What rover will do in Chandrayaan 2 mission? - Chandrayaan Series

Chandrayaan 2 rover is a 6 wheeled robotic vehicle that works for 1 lunar day (14 earth days). This rover carries 2 main components. 

1. LIBS (Laser Induced Breakdown Spectroscope)
2. APIXS (Alpha Particle Induced X-ray Spectroscope).

Let's see the working of these 2 components.

LIBS:

It uses laser to shoot the surface and then characterizes plasma. The pulsed laser hits the sample by the average of 1000 pulses per second. On the contrary, it emits lights of different wave length in which the element can be easily identified. It takes about few seconds for LIBS to find the elements present on the sample.

APIXS:

It blasts alpha particles on the lunar surface and then measures X ray fluorescence.

Evloution of Chandrayaan 2 - Chandrayaan series

In this article, we may see about the evolution of our Chandrayaan, the struggules faced by ISRO to launch chandrayaan. 

In 1962, Indian National Commitee on Space Research was first formed under the Prime Minister Nehru. Vikram Sarabhai, father of India's Space Programme, changed INCSR to ISRO (Indian Space Research Organization). India launched it's first satellite Aryabhata on April 19, 1975. At that time, amny countries landed on the moon. India began it's journey to moon after the launch Aryabhata. 

In 2008, India launched it's own rocket on it's own land, Chandrayaan 1. It carries 11 scientific instruments. Among 11, 5 instruments belongs to India and the rest of the 6 instruments are belonging to various countries. Without charging them a single paise, we include their scientific instruments on our satellite. Chandrayaan 1 flew and sucessfully found the water molecules on the moon.

On 18th September 2008, the then Prime Minister Manmohan singh approved Chandrayaan 2. Chandrayaan 2 is a orbiter - lander - rover mission. India asked Russia to design lander. But , Russia hasn't designed Lander until 2015. Hence, India decided to make it's own lander as well as rover. Atlast they decided to launch Chandrayaan 2 on March, 2018. After some problems arise in lander, they postponed the mission. And they announced the launch on 14 July, 2019. Again due to some technical issues, they again postponed the date and planned final launch on 22nd July, 2019. The orbiter will be reach on Moon's orbit by September 6, 2019 (prediction). Let's wait and watch whether the mission will suceed or not.

Image of earth taken by Chandrayaan 2

(to be continued)

How Chandrayaan 1 found water molecules on moon? - Chandrayaan series

On July 21, NASA celebrated the 50th anniversary of moon landing. It has been exactly 50 years since the Neil Armstrong set the first step on the moon. On 21st July, 1969, he became the first man to land on the moon. On 22nd October 2008, India launched it's first moon mission Chandrayaan 1 which found the presence of water molecules on the moon. Let's see how it finds.

Is Water exist on moon?

When the sunlight falls on the moon, it's surface temperature might reach a temperature of 125°C. In such a case, if there is water present on the moon, all of the water would evaporate into vapor. Since the moon has no atmosphere, there is no place to trap vapor and thus the vapor releases into space. On the other hand, if the sunlight doesn't fall in the moon's surface, it's temperature might reach -173°C. For water to exist, it requires 0 to 100°C. So, it is cleared that liquid water doesn't exist on the moon. Ever since 1960's, many scientists believed that the craters (pits) present on the moon might have water. There is some region in these craters that is covered by shadows. That is, the shadows of the craters will fall on these regions. So, the shadowy regions never receive sunlight. So, scientists believed that in the regions that never received sunlight, the temperature must be below than 0°C. As a result of this, some water may exist there in the form of ice. This water may exists in the moon by 3 sources viz.,

1. Endogenic processes,
2. External sources like asteroids and cometary impacts,
3. in-situ production of water on the planet.

CHANDRAYAAN 1 ACHIEVEMENTS:

Moon Impact Probe

Chandrayaan 1 mission consists of orbiter and the Moon Impact Probe (MIP - ISRO). By crashing the moon impact probe on south lunar region, water molecules was detected on the moon. Scientists have estimated that 1.3 trillion pounds of ice might exists in the shadow of these crater. Later in 2013, NASA's LRO(Lunar Reconnaissance Orbiter ) went to the moon and found out the Shakelton Crater. It is found near the south pole. Chandrayaan's MIP landed near this crater. The same crater was analysed by LRO and it was discovered that 22% of it's water is covered by ice. The cost of this mission is just 386 crore rupees. After a year later, the problem arises from the orbiter. Due to this many instruments may fail to work. On 29 August 2009, the radio signals coming out of the chandrayaan stopped. After few days, ISRO declared that the mission comes into halt. ISRO planned that Chandrayaan would work for 2 years but it works for 312 days only. However as the mission accomplished 95% part of it, it is considered as a successful mission.

