Space Tech
Concept
Basic Concepts
Auroras
- Auroras are Charged particle interacting with charged particles of planet
Kepler's Law
Law 1 : Planets Revolve around the Sun in an Elliptical Path where sun appears to be Stationary at Focus
Law 2 : Speed Increases where at Perihelion and decreases at Aphelion
T^2 is directly proportional to R^3 where
T is Time Period of Revolution
R is the average distance between Sun and Planet
PS : This Gave Rise to Law of Gravity
Law of Gravity
Inside International Space Station there is a specific environment called as Micro Gravity. The Value of G is reduced in ISS, the Centrifugal Force it experiences due to circling of ISS around the earth counters the Gravity and Hence the Gravity Effect is Reduced
ISS Circles Earth at about 16 times a day
Newton's Concept of Gravity is different from Einsteins form of Gravity
Note : whether you move inside earth or outside earth, the G increase → Check Again
Centripetal & Centrifugal Force
Centripetal Force → is the Centre Seeking Force
Centrifugal Force → outward force in a circular motion. It depends on speed. More is the Speed of Revolution. More is the Centrifugal Force.
Example of Application of these Forces is ISS
If the Earth Starts to Spin Faster, The Gravity will be Less as the Centrifugal Force will counter the Centripetal Force i.e Gravity of Earth
If Earth Starts to Spin 16 time faster than present, then we will experience zero gravity in Earth.
Note
- If you move from Equator to Pole Gravity Increases
- Ass 1 : What will happen to G if you move inside earth
- Ass 2 : What will happen to G if you move outside earth
Concept of Light Years
It is the distance travelled by Light in Vacuum in 1 Year. Speed of Light is 2,99, 792.458 M/Sec or 3 * 10^8 m
Speed of Light Changes according to Medium.
For Example When Light Enters Water Speed of Light is reduced by 25%
But for Astronomical Distances, we consider the medium to be Vacuum. So we use light as a Measuring Unit to Measure Astronomical Distances
Description of any Element
- Subatomic Particles
- Protons - Positive
- Electron - Negative
- Neutron - Neutral
- Here No of Proton and No of Electron are Equal
- Atomic Number :
- No of Protons
- It is the identity of the Element it cannot be changed
- Mass Number
- No of Proton + Mass of Neutron
- Subatomic Particles
What is Watt
Watt is Joules Per Second. It is SI Unit of Power
Concept of Types of Speed wrt speed
- Speed of Sound is called as 1 Mach in Air which is 330 M
- Sub Sonic
- Commercial Flights
- Super Sonic
- Bullet from Gun
- Hyper Sonic
- Brahmos 2 & 3
Concept of Soft Landing
Soft Landing is Perfect Touchdown and NOT Crashing Intentionally or Otherwise. Till Now only USA, Russia and China have landed Safely on Moon
Israels Beresheet Mission also failed to soft land on Moon
Indians Vikram Lander also failed to Soft Land
Equipments Needed for Soft Landing
- Retro Rockets (Slowing Down)
- Position Detection Cameras
- Altimeters - Measures Altitude
- Touch Down Sensors
- Solar Panels
- Hazard Avoidance Cameras
Concept of Degassing
Unlike
Constituents of Universe
Real Matter → 5% Interacts with Electromagnetic Radiation Such as Light
Example : Galaxy, Solar System, Stars, Planets are all only 5% of the Universe
Dark Matter → 25% Dark Matter is a Matter which does not interact with Electromagnetic Radiation such as Light
Dark Energy → 70% It is the force which is causing expansion of universe. It is opposite to and is is much stronger than Gravity
Mains Questions Practise and Framework
Question
India has Achieved Remarkable success in unmanned space missions including the Chandrayaan and MoM but not ventured into a Manned Space Mission. What are the main obstacles of launching a manned mission both in terms of Logistics and Technology
Answer Structure
Introduction
- Definition - for complex
- Contextual Based - for simple topics → News Based + PM Speech
- Reports - Citing Data
Body
PESTAL Approach - Political Economic Social Technological Administrative Legal
Cyclical Approach
Conclusion
- Should be Positive
- By Recommendation by Bodies or Individual Experts
- Best Practises of Other Nations or Organisations
- SDG Goals
Actual Answer
PM of India in his Independence Day address announced that an Indian Astronaut would go in space by 2022, when India celebrates her 75th Year of Independence
Manned Mission
