objects was faster than light. He also gave evidence of how these objects could be found in space. He explained that if you were to find a star system with two stars in which the only one was visible, the second object with the star surely is a black hole. However, this idea was rejected and forgotten for two centuries since it seemed so illogical and impossible back then.

Moreover, let's explain how black holes are born. Before this, however, we need to know that there are three types of black holes, primordial, stellar and supermassive, and each of these forms in their own ways. The first and smallest type is primordial black holes. These can be as small as a mountain but can still possess the mass of a mountain. These were formed soon after the big bang when radiation dominated the universe.

Furthermore, the next type of black holes which are larger than primordial ones is stellar black holes. 

https://www.express.co.uk/news/science/1161693/Black-hole-shock-millions-of-hidden-black-holes-draining-Milky-Way-galaxy

A 10-mile stellar black hole can possess a mass almost 20 times larger than our Sun. These black holes are formed when a massive star collapses onto itself after it runs out of fuel at the end of its life in a supernova explosion. This explosion can either give birth to either a white dwarf, neutron star, quark star depending on its mass. However, if the mass surpasses a limit called the Tolman-Oppenheimer-Volkoff. It will collapse until a stellar black hole is formed.

Lastly, there exist supermassive black holes that can possess the mass of millions or even billions of Suns.

https://solarsystem.nasa.gov/news/1068/10-questions-you-might-have-about-black-holes/

These types of black holes can be found at the center of galaxies. In fact, a supermassive black hole known as Sagittarius A* is located at the center of our Milky Way galaxy. It is commonly known that these types of black holes start small but end up becoming humongous monsters. However, it isn’t really clear how these black holes came into being in the first place. One theory suggests that they either formed due to the merging of many clusters of black holes that collided together and another one suggests that they formed in the early universe when large clouds of gasses collided together.

This was the end of the first blog of this series. I will explain more about black holes in my next blog of the series.

Pulsars - My Favorite Celestial Objects

June 14, 2020 

By: Haris Ahmad[1]

Our universe is a boundless place that is impossible for our brains to wholly understand or for our eyes to completely see. This is not only because it is so large but, also because it is expanding at ever-increasing rates. Therefore, we are only limited to see the part of the universe which we call the observable universe. According to current estimates, the observable universe is about 93 billion light-years across.

This enormous size means that if any event takes place at one side of the observable universe, the light from that event would take 93 billion years to reach to the other side for any extraterrestrial intelligent life to see. However, that’s not all. The universe is much bigger than that. The observable universe is so tiny in comparison to the whole universe that, it is as if you place a light bulb in the middle of the dwarf planet Pluto (2300 km in diameter). 

You see, the whole explanation I just gave was to give you an idea of how enormous the universe is. Therefore, it is home to unimaginable types and numbers of celestial objects. Among these, the most common to us are planets, stars, moons, asteroids, black holes, etc. However, among this vacuum exists many other types of celestial objects that are extremely fascinating. 

Hence, in this blog, I will explain my favorite type of celestial objects that many of you may not know about. These celestial objects are known as Pulsars. These objects are neutron stars and are the densest in the universe. One spoon of Pulsar mass is equal to the mass of Mount Everest.

https://www.nasa.gov/feature/goddard/2017/nasa-continues-to-study-pulsars-50-years-after-their-chance-discovery/

A 12-mile pulsar can weigh as much as 1.5x our Sun which is 1392680 km large. Moreover, these objects mostly exist in the most beautiful places in the universe, those places are, Supernovas.

https://en.wikipedia.org/wiki/Supernova

Pulsars are rapidly rotating neutron stars that emit pulses of radio waves and electromagnetic radiation at the rates of up to one thousand pulses per second. The speed of the spinning of these monsters is just mindboggling. For example, the sun spins at a speed of 1.997 km/s while Pulsars spin at the speed of 70,000 km/s. 

Now, let's talk about how these monsters are born. If you have read my Solar System related blogs, you may know that stars like our own Sun produce energy using a process called thermonuclear fusion. This means that it fuses two nuclei to produce a larger single nucleus and the main fuel for this process is Hydrogen and Helium. Therefore, one day the fuel has to end and when a star 4 to 8 times the mass of our Sun comes to the end of its life and runs low on fuel, it can no longer fight back against the gravity from its core and collapses, producing an explosion to become a Supernova (A luminous stellar explosion). This explosion is so strong that the whole shell of the Star is completely blown into pieces and the Protons and Electrons in the core fuse together due to the influence of immense gravitational forces. Therefore, the star ends up becoming a tightly packed ball of neutrons and becomes a neutron star. Over time, this ball of neutrons gets compressed more and more and starts spinning faster and faster. Physics calls this process, ‘The Conservation of Angular Momentum’. The outcome of this process is a neutron star that spins as fast as hundreds of times per second and this star is arguably the smoothest object in the universe too because the gravity aligns the neutrons together in a smooth sphericle shape. This neutron star now has so much mass and energy, that it starts shooting jets of energetic particles from its poles and there you have it, a Pulsar. 

