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Mangalyaan for Kids

It all started off with me trying to explain to my 7 year old about how a satellite works and how she is able to watch her favorite cartoon shows. Then from one planet to another, from one satellite to the other, from one small question to a whole chart of explanation to finally we mother-daughter duo decided that we wanted to build the Mangalyaan for the school science project. With our sky-shooting excitement levels, we knew we had to first carry out at least a basic research assignment on what, why and how was Mangalyaan.

The more I read, the more I realized the pride that we all should be holding for such an important mission. I am not too sure whose eyes twinkled more, mine because of the pride and information that I possessed or the little eyes of my 7 year old whose sparkled just by fanaticizing over what I kept sharing with her.












Well this is what we made based on our research about India’s Mangalyaan mission:


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This was pretty much all that she had to remember:

Mangalyaan is a satellite sent by India around Mars:A satellite is a small body rotating around planets – like the moon around earth (is a natural satellite) and other (artificial) satellites with the help of which we see TV.

The Model:

  • This dome is a fuel tank to run its own engine ( to correct its movement in space – from the earth)
  • These solar panels create electricity from the Sun to operate its own equipment.
  • The (funnel and disk) are antennae to be able to receive signals from earth and communicate.


  • Mangalyaan has instruments to check the air on Mars, and especially for Methane gas.
  • It has a special infrared (light rays that we cannot see with our eyes) camera to check the rocks and sand on Mars.
  • It has a special digital camera to take photos of Mars.

The orbit and operation: Mangalyaan is rotating around Mars and using its instruments. It is sending back all this information to us on Earth.

The trip:Mangalyaan was launched in space on 5th Nov 2013.It was lauched by the rocket called PSLV (polar satelite launch vehicle). It is in 4 parts (show on model). Each part drops away when the fuel in it is used up, and it keeps pushing Mangalyaan further in space. Finally the entire rocket drops away

When it was launched, it was rotated around earth 6 times in increasing orbits. This was to increase its energy by using gravity.


(To check how the satellite rotateduse ball and stick to demonstrate – the tension force in the string is like gravity)  Finally it was pushed out and sent towards Mars. It reached Mars on Sep 24 2014.

(As an example It takes 2 hours by plane to go from pune to chennai , and 24 hours by train).

It took Mangalyaan 9 months to reach Mars from Earth.

Finally our country definitely received a lot of accolades for this but I received one of the cutest smiles ever.  doc5















Some more related information about Managalyaan

1.  Created History:ISRO, or the Indian Space and Research Organisation, is India’s primary space agency. It has created history since its inception 44 years ago. Its space engine or Mars craft called Mangalyaan successfully entered Mars’ orbit in its first attempt on Wednesday, September 24, 2014.

2.   MOM:The Mars Obiter Mission or Mangalyaan was launched on November 5, 2013. After 15 months, it seamlessly floated into Mars’ orbit. This near impossible feat achieved by the scientists at ISRO has made India the first country in the world to achieve this task in its maiden attempt.

3.  The Mission:Mangalyaan was conceptualized to be able to gauge the resources required for planning, managing technology and operations of an inter-planetary mission. It will also look for indications of life on Mars such as the gas methane.

4.  The Cost:Mangalyaan has been termed the most cost-effective project with a total expenditure of Rs. 450 crores or approximate $ 73 million. Many are even calling it the cheapest Mars mission till date.

5.  Distance travelled:The mars craft travelled 650 million kilo metres from earth. If calculated, the cost comes up to Rs. 6.7 per kilometre. This turns out to be cheaper than a regular rickshaw ride in the city.

6.  Weight:Mangalyaan weighs 1,350 kgs and was ready in 15 months while NASA took five long years to gets its space mission, Maven ready. It is cuboid in shape and the main engine was referred to as Kumbhakaran or the sleeping demon which has now been awakened.

7.  World Standing:After achieving this unbelievable task, ISRO has become the fourth space agency in the world to have successfully completed a mission to Mars. It comes after the National Aeronautics and Space Administration (NASA) of the US, Russian Federal Space Agency (RFSA) and European Space Agency.


Gravity Waves

Einstein predicted the existence of the gravitational waves in 1915,this theory came to be proven only recently in February 2016 when the LIGO (Laser Interferometer Gravitational-Wave Observatory )detectors in Louisiana ,USA detected a change in length of the tube detector equal to about one-thousandth of the width of a proton, a revolutionary discovery for our times . This phenomenon is based on spacetime. Einstein said that space and time can be merged to form the single continuum of spacetime which can be imagined like a mesh or a net in the universe, the mesh containing the three axes of length, breadth and depth and also the fourth axis of time together forming the spacetime continuum. This mesh is curved by the presence of mass or energy forming a crater in spacetime, greater the mass of the body larger the crater, all other inferior masses tend to fall in this crater, a phenomenon known as gravitation.


Fig. 1 Spacetime

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Boltzmann constant – Putting it in perspective in Physics – Part 1

In this series, we will begin with the famous Boltzmann constant, and try to put it in perspective.

That is, its most basic form, original usage, significance, where else it is used, who were the people involved, some chronology, historical perspective, etc.IMG_0103_twentyfifteen-825x510

We’ll try to do this in small pieces, bite-size, non-overwhelming.

This article is only the overview of what we’ll go into a little deeper in following articles.

So we will start with the Boltzmann constant.

And its basic form in the Ideal Gas Equation.

We’ll look at its relation with the Universal Gas Constant and Avogadro’s number.We’ll look at these 2 terms a bit too.

