The window has a surface of 1.5 m2*... *The compartment has a volume of 12 m3*... *The train speeds 80 kph to the west*.The south wind is blowing at 5 mps*...*How quickly will the space be refreshed?*

Train speeds at 80kph i.e 22m/s
The train is moving towards west (22m/s) and wind to south which is (5m/s)

 So resultant wind through window
 √((22)^2 + (5)^2)
Which is a 13m/sA
At angle of {tan^-1(5/22+5)} which is 10.49 degrees.

Assuming Window is fully open
So 13m/s multiplied by dimensions of window
Then  13m/s × 1.5 cu. m = 19.5 cu.m

But the dimensions of compartment is a 12 cu.m ....so 19.5/12 = 1.625....so the space will be refreshed in 1.625 seconds

Aniket Kulkarni

Colonizing Mercury - The Idea

Mercury

The Idea of colonizing Mercury is hard to achieve as it requires more fuel to go to mercury than to escape Solar system!

Mercury being the closest planet to sun, has a surface temperature about 450℃ during midday and -180℃ during night.The Probes that have gone there had elaborated system of protecting themselves from heat. Protecting humans from heat will be difficult.

Mercury doesn't have atmosphere and it is constantly under exposure to solar wind, which possess high radiation.

The another big problem of colonizing mars would be "Why anyone would want to?" There's no good reason in doing the same. Probes  missions can be done better than any manned exploration.

So, it is easier to rather colonize mars than mercury which world is today looking forward to do so.

Aniket Kulkarni

Footnote : 

Image source : Mercury image

Mars - interesting facts you need to know

Mars

The fourth planet of solar system has got some interesting facts for you !

The largest mountain  as well as largest Volcanic Mountain in solar system is Olympus Mons located on Mars which is about 3 times that of Mount Everest!

The Northern hemisphere of Mars is lower than Sourthen Hemisphere of mars. If there was a ocean on mars, most of the water  would be on northern hemisphere.

Mars is a very cold planet, its 20% of  air freezes during winters !

Mars has two moons - Phobos and Diemos. Phobos circles mars 3 times a day while Deimos circles the planet every 30 hours!

Mars One Mission will be first ever mission to send humans on planet Mars in 2024. 705 candidates have been chosen and are being trained for the mission

Mars is next most planet  on which humans will start a living.

Mars see you soon !!

Aniket Kulkarni

Footnotes:

Image source : Mars image

Is there sound in space ??

Sounds in space

Have you ever wondered about existence of Sound in space. Can we talk to one another in space, the same way as we do talk on earth?

Well the answer is NO.

Sounds need medium to travel. Sounds travel through the medium called 'air' on earth. There is no air in space. So obviously, there cannot be sounds in space.

I'll take  an example,

The waves of water, in this example the 'water' acts as a medium for waves. 

Don't think that sound can only travel through air, even water and iron can act as a medium for sound to travel!

Sounds cannot exist in space since there is no medium for sound waves to travel in space.

If sound cannot tavel in space, how can astronauts communicate to each other ?

Well, astronaut wear a space suit which has air inside it which helps in communication.

They speak through microphone, which converts sound waves into electrical signals, electrical signals convert into radio waves.

Radio waves :

Radio waves can travel through space because radio waves are electromagnetic waves. Electromagnetic waves do not require any medium to travel because they are made up of both particle and wave. The best example for electromagnetic waves is 'light'.

 These radio waves enter into the receiver of another astronaut and convert into electrical signals and finally into sound waves. 

In this way,Astronauts communicate in space.

Aniket kulkarni

Footnotes: 

Image source: Sounds in space image

Milky Way - All you need to know

Milky Way

Milky way is a huge whirlpool that takes 200 million years to rotate once.

It is made up of  100 billion stars, dust and gas.

It is so much huge that, it takes 1 lakh light years to pass from one end to other end of milky way.

When a person sees milky way at night (yes it is possible to see milky way at night under specific conditions) , he sees only 0.0000025% of whole milky way.

The center of galaxy contains a black hole named sagittarius A* which is hard to see because of dust and clouds blocking view

The sun,earth and rest of solar system is located 27000 light years away from milky way's Galactic center, on the inner edge of a minor arm of galaxy, named orion arm.

If earth orbited the sun at the same speed that stars orbit at the centre of milky way, then earth would take only 3 days to revolve around sun.

Aniket kulkarni

Footnotes:

Image source :Milky way image

The 2.7% chance of asteroid hitting earth

99942 Apophis

Yes!! That is the name of the asteroid which is going to hit surface of earth on April 13th 2029 !!