For years, scientists were muddled as to what is this object was, emitting light in the form for X-rays and blinking in constant intervals. However, after decades of deep research, they found out that they were the beams of light emitted by neutron stars that pointed straight towards Earth in constant intervals. This was just like a lighthouse’s beam that you can see passing in front of you. 

Furthermore, just like any other object in the universe, Pulsars, and other neutron stars also come to an end at some point in their life. They gradually slow down until they stop spinning and wander in the vacuum of space and lie undetectable to our technology. From the time of their discovery, we have successfully detected approx. 2000 pulsars and will continue to discover more.   

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[1] Haris Ahmad is currently studying in 9^th grade (O levels) in The City School Islamabad.

The Closest Star to Us – Explanation for a Newbie

June 7, 2020

By: Haris Ahmad[1]

In my previous few blogs, I explained the whole Solar System in simple words so that people having very little or no knowledge about the Universe. We covered all the aspects of the Solar System except asteroids because I have already explained them in detail in one of my blogs in the past. For now, we are taking on a relentless journey into the unknown to understand how everything in the universe works.

In this blog, I will explain about the closest star to us beyond the Sun. The name of this star is Proxima Centauri. It is also known as Alpha Centauri C because it is a part of the three-star system called the Alpha Centauri star system. Proxima Centauri is about 4.2 light-years away from us.

https://www.quora.com/If-our-sun-is-a-star-then-why-do-we-say-that-the-star-nearest-the-Earth-is-Alpha-Centauri

This might seem like a tiny number but in terms of space travel, it is a humongous number. Before taking in detail about Proxima Centauri, I’ll explain Alpha Centauri A and B. Alpha Centauri A is a star which is very similar to our very own Sun in nearly all aspects. On the other hand, Alpha Centauri B is slightly smaller and dimmer than the Sun. However, it is still quite similar to our Sun. Proxima Centauri is a much smaller star that is categorized as a red dwarf star. Furthermore, Alpha Centauri A is very promising for life because the bombardment through solar flares and radiation is very low on this star. Moreover, on Alpha Centauri B conditions for life are slightly hostile. Lastly, Proxima Centauri is extremely hostile to life because it is a type of active red dwarf star which bombards its surroundings with dangerous radiations. Hence, the best place for life to evolve in this star system is in the goldilocks zone of the star Alpha Centauri A. The goldilocks zone is a region around a star where conditions aren’t too hot for water to boil nor too cold for it to freeze. Therefore, it is a region where water can stay liquid. Even though Proxima Centauri is very hostile to life, there is a planet named Proxima Centauri b which orbits it in its goldilocks zone. Hence, many theories of life have arisen on this planet. This planet is slightly more massive and larger than our planet Earth. Even though this planet orbits its star closer than Mercury orbits the Sun, the planet still haws a temperate climate. This is because Proxima Centauri is a very small red dwarf as I explain before. Though this planet may have chances to harbor life; deep research shows that this planet isn’t the place to look for life and there are various reasons for this. Firstly, planets that orbit their stars at such a close distance are tidally locked. This means that this planet may be tidally locked which means that one side of the planet faces its star while the other faces away. This suggests that one side of the planet will be burning hot while the other will be cold. Now that isn’t the place to find life, isn’t it? However, heat distribution done by the atmosphere of the planet may even out the differences but, who knows? Furthermore, another reason for the planet’s habitability is one that I explained earlier. As I explained, Proxima Centauri is a red dwarf, that is a type of star which is ridiculously active in terms of ejecting radiation and experiencing solar flares.

https://phys.org/news/2018-04-proxima-centauri-flare-powerful-visible.html

The ozone layer of the planet may be bombarded to such an extent that it might have just been blasted away. Therefore, exposing the surface of the planet to harmful radiations of the parent star. However, if this planets’ magnetic field is strong enough, it may shield itself from these calamities.

This was the end of this blog, in my next blog, I will explain another aspect of the universe in simple words for newbies to understand easily.

[1] Haris Ahmad is currently studying in 9^th grade (O levels) in The City School Islamabad.