Betelgeuse is the only star that glows red in the night sky. The average lifespan of a star is about 13.5 billion years (1,300 crore). Our sun is around 5.3 billion years old, halfway through its life. Betelgeuse on the other hand is a giant star, much bigger than that of our sun. It has exhausted almost all of its fuel and is nearing the end of its life.
Size Comparison With Our Sun
Our sun is a medium sized star that will turn into a red giant in another 5 billion years ( 500 crore). At that time, as a red giant, it will encompass the orbits of Mercury and Venus. Our earth will be uninhabitable as it will be stripped off its atmosphere and left burnt. Hey don’t worry, this won’t happen even in your great great grandson’s lifetime. The sun will remain a red giant for a million years. In this phase, it will burn its reserve fuel. After a million years, the outer layer of our star will fade away as a gaseous shell, thereby exposing its core. This event is known as a planetary nebula. The exposed core will appear as a glowing white dot known as a white dwarf.
However, Betelgeuse is a massive star which is more than 15 times the mass of our sun. Which means that the mass of the core will collapse and the star will explode into a supernova instead of forming a planetary nebula.
So When Will it Go Supernova?
Betelgeuse is currently a red giant that could go supernova any time. Astronomers are studying the star closely, however, they are not able to determine when it will explode. When it does, the people of earth will experience a breathtaking view of the explosion. The sky will light up and for a brief period it will seem like there are two suns present. The light emitted by the explosion will be so bright that it will engulf a part of the sky.
You may wonder whether we might get destroyed by the explosion. You need not give it a thought as the star is 642 light years away.
Where is it?
On a clear night sky, Betelgeuse will appear as a red star. In fact, it is the only star that appears as a red dot. You can spot it easily as it is a part of the Orion constellation. Refer to the image below.
Did you know that there are more than 200 billion stars in our milky way galaxy? Not just that, it has enough gas to create a few million stars. Every galaxy in our universe is special as it is the home to billions of stars and a few black holes as well. Most galaxies are home to several million earth like planets which are in the habitable zone of their home star. This means that there are over a billion possibilities that we are not the only living beings in the universe.
They come In All Shapes and Sizes
Yes you read it right, all galaxies are not elliptical and boring. They come in varied shapes and sizes. In our observable universe, there are three main types of galaxies which include elliptical, spiral, and irregular. Elliptical galaxies are shaped like a spheroid or an elliptical sphere. On the other hand, spiral galaxies are much spectacular to watch as they appear like a bulged disc with two or more discs which appear like arms. Irregular galaxies have a very haphazard shape and comprise of a lot of star dust and gas.
Our galaxy, the milky way, is a spiral galaxy and we are located at the edge of it. Older stars are clustered at the center of the galaxy and younger ones are spread out. We do not know how many discs our galaxy has because we are inside it and we can’t look at it from a third person view. Neither are we technologically advanced to construct a space probe which can leave our galaxy and take pictures of it.
What’s at Its Center?
The center of our galaxy, the milky way, will appear to remain very bright as there are a cluster of stars present there. According to observations, there is a super massive black hole at the center of our galaxy. This black hole is over four million times the mass of our sun. Scientists theorize that there are super massive black holes at the center of most galaxies. Wheres some speculate that there could be star clusters which are far denser than the ones in nearby irregular galaxies.
How Many Are There In Our Universe?
In the observable universe, there are around 100 billion galaxies. Yes, that is a mammoth number folks. This means that there are several galaxies which are home to harbor life, thereby making it over 1000 billion which are very similar to our earth.
The Milky Way Andromeda Collision
The Andromeda galaxy is a large galaxy which is home to 1 trillion stars, whereas our milky way has only 300 million stars. This is the size difference between these two galaxies.
In about 4 billion years from now, the Andromeda galaxy will collide with our milky way and merge together to form a new galaxy known as Milkdromedia. 3.4 billion years from now, we will be able to view the Andromeda galaxy up close and personal. And trust me, that will be one of the most spectacular sights you could ask for. The collision of these two galaxies will be an absolute spectacle.
Earth day is celebrated all over the world as it is a day to spread environmental awareness about our home planet. It was first celebrated on April 22nd 1970 and has had a word-wide reach ever since. This day is considered to be of great importance as people from different culture, religions, and race come together and spread love. Let us dig into some fun facts about our home planet.