LRO

(To be continued)

Chandrayaan 2 Components - Chandrayaan series

Today, India has launched it's Chandrayaan 2 mission successfully. It was the first mission in the world to explore the south polar lunar region. Let's take a view on this mission.

MOON EXPLORATION HISTORY:

 The human exploration to moon began on 1959 by Soviet Union by the launching of Luna 2 mission . And then in 1966, they successfully launched Luna 9. In the year 1969, USA launched first manned mission to moon, Apollo 11 where Neil Armstrong, Edwin buzz Aldrin and Michael Collins successfully landed on moon and set their footprints and their flag. It was considered as a major milestone of human era. Between 1969 to 1972, 24 men traveled to moon. On October 22, 2008, India launched it's first moon mission, Chandrayaan 1 at Sathish Dhawan Space Centre, Sriharikota. In this mission, Chandrayaan successfully found the presence of water molecules on the moon. Now, India launches it's 2.0 version of Chandrayaan 1.

CHANDRAYAAN 2 - A OVERVIEW:

Chandrayaan 2 is a orbiter - lander - rover mission unlike chandrayaan 1 which is a orbiter mission. 

COMPONENTS:

These lander, orbiter and rover are carried into the space by the mightiest rocket ever built by India - Geosynchronous Satellite Launch Vehicle (GSLV) - Mark 3, the most powerful Indian rocket till now. This rocket consists of 

• 2 Solid boosters
• A core liquid booster
• Cryogenic stage.

SOLID BOOSTERS:

Chandrayaan launcher uses two S200 rocket boosters to lift off from the land. It is placed on both sides of the rocket. This S200 solid boosters was developed at Vikram Sarabhai Centre at Sriharikota. 

LIQUID BOOSTER:

The liquid boosters are powered by two vikas engines. It was developed by liquid propulsion system centre, which can carry about 110 tonnes of fuel (Dimethyl hydrazine).

CRYOGENIC STAGE:

Fuel - Mixture of oxygen and hydrogen 

Duration - 640 seconds

Chandrayan's C25 engine was designed and developed by ISRO's liquid propulsion system centre.

PAY LOAD FIRING:

It is a nose shaped cone present at the top of the spacecraft which is used to protect the spacecraft against atmospheric pressure and heating.

ORBITER

Weight; 2379 kg

Lifespan; 1 year

LANDER (VIKRAM):

Weight; 1471 kg

It is capable of generating 650 W of electricity. The Lander detaches from the Orbiter and lands safely on the lunar surface while the Orbiter scans over the lunar surface. After the Lander landing on the lunar surface, it will deploy rover on the moon.

ROVER (PRAGYAN):

• Six wheeled robotic vehicle
• Lifespan - 1 lunar day (14 earth days)

The Rover takes the soil sample and scans the lunar surface, studying it's topography, polar volatile deposits, mineralogy and elemental abundance in the moon.

Rover Pragyan carries two main components in it viz., 

1. LIBS (Laser Induced Breakdown Spectroscope)
2. APIXS (Alpha Particle Induced X-ray Spectroscope)
   
   

                                                                                                                                  (To be continued...) 

Why dry ice is so dangerous?

Dry ice is basically a solid carbon dioxide. The surface temperature of dry ice block is -78°c. This means it is much cooler than the normal ice which is made up of water. If the dry ice comes in contact with our skin, our cells begins to freeze and cause frostbite. In addition to this, storing dry ice in airtight containers is dangerous. This is because dry ice can sublimates(it directly converts from solid to vapor). Hence, in airtight containers, the gas produced can build up and exert pressure on the walls of containers which can lead to a dangerous explosion.

How do X-rays work?

X- rays are very high energy waves. They were accidentally discovered by Wilhelm Roentgen. As he did not know what they are, he named them X-rays. X-rays pass through many objects abut if the object density is more, they get absorbed and do not pass. Due to this property, X-rays are used to detect fractures, tumors etc., X-rays pass through the body and hit a thin photographic film. As our tissues are not dense enough, much of the X-rays pass through them and get detected by the film. Thus, casting a grey or dark shadow on the film. But, as the bones are much denser, they get absorbed by the bones and hence the bones appear white on the film. This allows the doctor to see the structure of the bone and thus helps to identify the fracture. 

Why do we love chocolates?

Normally, we love chocolates. This is because the chocolates contain Anandamide. This anandamine binds the special receptors in the brain, giving us joy and makes us to love chocolates. Some chocolates also contain substances like theobromine. It is thought that the theobromine makes our brain to produce anandamine by itself. In addition to this, the chocolates contain lot of sugars which releases dopamine that acts as a reward system. Dopamine makes us pleasure and feel good. As it makes us feel good, we tend to eat more chocolates to get the same feeling. And thus, we get addicted to chocolates. Also, the dry fruits like cashew, almond etc., are added to chocolates, hence the desire to eat chocolate increases.