Then we will take a look at where else this term is used. Natural candidates are terms where the name Boltzmann is used. That is:

  • Boltzmann distribution        
  • Boltzmann’s (Differential) Equation
  • Maxwell-Boltzmann distribution    
  • Maxwell-Boltzmann statistics          
  • Stefan-Boltzmann law

As it turns out, all of the above do use the Boltzmann constant.

Boltzmann and his constant (the constant named after him) mark an era in the development of physical science, of the inclusion of a statistical/probability approach. This was in line with the advent of investigation of microscopic matter as opposed to only macroscopic / deterministic/ Newtonian physics previously.

This led to the development of Statistical mechanics and its corresponding mathematical frameworks (Statistical ensemble – mathematical physics)

With his work, Boltzmann was instrumental for getting acceptance of matter as comprising of atoms and molecules.

This led to the led to the development of Kinetic theory–a key branch of Thermodynamics.

An early breakthrough in this field that helped build its foundations was Brownian Motion, involving Einstein and Perrin.

Statistical mechanics (its branch – Particle statistics) is used in Quantum Physics too, to describe the states of matter.


Bose-Einstein Statistics

Fermi-Dirac Statistics


In this context, some of the key scientists to look at are (intentionally mentioning their life-cycles to appreciate the sequence) :

  • James Clerk Maxwell (13 June 1831 – 5 November 1879)
  • Ludwig Eduard Boltzmann (February 20, 1844 – September 5, 1906)
  • Josiah Willard Gibbs (February 11, 1839 – April 28, 1903)
  • Max Karl Ernst Ludwig Planck (April 23, 1858 – October 4, 1947)
  • Albert Einstein (14 March 1879 – 18 April 1955)
  • Jean Baptiste Perrin (30 September 1870 – 17 April 1942)


Coming up with Part 2 shortly.


This is rambling article about human vision.

Blind spot
It all started when we were having fun with the “blind spot”. Its been known for ever that the blind spot exists. It is now well-known that is the position in the eye which has no receptor cells from where the optic nerve leaves for the brain.

I couldnt get it to work for it – but the wikipedia page worked perfectly for me. It was awesome !!!


Colours have always been fasicnating. Aesthetically, scientifically. We know that there are basic colours – red, blue and green – from which all other colours can be derived. Changing the intensities of these colours and mixing them can produce virtually every other colour. And can be very entertaining too. It doesnt have to be exactly these three colours, but can be any three colours from three appropriate group. Why 3 ? It turns out, and it seems so obvious in retrospect, that there are three kinds of cone cells in the eyes. These cone cells are responsible for colour perception and their photoreceptors are of three kinds – most sensitive to red, geen and blue !

It turns out then – that night vision – vision in dim light – which is colourless – is due to biology again. Rod cells are responsible for this vision, as opposed to cone cells. And unlike cone cells they dont have the photopigment in them.

Some notable scientific greats have been intrigued with colour and have focussed their energies there.
Schrodinger, the genius who did many things, but is mostly known as one of the founding fathers of the quantum theory, and his quantum mechanical wave equation. He published a number of papers in the field of color, color perception and colorimetry.
While on the topic, it was Schrodinger’s book “What is Life?” that led to an entire generation turning their energies to research in that line that eventually led to the discovery of genes and established the field of genetics. Continue reading

Rosetta – Philae and the Comet

Rosetta_NAVCAM_comet_67P_20140919_mosaic_625A news that caught my attention recently was about the spacecraft Rosetta, and that it had landed a module, Philae, on a comet.

I thought it was special because-
As compared to planets which seem stable and calm, a comet in my mind is a racing ball of fire.
Also a planet is this large thing, and a comet is small.

So am I implying that landing a vessel on a planet is common, but its special if on a comet ?

Of course there is no basis for my idle perceptions.
Landing sites on the Moon and Mars are pin-pointed in advance, and well achieived too. A planet is this huge hurtling, spininng massive sphere – subject to great forces, and creator of its own.
Exploratory vessels have their trajectories defined for years in advance. Satellites have their orbits planned, monitored and corrected. Its all very amazing and hi-tech.

Am I implying now that a comet landing is also no great deal ? :)

I guess I still find the idea of a comet landing very fascinating, almost unreal.
Here a some more stunning facts:

  • The Rosetta spacecraft was launched in 2004 – 10 years ago.
  • The comet, 67P/Churyumov-Gerasimenko, is a big rock, about 4 kms in it longest dimension.
  • On its way to comet 67P, Rosetta passed through the main asteroid belt, and made the first European close encounter with several of these primitive objects.
  • Rosetta was the first spacecraft to fly close to Jupiter’s orbit using solar cells as its main power source.

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Acharya Sir Jagadish Chandra Bose

Archarya Sir Jagadish Chandra Bose is one of the leading luminaries of Indian Science.

Incidences from the life of this extrememly talented individual highlight his exemplary value J_C_Bosesystem, his humility and his grit and determination. For example, when he was faced with discrimation he declined his salary and continued to work for 3 years, his research conducted in trying circumstances with meagre resources, or his disinclination of filing patents for his inventions.

However in this small article we only aim to highlight 2 of his inspiring efforts.


Radio research and wireless signalling – including use of semi-conductor

Sir Bose’s research in microwave waves allowed him to generate waves in the millimetre level (about 5 mm wavelength).

The first remarkable aspect of Bose’s follow up microwave research was that he reduced the waves to the millimetre level (about 5 mm wavelength). He realised the disadvantages of long waves for studying their light-like properties.

During a demonstration at Town Hall of Kolkata in the 1890s, Bose ignited gunpowder and rang a bell at a distance using millimetre range wavelength microwaves.
He used waveguides, horn antennas, dielectric lenses, various polarisers and even semiconductors at frequencies as high as 60 GHz. Which is quite mind-boggling, given the time and circumstances.
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