Our Earth Was Once a Barren Hell
About 4.5 billion years ago, just after our sun was formed, there were a set of planets which formed due to space debris that deposited during the aftermath of the star formation. This deposit of debris was the leading cause for the formation of the solar system.
Our Earth is also a product of space debris. It was situated inside a solar protoplanetary disc which posed a hellish atmosphere on earth. The earth was prone to constant volcanic activity which lead to scorching temperatures at its surface. It was like a molten hell with flowing rivers of pipping hot larva. Over the course of the next two billion years, the earth’s atmosphere changed drastically as it was present in the habitable zone of the sun. That is what made life possible for us.
Staying Comfy With Plate Tectonics
Did you know that plate tectonics exist only on earth and not on any other planet. The outer crust of earth comprises of plate tectonics which float on hot magma. They are in constant motion due to the magnetic field of the earth. When these plates rub against each other, they break free from the wrath of the hot magma and resurface. This constant geological activity leads to the formation of mountains, and steep ridges. This is why plate tectonics play an important role in keeping our planet at bay and providing the best scenery which serves as a visual treat.
Is the Earth a Perfect Sphere? Hmm Maybe Not
Hey you may be thinking, yes it isn’t a perfect sphere cause it has mountainous regions and huge canyons. Well the truth is that our earth is flat at the poles and slightly bulged in the region of the equator. It is shaped like an oblate spheroid. The reason why there is a bulge near the equator is due to the rotation of the planet and the effect of the magnetic field.
Molten Iron Core: Our Earth’s Magneto
You need to be ever grateful to the molten iron core which is at the center of our planet which is enclosed by an outer core. This arch angel creates a magnetic field (Magnetosphere) which is powerful enough to encompass our whole planet. This field protects us from the fury of solar winds from the sun. So without the iron core, we would have burned to a crisp years ago.
Earth’s atmosphere extends to a distance of a Whooping 10,000 km
Yes, you read it right, the atmosphere of our home planet is really dense for the first 50 km from the surface and reaches to about 10,000 km into outer space. The layer of atmospheres include the Troposphere, Stratosphere, Mesosphere, Thermosphere, and the Exosphere.
The reason why the density of the atmosphere reduces as you reach outer space is because due to the gravity of the planet. 75% of the Earth’s atmosphere is near the earth. This region is rich in gases like oxygen and nitrogen. The earth’s atmosphere is also our savior as it protects us from small asteroids and space debris by burning them to smothers before they reach the earth’s surface.
Co-orbital satellites: Hey where did they come from?
3753 Cruithne and 2002 AA29 are two asteroids which are locked into a co-orbit with earth. These two spacefarers orbit our sun in a synchronized manner. The image below will give you a better perspective.
Understanding space time is the key to learn everything we know of our universe. Albert Einstein’s theory of relativity digs deeper into space time as it gives us a perspective about time dilation, speed of light, theory of general relativity, and the laws of physics.
Space and time were created during the big bang. When the universe was young, just after the big bang, space time was just a tiny bubble. Just after the big explosion, there was an instant inflation which forced the universe to expand. The universe is currently expanding at a rapid rate. Scientists believe that the expansion of the universe is so fast that it could easily surpass the speed of light. This is also known as space-time inflation.
This sudden expansion of the universe is something which has baffled astrophysicists. The expansion of space-time occurred about 10-23 seconds after the big bang. This happened so instantly that the speed of the expansion remains unknown till date. The laws of physics state that, no object of mass can move through the universe at the speed of light. However, the inflation of space itself doesn’t contradict the law as space doesn’t have mass.
So What is it About Einstein’s Theory of Relativity?
Einstein’s theory of general relativity discusses about the curvature of space-time. It clearly describes the geometry of space. Before Einstein, we believed that the universe obeyed Euclidean geometry. Which states that in the universe, parallel lines do not intersect and the sum of the angles of a triangle is 180 degrees. This means that we perceived the universe to be a single plane of existence where space and time cannot be bent or traversed.
However, this is not the case. As a Euclidean universe would only comprise of static objects of same mass. Albert Einstein’s theory states that the universe follows non-euclidean geometry where the angles don’t sum to 180 degrees and parallel lines can cross, intersect or diverge.
Picture the universe as a piece of paper or cloth. Let’s say that you place an object of considerable mas on it. When you do so, the piece of cloth or paper will bend to support the mass of the object. Well! This is how space-time works. Gravity plays a vital role in this aspect as it is responsible to bend space and time. Without gravity, objects remain static and space time cannot curve. Space-time can bend, wrap, or curve depending on the matter inside and the force of gravity acting on it.
