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SCIENCE BEHIND IT : WATER SHORTAGE
 Stars are formed in clouds of gas and dust, known as nebulae. Nuclear
 reactions at the center of stars provide energy to make them shine  The Earth is covered by roughly 336 billion gallons on Earth.

 brightly for many years. The exact lifetime of a star depends on its size.
 Massive stars burn their fuel faster than smaller stars and may only  But most of this is salty sea water. This got me thinking that

 last a few hundred thousand years. Smaller stars, however, last for  why can’t we use sea water by desalination. Desalination is
 several billion years, because they burn their fuel much more slowly.  the process by which salt is separated from sea water.

 Eventually, the hydrogen fuel that powers the nuclear reactions within
 stars, begins to run out, and they enter the final phases of their  Thermal desalination is basically boiling water and

 lifetime. Over time, they expand, cool and change color to become red  capturing the steam which is fresh water. But in the 1960s
 giants. The path they follow beyond that depends on the mass of the  a new process was discovered called Reverse osmosis. In

 star.
               this process the sea water is passed through a filter at


 Small stars, like the Sun, undergo a relatively peaceful and beautiful  high pressure which separates salt and water. The
 death, where they pass through a planetary nebula phase to become a  downside of these processes is that there is a byproduct
 white dwarf, this eventually cools down leaving a brown dwarf. Massive  called Brine. In the process of reverse osmosis, half of the

 stars experience a more energetic and violent end, wherein their
 remains are scattered about the cosmos in an enormous explosion,  water is brine and other half fresh water. Brine is hyper

 called a supernova. Once the dust clears, the only thing remaining is a  salty water. To dispose brine, they are usually discharged
 very dense star known as a neutron star, these can often be rapidly  into sea, river and lakes. Brine being heavier than normal

 spinning and are known as pulsars. If the star which explodes is  sea water sinks to the bottom of sea bed and can harm the
 especially large, it forms a black hole.
               flora and fauna. Even with its draw backs it is one of the

 In the 1970s, theoretical physicist Stephen Hawking made a remarkable  most stable methods. In the process of desalination the
 discovery: Black holes glow, ever so slightly, and, given enough time,  filter needs to be replaced at time to time. But it is also the

 eventually dissolve. This is known as “Hawking Radiation”.
               main supply of water to Saudi Arabia, UAE and California. My


 Even if we know so much about black holes, there is still so much to  take on this is that desalination would be a great help to
 learn. As they say we can never completely understand science and  supply of water if the brine supply, cost and energy needed

 there is always something to learn.
               would be reduced.


 Varad Apte [STD VIII]                                  Pradeep Bahenwal [STD VIII]
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