It is one of the most complex type of mission where humans are sent into space and then brought back to earth
Obstacles
Technological Obstacles
Protecting Humans Against Huge Gravity Forces generated due to acceleration
To Provide Earth Like Condition in Space - Air, Food and Processing Waste
Radiation is 10 times more in space than on earth
Logistical Challenge
Problem of Weight is a Fundamental Logistical Challenge. The Indian Launch Vehicles to send manned missions
Health Complications of Indian Astronaut
India does not have a Global Navigation System
India does not have Astronaut Training Facility
For Gaganyaan Mission Astronauts were sent to Russia for Training
Other Challenges
Funding
Low Participation of Pvt Sector in India
Not Well Developed Space Tech Eco System
Steps taken already by ISRO for Manned Mission
It has tested Re Entry
It has tested Crew Escape System & Mission Abort System
It has successfully tested Thermal Protection System
It has tested Deceleration and Floatation System
Gaganyaan Mission
India has planned Gaganyaan Mission by 2022 and has made collaboration with France for this Mission
Extra for Manned Mission
Under the Gaganyaan Schedule Three Flights will be sent in Orbit
First will be a Trial Flight
Second will carry a Robot called Vyomitra. It will understand the kind of stress humans will experience in space and to make changes accordingly
Third will be a Crewed Mission where three astronauts will be sent including an Indian Women. It will be sent to LEO at an Altitude of 300 to 400 KM for 5 to 7 Days
The Mission will be Equipped with Emergency Escape System & Mission Abort System etc
GSLV Mak 3 will be used as a Launcher. Estimated Cost of Mission is 10,000 Crores
Benefits of Manned Mission ( by PESTAL Benefit)
Scientific Benefits
It will spur research and development in areas such as Astro Biology & Planetary Chemistry
It will be a Gateway to create our own space station
It will boost the Science & Technology Level in the Country. India will be the fourth country to do so
Economic Benefits
It will boost industries - 60% of Equipments will come from Private Sector
It will Generate Jobs - ISRO Chief Says Gaganyaan Mission will 15,000 Jobs
It will attract investment for Future
India will increase its Market Share in commercial launch market
Social and Political Benefit
Youth will be inspired to take astronomy. It will help in cultivating skills - India has only 2% of Skilled Labour
It will establish India as a Key Player in Space Industry
Solar System
Introduction
Our Solar System is a Part of Milky Way Galaxy or the Akash Ganga
Nothing is Stationary in this Universe. Sun Revolves around our own Galaxy
Black Hole is a Region in Space where the density reaches infinity.
Name of Black Hole at the Centre of Milky Way is Sagittarius A Black Hole
Our Neighbouring Galaxy is Andromeda Galaxy
Position of Sun in Solar System
- Planets Move Around the sun in an Elliptical orbit or Path.
- Sun is Located at one of the focus of an Ellipse
- The One Away from Sun is Aphelion, Aur Jo Paas main hai Perihelion
- Velocity of Earth is Larger at Perihelion as compared to Aphelion. This is called as Kepler's Law
Structure of Solar System
Sun
Introduction
Sun is a 4.5 Billion years old Star. It orbits the Centre of our Milky Way Galaxy. For One Around it takes 230 Million years to make one round around the Black Hole
Sun may appear unchanging source of Heat and Light, but sun is a Dynamic Star
Dynamic → It is constantly Changing and Sending energy
Charged Particles sent out by Sun is called Solar Flares
What Powers the Sun ?
Fusion of Hydrogen (h2) powers the sun. For Fusion to happen, Plasma State is required.
Plasma is Super Heated Matter so hot that Electrons get ripped of from the atoms forming Ionised gas.
H2 → 2H+
in this State the atoms can overcome their natural electromagnetic repulsion and can then fuse, releasing huge amounts of Energy.
In Sun 4 Hydrogen Atoms fuse to form Helium Atoms. During Fusion of Hydrogen there is Loss of Mass. This Loss of Mass is converted into energy by this Equation. Fusion of 4 Hydrogen Atoms, Produces so much energy that It can light up a 60 Watt Bulb for more than 100 Years
PS : Temperature Inside Sun is NOT Sufficient to fuse Helium
Composition of Sun
Here Hydrogen is the Fuel and Hydrogen is Converted into Helium
in Future H2 will Decrease and Helium will Increase. Later the Sun Might Die.