The faster you go, the slower time appears to you. This is a simple explanation for time dilation.
Let’s say you embark on a journey to a nearby star which is about 2.5 light years away from the earth. Picture yourself traveling in a spacecraft at 50% the speed of light. You will reach the star in about five years. You carry our the mission and return back to earth. Now, the total time passed from your perspective will be 10 years. Well! Here’s the twist. When you reach earth, you will notice that more than 15 years have passed. In your time, you would have traveled so fast that the time on earth would appear to move slow. However, in reality, the time on earth will move at its normal pace. The crux of time dilation is that the faster you move through space, the slower your move through time. Therefore, you would appear to be younger than the people on earth.
This topic of discussion is solely a product of science fiction. With current technology, we cannot find a possible way to manipulate space-time. However, a time may come, where we could develop to an extent that time manipulation becomes child’s play. Here are some ways to do it.
Time Machine- With a time machine, you can travel to the past, present, or future. This gives you complete control of time. According to science, you can only travel to the future and not to the past. As traveling to the past would require you to spin the earth anticlockwise, which is an impossible feat.
Traveling faster than the speed of light- This theory boils down to the creation of the universe. The big bang led to the expansion of space and time way beyond the speed of light. If we could figure out how to create another big bang, we could easily manipulate, space, time, and matter.
Wormholes- Wormholes can provide a passage through space-time. But don’t get all high as we are yet to discover them. If so, we can travel through various planes of existence and perhaps visit other galaxies or maybe even a parallel universe.
What is the first thing that comes to your mind when you think of black holes? You may be thinking, all right, they are giant holes in space which can devour planets. Well you are right, but what if I told you that black holes are far more powerful than you can imagine. Read on to know more about these amazing extra terrestrial vacuum cleaners.
Stars have a lifespan of about 10 billion years (1000 crore years). Once they reach the end of their lifespan, they will turn into a red giant and burn on reserve fuel. For medium sized stars such as our sun, the end of this phase will result in the formation of a planetary nebula which results in the formation of a white dwarf. However, in the case of stars which are more than 15 times the mass of our sun, they will collapse under their own gravity thereby causing a massive explosion. This explosion is known as a supernova. During the explosion, a rip in space time will occur thereby creating a hole. Only if a star which is 25 times the mass of our sun goes supernova, a black hole will form, as smaller explosions do not contain enough energy to damage space time.
Once the black hole is formed, every planet within its vicinity will be sucked into it. It is like a devastating whirlpool. Black holes are so powerful that even light cannot escape it. This is the reason why black holes are so dark.
There have been numerous photos of black holes which are just artist impressions. However, on April 10 2019, a group of scientists at Event Horizon Telescope Observatory have captured the first ever image of a black hole. This is truly a remarkable achievement for humanity.
Even Horizon: What’s on The Other Side?
The event horizon is a point after which light cannot reach our eyes. Since black holes are so powerful that even light cannot escape them, you simply cannot see the what is on the other side. Picture a spacecraft falling into a black hole. The moment it crosses the event horizon, the spacecraft will appear to remain in free fall. However, in reality, the object would have already got sucked into the hole faster than the speed of light, thereby leaving an image of its last location. Yes, this is no optical illusion, its science.
When there is a rip or damage in space time, a singularity occurs. Picture an area of space where there is no gravity, no light, and that the laws of physics do not work. Yes you guessed it, this is a singularity. What happens when you divide a number with zero? The answer is infinite or indefinite right. This is the mathematical explanation for a singularity.
Does Nothing Really Escape it?
So, you may be wondering, if black holes are so powerful then nothing could really escape it right. Hmm, you are partially correct. No object of considerable mass can escape it, however, some amount of radiation can escape it.
At the event horizon, the black hole will capture one pair of particle-antiparticle matter. This causes an electromagnetic radiation which leaves the vicinity of a black hole. This electromagnetic radiation is known as Hawking radiation as it was the theoretical physicist Stephen Hawking who came up with this amazing theory.
Myths About Black Holes
There are several myths about black holes that are derived from science fiction movies. Here are some common myths.
Myth 1: The volume of a black hole is huge.
Fact: Black holes have varied mass, they are classified as small, massive and supermassive.
Myth 2: If you get sucked into a black hole you will travel to another dimension.