The chance of hitting the earth's surface is just 2.7%. But we can ignore such a thing!

The mass of asteroid is estimated roughly to be 27 billion kg and  diameter to be 1210 feet.

On april 13th 2029, it will be nearest to earth and so there is a chance of the asteroid hitting earth's surface.

If the asteroid ever hits earth's surface, it will produce kinetic energy of 750 megatons ! The largest hydrogen bomb ever exploded, Tsar bomba in 1961 produced kinetic energy of  57 megatons. We cannot imagine the amount of damage it will cause to earth !

Asteroids also revolve around the sun but their path is highly elliptical.So, there is always a chance of their path intersecting the path of earth. That date is 13th of april 2029 and that date is not very far .

Only future can tell the consequences now !!


Footnotes :

Image source:Asteroid image

Moon - The importance of moon to earth

There would have been no life on earth, without Moon. Moon plays very important role to earth.

Formation of moon : 

The moon is believed to be formed when a planet of the size of 'Mars' collided with  earth billion of years ago. The debris  from the collision formed a ring around earth which later coalesced to form Moon.

What Role does moon play ?


1. Making earth rotation more stable. Without a moon, earth would wobble around and have more varied and less stable climate.

2. More mass, More gravity Hence more tides. We are here today because of these tides.

Tides : Tides bring in food and help dilute the waste products of creatures. Tides bring in fresh water(unsalted water). Tides prevent eutrophication by bringing in fresh water.

3. Without moon, there will be considerable changes in earth's path around sun.

4. Earth's rotation would increase. The fast rotation rate would lead to faster winds and stronger storms.

5. Without moon, the tilt of earth would increase which would create  a wild weather. Right now, due to moon earth is tilted at 23.5 degrees.

6. Without the moon  the tilt of earth would highly vary. With 0 (zero) degrees , we could barely sew sun. With 97 degrees tilt we will be found continuously 42 years in sunlight at a stretch and followed by another 42 years without sunlight.

Aniket Kulkarni

Footnotes : 

Image : Moon image

Can ISRO beat NASA ?? - ISRO vs NASA

Honestly, NASA is way ahead then ISRO.
But the question is  "Can ISRO beat NASA in coming years ?" The answer maybe Yes!

Budget of ISRO and NASA :

In 2017 NASA budget was 19.5 billion US$ and ISRO budget was 1.4 billion US$. NASA's budget is almost 18 times that of ISRO's budget.


ISRO is 4th Top space agency and it has gained this position in just  few years of its bloom. Recently ISRO sent 104 satellites in a single rocket only with the budget of 15 million dollars and NASA  admitted that it needed 100 million dollars to do the same.

On the other hand,

 NASA has well established space agency which has completed many missions successfully . It has more achievements in human missions as well.

ISRO has been excellent in past few years but its developing and performing missions in very low budget compared to NASA.

Comparing ISRO to NASA would be comparing a normal restaurant to a      5 star restaurant .Both the restaurants are good and serve different kind of needs for different group of people.   Both of them target different kinds of audience. Normal restaurant targets middle class people but 5star restaurant targets rich people.

Similarly ISRO is normal restaurant and NASA is 5-star restaurant. ISRO is walking and NASA is running on same road.

In future if INDIA has more developed budget and astronomy is high then there could be a comparison made between ISRO and NASA. But for now there is no competition between ISRO and NASA

Aniket kulkarni

Footnotes : 

Image 1 : Isro logo

Image 2 :NASA logo

Wormholes - The future to time travel

Let me tell you that wormhole existence is completely  Theoretical. No such thing is ever seen, but scientists claim that wormholes exists.

Way back in 1953,  Albert Einstein and Nathan Rosen used the general Theory of relativity to propose the existence of wormholes. Hence, wormholes are also known as Einstein-Rosen bridges.
Wormholes are passages or 'bridges' through Space-time. Time and space  are two aspects of a single thing called space-time.

A wormhole is a shortcut to travel in space time. A long distance can be covered through a shortcut which saves distance and time. 

A wormholes structure: 

Wormhole is considered of having two mouths at both ends which are of spherical shape and a tube like structure connecting the the two spherical shaped mouths.

Wormhole existence: 

Mathematically, Einstein's general relative theory states of existence of wormholes. But no traces ate found till date.

Can a man pass through wormhole?

The wormhole is highly unstable. It is known to collapse making nothing to pass through them. But that's no problem . Insertion of negative energy can bring the wormhole to stable conditions.
The other problem is the size! Wormholes are predicted to be at the size of microscopic level i.e. 10^ -33 centimeters making no human being to pass through it.

