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Unfolding the Mysteries of the Universe- Knowing more about Black holes

The mysteries of the universe have always fascinated me. Even as a toddler, I would look at the night sky and wonder "What is out there"? I was always curious to know
more about the Universe. When I grew up, I understood that we are nothing but a speck in the vast Universe. The universe is so large that our mind can't possibly
comprehend it. Out of the many objects in the universe, the one that intrigued me the most were the Black holes. Black holes are formed when a massive star, at least
having ten to fifteen solar masses, collapses on itself. This happens because stars are stable due to the balance between pressure created by the fusion of Hydrogen into
Helium and gravity. The core of the star over time turns into denser and denser elements due to fusion until it reaches Iron. Iron is the densest element and cannot be
fused into any other element. At this moment, the balance between pressure and gravity shifts drastically and the star collapses on itself. If the star is big enough, it turns
into a Black hole. Otherwise it will turn into a Neutron star. We have a lot more to learn about Black holes. The idea of Black holes was proposed by Albert Einstein . It
was a common debate among the scientists whether they were real or not, until the first picture of a Black hole was recently taken. It was not a picture of the Black hole
itself, but of the superheated gas surrounding the black hole. This is because even light cannot escape the gravitational pull of a Black hole. The existence of Black holes
was also proven mathematically by recent Noble prize winner, Roger Penrose, Reinhard Genzel and Andrea Ghez. They developed a mathematical theory on the
existence of Black holes based on the ideas of Einstien's 'Theory of Gravity'.
Black holes can be of various masses. Some are about ten to fifteen solar masses, while others can be as massive as millions or even billions of solar masses! The largest
Black holes that we know of, has an estimated mass of more than 40 billion solar masses. The Black hole in the middle of our Milky Way galaxy is called 'Sagittarius A'. It
has an estimated mass of more than three million solar masses. Black holes also result in the formation of Quasars. These are the brightest objects in the Universe. They
can outshine entire galaxies. These are essentially super massive Black holes which are surrounded by superheated gas which causes them to be so bright.
Black holes do not exist for ever. They eventually evaporate by Hawking radiation, which is a process in which one particle of a Black hole escapes at infinity
while the other particle is trapped inside the Black holes horizon. Hawking radiation is a very slow process, so slow that by the time the last black hole will
evaporate, there will be no stars left in the universe. Black holes are just one of the many marvelous objects of the universe. There is so much more left to
discover in this vast Universe. I hope that one day, we will be able to solve some of the other greatest mysteries of the Universe.

Ashar Zahir,
Grade 4c

The Terrific Three

I always wondered what it would be like to go on adventures like the Famous Five. My team felt incomplete with me and my younger brother. I always wished for an
amazing pet dog like Timothy from the Famous Five. Me and my brother promised our parents to look after and love our pet dog. Guess what?! Yesterday we went for a long
drive to Pune. Our parents surprised us with a beagle pup. We named him Coco. He is a beautiful puppy.
I wonder whether Coco would enjoy adventures? Would he enjoy the beaches, sun and sand? Would he enjoy the hills and the meadows? Would he enjoy long drives, chasing
butterflies and camping?
Right now Coco is a tiny baby. So as of we are going to enjoy being at home and play with him till he is old enough to come out with us. Looking forward to many exciting days
with my brother and Coco.

Rudr Dube,
Grade 2

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