Fact: You seem to be strongly influenced by the movie interstellar. In reality, a black hole can literally vaporize a star which has a far greater mass than the sun even before it reaches the event horizon. So, just imagine what it could do to your body. Moreover, black holes do not lead to wormholes. Wormholes exist in theory but are not proven.
Myth 3: Our sun will eventually become a black hole.
Fact: Our sun does not have sufficient mass to go supernova let alone create a singularity.
Bucker up! lets take a journey into the future and see how high we can rise as humanity.
We as humans, have the capability of doing the impossible. Just read on to know how well we can adapt to change and develop as a civilization.
World peace is the first step to develop as a civilization. We need to look out for each other, destroy corruption, and spend our resources wisely. This will help us reach great heights. If everything goes as planned, we can strengthen broken bonds and evolve as humanity.
By the year 2070, we will remain independent of fossil fuels. We would have come up with alternate fuels such as electricity, solar, or nuclear power.
We can gain control over nature. For instance, we can control the tides by using advanced oceanic equipment. Thereby prevent tsunamis. Highly advanced weather trigger systems can help us control the movement of earth’s plates by preventing earthquakes and volcanic activity.
Better yet, we can trigger a natural disaster and create shields which are powerful enough to filter UV rays and small asteroids. We will never be dependent on one source of energy and will have access to many. Large solar panels could be built to extract sun light that reaches the earth. In this manner, we will never be deprived of energy. Theoretical physicist Michio Kaku speculates that we will become a planetary civilization by the year 2100.
Stellar refers to Star. This civilization will be capable of extracting all the energy from its parent star, in our case, its the sun. It will take a lot of time and technological aid to reach this level.
A Stellar civilization can build a Dyson Sphere around its parent star and extract the energy emitted from it. A Dyson sphere is a huge sphere which encompasses the sun. The inner side of the sphere contains a lot of solar extractors which are similar to solar panels. This sphere will be linked to a nearby planet which can store energy in strong equipment that is powerful enough to contain this energy. The concept of a Dyson sphere was proposed by Freeman Dyson, a British-American Theoretical physicist.
The energy extracted by the sphere can be combined with uranium to create powerful fuel. We can construct rockets which run on this newly created fuel. The speed of this rocket will be powerful enough to propel you at 50% the speed of light. In this manner, we can travel to nearby stars. (interstellar travel)
A stellar civilization can colonize itself in other planets, form an interplanetary constitution, and form laws which are common to a whole planet.
This type of civilization can avoid a major meteor collision by altering the magnetic field of its home planet by using advanced gravity inducing electromagnets. It can also construct powerful weapons which are capable of destroying a whole planet in a single strike.
A stellar civilization can control the orbit of other planets. It is considered to be a virtually indestructible civilization which can only be destroyed if a supernova explodes or a civilization more advanced than theirs attacks them.
This civilization can control every planet in its vicinity, mine extraterrestrial minerals, and use them effectively. Scientists say that We can reach this level by the year 4,500 or 5,000 AD. It may also be sooner or later depending on how fast we evolve.
A galactic civilization can control the entire energy of its host galaxy, in our case, its the milky way.
At this point, humans would have evolved to such an extent that our brains cells would have increased to over a million folds. We will be able to adapt to change and calculate faster than a super computer. Our bodies will have the ability to change its orientation to adapt to new planets.
A galactic civilization will make interstellar travel seem like child’s play. It can literally colonize the entire galaxy and extract energy from multiple stars and planets. This civilization can deconstruct planets and reassemble them in at different location. They can also perform star lifting, which is the act of moving a whole star to any desired location by using advance equipment.
Black holes can be used as a prime energy source. Solar systems or a cluster of stars can form an allegiance and run as a governing body. A galactic civilization would have control over most matter that exist within its reach. These include starlight, gas, and minerals. They would have constructed large space habitats which can be a home to many. We can reach this level at around one billion years (100 crore years).
An intergalactic civilization will have the ability to extract energy from various other nearby galaxies. This civilization would be capable to freely manipulate space-time, create black holes, neutralize supernova explosions, and perform other unimaginable feats. In this day and age, we cannot possibly think of the feats that this civilization can do.
If we set aside our differences and work as humanity, we can reach great heights, break boundaries, and achieve the impossible. This blog is inspired by the idea of the Kardeshev scale proposed by Nikolai Kardeshev, a Russian astrophysicist.