Structure of Sun
Inner Layer
Core
Core is the Place where Fusion Occurs, because of Fusion it creates an Outward Pressure which Supports the Stars Gigantic Mass
Temperature of Core of Sun is 27 Million Degree Celsius
Radiative Zone and Convective Zone
They Transfer Heat from the Core to outer Layers through Radiation and Convection Respectively
Radiation : Radiation is the transfer of Energy from one point to another without the use of Medium
Convection : Transfer of Heat layer by layer by means of Medium
Example : Boiling Water or Making Tea
Outer Layer
Photosphere
Photosphere is the Part of Sun visible from Earth. It is this Part which we call as Surface of Sun
Chromosphere
It is a thin layer but it has very high magnetic field that controls flow of charged particle.
Corona
Corona is the Outermost layer where we see phenomenon of Solar Flares or Coronal Mass Ejection (CME’s)
Solar Flares → These are continuous flow of Charge Particles that Permeates the Solar System
Why Solar Flares are Produced ?
Plasma (Charged Particle) is rapidly rotating or moving. This Plasma is controlled by Magnetic Fields, However the Magnetic Field inside Sun Flips in Every 11 Years and this causes very intense Solar Flares
In Feb 2022, Solar Storms or Solar Flares destroyed 40 Satellites of Star Link Program of Elon Musk
If the Storms are Major, they could Disrupt electricity grids, fry satellites and disturb GPS
Facts About the Sun
The Sun does not Spin like a Solid Ball
Plasma Rotates at Different Speeds at Different Parts of Sun
At Equator it takes 25 Earth Days and at poles it takes 36 Earth Days
Temperature of Core is higher than that of Corona but Corona is the Hottest Part of Sun instead of Core
Hence, we can say that Corona is somehow hotter than the preceding layers
The Reasons for this Temperature Inversion is not yet clear
Concept of Chandrasekhar Limit & Future of Star or Future of Sun
What is Chandrasekhar Limit
Chandrasekhar Limit is the Value which gives us till what Mass of star will we get white dwarf. The Accepted Value is 1.4 times Mass of Sun
Summary of 3 Cases
Case 1 - White Dwarf → Till 1.4 Times Mass of Sun
Sun - Hydrogen has got exhausted. Here Two Envelopes will be formed. An Outer Envelope and an Inner Envelope will be formed
Red Giant Star - The outer envelope expands and appears to be red in color. It could engulf the inner planets (Mercury, Venus and Even Earth), While the Inner Envelope keeps on Shrinking, the Shrinking Envelope Increases the Temperature to such extent that helium starts to fuse
White Dwarf - When all the Helium has fused to form carbon, it shrinks further to form white dwarf
Case 2 - Neutron Star (High Mass Star) → 1.4 * M Sun < M Star < 3 * M Sun
Star - This is a High Mass Star. The Fuel Finishes and Two Envelopes are formed.
Red Supergiant Star - The Outer Envelope expands while the inner envelope keep on shrinking
Supernova - Because of Huge Mass the outer envelope explodes before getting lost into space. The Inner Envelope keeps in Collapsing, which leads to fusion of helium
Neutron Star - Because of Intense Gravity, Every Electron and Proton collapses to form Neutron and this is called as Neutron Star
- Magnetar : A Neutron Star having very high magnetic field
- Pulsars : They emit Pulses of Radio Waves
Case 3 - Blackhole (Very High Mass Star)→ M Star > 3 M Sun
Blackhole - Here Density Reached Infinity and even light cannot escape it
Planets
Conditions for a body to be declared as planet are
According to International Astronomical Union. A Planet must fulfill three criterias (2006)
It must orbit a star. In our case the Sun
It must have enough gravity to force it into Spherical Shape
Spherical because for any given volume, Sphere is the shape which has least surface area and hence least surface tension
In its orbit there should not be any other body of similar size - (Pluto Failed to have it)
It must be big enough that gravity has cleared away any other objects of similar size around the star
Pluto fails to fulfill the third criteria, Hence it is called as a Dwarf Planet
Other 5 Dwarf Planets are
- In Asteroid Belt
- Ceres
- Pluto
- Make Make
- Haumea
- In Kuiper Belt
- Eris
- In Asteroid Belt
M - V - E - M - J - S - U - N
All Planets have been named after greek gods
Inner Planets - Have No Rings
- Mercury
- Mercury is the closest, smallest, swiftest planet to Sun
- But it is not the hottest planet because it does not have a thick atmosphere