These are some factors why humans cannot pass through wormholes.
Currently we don't have any traces of wormholes. If we can find or create wormholes we can traverse thousands of years in fraction of second. Many enthusiasts say that travelling to future is easier than travelling to past.
The future is exciting!

Aniket kulkarni

Footnotes:

Image source: Wormhole image

How are black holes created ?

In simple words, black holes are created due to Implosion of stars.
But all stars which implode does not form black holes. It clearly depends on mass of stars.
A star's life is always in equilibrium with the force of nuclear fusion of Hydrogen to Helium(Stars are made of hydrogen atoms) and force of Gravitational pull.
Once stars run out of hydrogen atoms, the only remaining force is gravitational pull.
The further process clearly depends on the mass of star. We can categorize mass of star in three types :

1. Stars which have  mass less  than sun
(Less than 1 solar mass)

2. Stars which are about the mass of  sun(1 - 1.4 solar mass)

3. Stars which are much more massive than sun(more than 20 solar mass)

Lets study all three cases briefly one by one.
1. For stars which have mass less than that of sun :
When these stars run out of hydrogen atoms then there are no more nuclear reactions to fight gravity. The repulsive forces among the electrons within the star eventually  create enough pressure to halt  further gravitational process.

2. For stars which are about the mass of sun:
These stars end state will be a White drawf. No more fusion takes place and only heavier elements like oxygen, carbon remain out.It stars to cool down slowly.But it does not collapse further due to Electron degeneracy pressure.

3.For stars more massive than sun :

The fusion process continues further up the periodic table  to silicon, aluminium, potassium and so on up to ferrous(iron). No energy can be produced by fusing iron atoms together. Its the Stellar equivalent to ash.  It will get to white dwarf stage and keep collapsing. It will become a neutron star and still it shrinks. It gets denser and denser and collapses to a point where all mass of star is contained within the Schwarzschild radius and becomes a BLACK HOLE.

ANIKET KULKARNI

Footnotes: 

Image source : Black hole image

Can Humans Create new planet ?

Many of you may not agree with the following post.

But the best counter-question to the question "Can we create a new planet?" Would be  "WHY NOT ?"

The most intelligent creation on earth i.e. "Human" have vast capabilities to understand the things.

In the past 20 years human have  progressed very rapidly in technology field. NASA has been working on new projects of finding earth like planets. Those days are not far when we will start feeling to move out to another planet. The next planet which we can plan to move out is undoubtedly MARS.

So I just realized of being going off topic.

The question is " Can we create a habitable planet?"

So just think if you have many readymade shirts, will you create a new shirt or explore the shirts you already have and use them first.

The thing with the planets is the same . Why can't we just explore out mars ? We even don't have the latest Technology (currently) to create a new planet. Recently NASA has also confirmed about existence of water on mars. The reason why only mars should be our next planet may be the question. But there are many answers to this question.

1. It is near to earth.

2. Easy to reach out.

3. Planets venus and mercury have high temperatures.

4. Water existent.

5. Saturn,jupiter,neptune,uranus are gas giants having no solid surface.

So, the only planet we can think of moving out is Mars.

These are some reasons. Though research is going out. We don't now when what could show up. 

These were just my point of views .

Aniket kulkarni

Footnotes: 

Image source: Image

What is Supernova?

In simple words, Supernova is a phenomenon which causes due to explosion of stars. Supernovas outshine the whole of the galaxy and produce enormous energy. Supernovas can happen in two ways:

 1. The  FIRST type of supernovas happen in Binary stars. Binary stars, name itself states there are two stars. One of the stars steal or accumulate mass from another star and due to this heavy mass, the star eventually explodes and leads to supernova.

2. The SECOND supernova :is seen only in star which are more massive than sun (8-15 solar masses). A star's life is always in equilibrium  with the force excreted by the Nuclear fusion of hydrogen atoms and gravitational force excerted by star's gravity. The star's glow is only due to this nuclear fusion of Hydogen atoms to Helium atoms. When the stars run out of hydrogen atoms, the fusion reaction is stopped and the temperature rises. This rising temperature leads to production of heavier elements on the core in the below order:
Carbon
Neon
Oxygen
Silicon
Iron
Once Iron is formed, the gravity of the core collapses and it explodes which is called supernova.
But scientist think that the stars much more heavier than sun (20 - 30 solar mass) do not form supernova, but turn into Black holes. 

Aniket kulkarni

Footnotes: 

Image 1 link : Type 1 supernova

Image 2 link: Type 2 supernova