Stone's on Fire

        Fireballs with a long tail that passes the night sky has always been an wonderful sight to watch. During ancient , many myths were put upon in much more fascinating way about them. According to them, it even marked the beginning or the end of an civilization or kingdom and many more. Dawn and Dust - just with a click in the mind. Frame a story out of imagination whenever these glamorous fireballs pass by. Make people believe it. That's it! Mission accomplished !

Comet Representation
Photo Credit: Firstpost

    As time passed and various technologies grew and developed, physicists and scientists can now explain what these objects are and do these objects have the potential in them to reveal or fore tell the fate of a kingdom that's on Earth just by passing through the sky?

    Let's go find out!

    Kupier Belt and Oort cloud , are the place where icy objects made of frozen water and carbon-dust , in frozen form, are present. We saw about these in the previous post. These frozen objects, when its motion is disturbed by some massive star near it., somehow sends them into the inner Solar system, the region comprising Sun and its  Eight known planets. Their orbit has been changed. They now orbit Sun or whatever massive Planets that comes in their way. For now, let's just focus on the Sun.

    The frozen object, orbiting the Sun, when it comes closer to it, the heat of the Sun sublimes the icy dust it is made of. The object in this particular stage/phase is called comet! The comet has a nuclei where most of it is ice and carbon dust. It is the central part. The heat of the Sun, as I said earlier sublimes it. To bring in an analogy, it is similar to the camphor burning at pooja rooms, where the heat converts the camphor from solid directly into gas. The same happens in the comets too. The heat gives out gas and produces an atmosphere around the nuclei - it's called the coma. The solar wind pushes the dust and gas particles away forming long tails. Not just one but two tails - like the naughty children - one spewing out ionized gas and the other dust particles. Finally, a gorgeous sight for us to look into!

Inside of a comet 
Photo Credit: Encyclopedia Britannica 

    The tails of a comet can go for about millions of kilometers. The sparking of the tails is due to the reflection of light on it. The comets go around the Sun in big orbital length, when they reach the nearest side of it, they give out gases and if they do not completely die off, they go on in their orbits again. There are two categories - Short period comets which takes less than 200 years to orbit the Sun and Long period comets which takes more than 200 years to even millions to orbit the Sun!

    The repetition of the same pattern over and over gives rise to period. We may have heard about the comet Halley which takes 76 years to orbit the Sun and upon every 76th year if the comet has not been influenced by any other massive planet or if its material remains without being wiped out completely, we would keep observing it when the time approaches. 

    So, to end , the fireballs has got nothing to do with the happenings of the Earth or in determining the fate of an individual. If you happen to see a comet, enjoy observing it and don't think what it has to do with your past, present or future.

    So, until next time, bye! bye! 

The Left-Outs

                       It's so cold out there. So cold that everything's frozen. Dark and Wild. Carefree and Leisurely.  Icy and freezy. Not much sunlight left to light the space but quite an amount of gravity's left to attract and make things go around it. Things are slow. It takes about millions of years for the objects to go around the Sun once. As there's not much gravity, they don't clump together to form big planets. They are small and only range from few kilometers to few million kilometers wide. You could not expect a perfect shape from them. They are in whatever shape they like. Maybe, we can say. they are the making of their own! 

               Out there, there are more number of objects in millions or trillions- small asteroids to small planets - we are not sure about it. If you start your journey from the Sun to about a distance of  about 4.5 billion kilometers, you would reach the region after Neptune - the last known planet in our Solar System surrounded by many such objects in the shape of a donut - it's called the Kupier Belt and the objects are made of mostly ice and dust. It's in form of the a ring surrounding Neptune. Even Pluto belongs to this region but it's not a planet anymore. So let's leave it aside for some time.

Kupier Belt 
Photo Credit: NASA

           Even more far away, beyond the Kupier Belt, there is a region called Oort Cloud. To explain how it is, let me bring an analogy here. Our Earth is surrounded by so many satellites sent by us for our own use. They leave out a lot of debris when affected by sun's radiation and cosmic rays. They form up a shell around the Earth due to it's gravity. Likewise, there is a region out there, that is if you begin now, approximately after three years, if you travel in the speed of light, you would reach that region and could be able to witness it yourself. A region that is like the shell of our Solar system composed of debris that might be the remains of the formation of the Solar System. 

             

Oort Cloud
Photo Credit: abyss.uoregon.edu

                The existence of the Oort Cloud is still theoretical and unproven but they are believed to be the source of most fascinating object that we see during the night time, glowing and spewing out a lot of gas on the sky. What is the fascinating object and to know more on it, stay tuned for next update. 
          

              

          

Back Back Back

             What about some time travel? 

              It's about time to set our clocks ready. Let's set it back. Set it back to about 4.6 billions years in the past. Time is set, tighten the belts and sit comfy. Woohoo!  We are travelling through time. Don't ask if it will take a lot of time or if would be boring? Just enjoy the moment and let me wake you when you reach the destination. A destination - not the one which changes from place to place but which changes from time to time. It's not gonna take much time.  Anyways, there is more to wonder. So, off you go to sleep and rest for a while.

            Wake up sleepy eyes! We have reached. What do you see around you? Omg, where is the sun, man ?! Where are we even standing ? Where are the rocky planets - the Mercury, the Venus, our home planet Earth and our gonna-be living planet Mars and the big giant Jupiter, the ringy Saturn and the icy Uranus and Neptune? Have they disappeared ? Where the heck are their moons and why are we surrounded by dusty clouds? Hmm, it looks beautiful although it's like being in a world of clouds!!

                 Of-course, we would be wondering like this if we go back to the time before the birth of our Solar System. We are now at the outskirts of our Milky way galaxy, at the time when our Solar system is yet to be formed. It began with the gas and dust clouds called the Solar Nebula, which mostly contains matter in gaseous form. The matter may consist of atoms or ions ranging from hydrogen, helium to higher atomic numbered atoms. The kind and vastness of the particles just depends on the star that has previously died out. The nebula is as a result of a death of a big star. - to be precise - let's say it's actually the remains of a star which has ran out of fuel in its tummy and has died out eventually, by a big explosion. They have a name for this explosion too - its Supernova! 

                  The matter in these gas clouds are in continuous and random collisions with each other, eventually producing heat and they start to clump together due to their own gravity. When matters clump together, there is more mass and which means more gravity too! The more gravity it gives out the more and more matter comes together and they began to get bigger in size. If the matter mostly consists of hydrogen, then it goes on to become a star -  a thermal (nuclear) engine has been born! 

                This engine has more gravity. It attracts other minor bodies that are around, in small chunks and makes them orbit around it. The minor chunks, when they orbit the star, began to take shape. It takes a lot of years to finally cool down to a definite shape - although it always changes. They finally result as planets if they are made of higher atomic materials, if their radius is just enough to become a spherical body. The heat and radiation from the Sun does not spread out to an infinite distance. So the objects near it are heated and melted and only the matter which withstands that much heat can survive which is mostly metals and that's the reason the planets, nearest to it are solid and rocky like the four planets near it and the planets quite far away are gaseous and big like the four planets beyond Mars in our Solar System.

 What's beyond these planets? 

                 To find , stay in touch and wait for the next unravel!

  Until then , bye bye!

                                     

OCTILLION WATT BULBS ON SKY

     Our home planet Earth we live on is stationed at the " not too hot- not too cold-just right" zone around the Sun, which among the Astronomers is known with an alluring term - the Goldilocks Zone. It just means that it is the exact position for the life on planets to begin, evolve and thrive. 

    The Solar System(The Sun and its Eight Planets), we belong to, is cornered at one of the arms of the galaxy called the Milky Way. Our Sun is not the only star here and our neighbouring planets not the only planets around here. There are just billions of stars, bigger or smaller than our Sun, going around a Black hole positioned at the centre of our Milky Way, just enormous amount of it in our Galaxy alone! How enormous is it? To add, there are trillions of galaxies and in each, billions of stars. How do you term enormous now? Doesn't it seem miniscule? 

    Stars are a source of great deal of energy giving out huge amount of light every now and then. The light that it gives start their voyage and goes on and on. The time it takes to reach us depends on it's distance from us. For example, the Sun's light takes us only few minutes to reach us but the stars that are far away takes some time even more to reach our sky and if the Sun dies out, we would know it in few minutes (Not instantly but only after 8 minutes) but what about the stars that are far away? It takes a lot of time for us to know. If you are looking now at the sky, for what you think is present, you are actually looking into the past! 

    The stars we look at, twinkling in the night sky as tiny dots, lit on and off like the chain of LED light bulbs that beautify the streets and trees on Thiruvila days, are actually far away, so far away that their light once given out years or even eons ago, reach us only now.. The reason the stars looks as tiny dots owes to its distance and its twinkling nature has to do with our Atmosphere. Our Atmosphere is a  vast region around the planet containing many layers with different temperature and lumps of atoms of different densities bending the starlight as much as it needs and making it appear as tiny bulbs going on and off, thus achieving the status of concealing the power of the octillion watt bulbs on sky.

    So next time someone asks you, do the stars twinkle, just say, "They don't. It is the atmosphere that make them twinkle".

To be continued...

Until then, tschüss from 

Brundha 

    

The Blue Wrapping

     This is a story of a Mighty Father and his capricious children. A father not with limbs like terrestrial beings but with a ball shaped body. White hot glowing body at the centre of our Solar System. He is mighty and with mission. He cares deep for his children, like Thanos, a mission-a-holic daddy. He gives birth to enormous children at his core. The stillborn babies have a lot of energy contained in them as gamma rays. For over thousands of years, the belly of their father is their home and playground. It is playtime always. They have a lot of time to play. (Wish we had too!) They cherish and spend time with each other, giggling and smashing into each other, not worrying of the energy they lose during their mega-annum play. The lovable daddy treats all his children in the same manner so is his unique style of calling everyone by the same name - Photon.

     After spending hundred thousand years under his warmth and guardianship, he assigns a task to all his children who have been playing all while and who has started their play from his innermost belly to the surface of his belly. Now they are youths and has shredded their energy from  X-ray to Ultra-Violet. Some stay as X-rays. Few as Ultra-violet. Their playtime is over and they are free to travel anywhere. He sends out his young ones as messengers in all directions. They have a strength. They can travel with the speed of light.(Wait a second. They are the light!). In a second they can travel three lakh kilometers. (So if a young teen befriends a girl Photon and while he is snapping his finger she will be gone three lakh kilometers away. Gone! Gone far away. Can he catch her? Actually he can. Yes, with his eyes)

     The Photons are so excited like the school children are on the day of their picnic. Keeping in mind the task their daddy gave them, they start their journey. They do not have to cross huge mountains and valleys like on Earth. They have a stupendous void space before them to trek. Wherever they look it's just empty space. Oh! Lonely little ones. Not dropping their hope, they keep travelling. They come across few spherical balls, what we call as planets, during the voyage . After a struggle of eight minutes and twenty seconds they see a blue ball called Earth floating in the vast space. They are tired and has lost some energy on their travel. What's waiting for them on the blue ball?

    The blue ball has a great defence system. Locals of the blue ball call it - the Atmosphere. A defence system with that much potential is found only in that blue ball. That's the peculiarity of it. The soldiers of this defence system are not mighty like the big daddy - The Sun. The soldiers are so small and escape the vigilance of our naked eyes. They are ominous but invisible. There are trillions and trillions of them stationed around the blue ball. Locals have a name for them too.  It is "the Atoms". But here, they are all not alike- most of them are called Nitrogen. Some as Oxygen and few others by many names which I don't remember properly but they exist too.

    The defence system has five major units – The Exosphere, the outermost unit, then the Thermosphere, followed by the Mesosphere – the middle one, after it comes the Stratosphere and finally the lowermost unit – the Troposphere. The Exosphere, the defence unit which is above 1000 kilometres from the ground of blue ball and where the space station ISS orbit - it is cold and hot out there– an oxymoron situation. There’s no big struggle. So, the incoming Photons are free to enter the Thermosphere. The soldiers in the Thermosphere welcome the Photons in exchange of few Ultra-violet energies, which is the source of energy for these soldiers to get ionized. After the trade, they send them in to deal with the next unit. The soldiers are stationed in large numbers in the below three units. The Photons are scattered by these soldiers in all the directions. They are naturally white in colour – containing the seven colours inside them – Violet, Indigo, Blue, Green, Yellow, Orange and Red. The colour Violet has more energy and can only travel few distance (low wavelength) if scattered and as we go from Violet to Red, the energy depletes but their travelling length (wavelength) increases. The soldiers aim at the Photons and scatter them in all the directions. The Blue colour which can travel only for a tiny range is scattered more in the nearby regions since they are easy to catch. All these scattered Photons reach the back of inside of  the eye – the Retina and hence the sky appears blue for the terrestrial beings at the middle of the day and hence the Sun – their daddy looks white in the midday. (Don’t look at it directly). 

    Those Photons scattered away by the soldiers resume their journey and go in straight lines unless disturbed. We may not know what will happen to them on their way but eventually they will lose their energy and die out , before that they have served their purpose throughout their way – giving light in the darkness. The messengers of light! 

To be continued...

Stay tuned for more Unravels!

The Minor Questions that matter

Don't tell me the sky is the limit when there are footprints on the moon - Paul Brandt 

Have you ever wondered what's beyond the blue wrapping of the sky ? Is it really a wrapping ? The colour of the wrapping - blue - is it really blue or is it blue only to our eyes ? The twinkling stars that dance during the nighttime - do they really twinkle? How happy were we when the fair lady somewhere on the blue wrapping followed us back as we ran and those childish moments where we shouted with awe, with those tiny teeth (toothless, actually) not knowing the real reason behind it.  

The fireballs with a long tail that came racing and suffocating to somehow reach the surface of the Earth before its dies out burning itself to death. Do you know? They were actually stones - quite big - floating in the space some where high above the blue wrapping but as it came below the wrapping it caught fire. Stone's on fire, hah? So why does it catch fire and sacrifice itself before reaching down? Is it some mystical force or is there some science behind it?

The creator and sustainer of life on Earth - the Sun (as portrayed in many religions). Is it a GOD or actually a star? As we ask, a question arises, what's a star and  how is it made ? Can we make a star? 

A warm and welcoming home - the Earth , a big sphere( not a perfect sphere) that floats with certain speed around the Sun. (What , are we floating1?) What path does it follow- is it circular or more like around the egg .(Around the egg in 365 days ) We know that Earth's a planet and there are eight known planets (Bye Bye Pluto) in our Solar System. So, what is it and what's beyond the our Solar System? Where are we and what's our actually address? How aged are we and what are we really made of ? 

Oh, now a lot of questions arise colliding with each other like the atoms in the hot zone but how we be is like a tortoise and unravel the questions one by one and find answers to it in the coming days. We have lot time, do we?

Stay tuned to not miss a single unraveling and to have a great fun during the journey. 

Post your comments below.

With the quest to unravel,

Brundha K