- It is the Swiftest Planet
- Venus
- It is the hottest planet because of atmosphere and it has co2 and h2so4. Hence Surface Temp is 450 degree celsius
- The Pressure here is 90 atm
- Hence because of Temperature and pressure it is uninhabitable
- Earth
- Mars
- It is called as Red Planet due to presence of Iron Oxide Fe + O2 → Fe2O3
Outer Planets - Have Rings
- Jupiter - King of greek gods
- has rings
- Saturn
- Most Prominent Ring is of Saturn
- Uranus
- It is because of tilt that earth has seasons
- uranus is the only planet with 97.7 tilt
- Hence it appears to be rolling on its orbit
- Neptune
- Whipped by Supersonic Winds
- Mercury
Small Body System of Solar System (Asteroid, Meteors, Comets)
Introduction
They are leftovers from the Formation of our Solar System i.e 4.6 Billion Years Ago. While Planets and Moons have changed over Millennia. These small chunks of ice, rock and metal have not. So they are like Fossil Records of this Universe
Asteroids
Asteroids are space rocks which have size less than that of planets but greater than pebble. They are Airless. Most of these Asteroids are found in Asteroid belt
Asteroids orbit the sun
but some of the asteroids are even found in the orbits of Larger Planets and these Asteroids are called as Trojan Asteroids
Meteoroid
A Debris in Space or Collision leads to creation of Meteoroid
Meteors are also space rocks but of pebble size. They are also called as Shooting Stars but are named Differently depending on where it is.
Meteor is called as Shooting Star → Because of Its Burning due to Atmosphere
Comets
Comets are Frozen leftovers from the formation of solar system. They form Tail which stretches millions of Kilometers.
When it revolves around the sun, the heat of sun vaporizes ice and this forms the tail
The Direction of Sun is always away from Sun
Difference between them
| Asteroids | Meteors | Comets | | --- | --- | --- | | Made up of Rocks size greater than pebble and less than planet | Made up of Rocks size of pebble | Made up of Ice | | | Has a Tail due to Burning inside Earth's Atmosphere | Has a tail due to Evaporation of ice (very far away from Earth) | | Its Orbits the Sun | It Depends, If it enters the Earth Atm, it will die out | Its Orbits the Sun |
What is a Constellation
It is a Group of Visible Star forming a Perceived pattern or outline
Leonid Meteor Shower
Some Debris from Leo Constellation entered Earth's Atmosphere
Leonid Meteor Shower is an Annual Spectacle, In Night Sky in November It turns into A Meteor Storm in every 33 Years or So
In 2022, It was active between Nov 6 and Nov 30 with peak activity observed around Nov 17
The Debris that forms this Meteor Shower comes from Leo Constellation
Kuiper Belt
It is a donut shaped region of icy bodies beyond the orbit of neptune
Kuiper Belt is one of the source of comets Nasa has Sent a Mission to Kuiper Belt known as New Horizons Mission. It has found a body named as Arrokoth (Earlier Name is Ultima Thule)
Oort Cloud
- It is the boundary of Sun’s Gravitational Influence. It has never been directly observed but predicted Mathematically
- It is also a source of Comets. However the comets have highly elliptical path which originate in Oort Cloud
Beyond Solar System
- Black Hole
- Event Horizon
- Singularity
Satellites
Introduction to Satellites
A Satellite is an Object which revolves around, a body because of the Body's Gravity
Need of a Satellite
- For Bird Eye View of a Large Part of Earth and can cover the complete earth as well
- GPS and Cartography → Looking Earth from Outside
- Tele-Communication
- It can also help in looking deep into space and have a view better than telescopes on earth → for Astronomy
Parts of a Satellite
All Satellites have two parts in common, first is a power source and second is antenna
Power source can be solar panelled or batter based or could even be nuclear based
Antennas are to send and receive information from earth stations
There are 2 Types of Satellites on the basis of Origin
- Natural Satellite
- Example Moon is a Satellite of Earth
- Earth is a Satellite of Sun
- Artificial Satellite
- Artificial Satellites are objects which are intentionally placed into orbit
- Natural Satellite
There are 4 Types of Satellites on the basis of Usage
Tele-Communication Satellites
Before Telecommunication Satellites, Transmissions were difficult for Long Distances. The Signals which travel in straight line
Communication Satellites act as a third point in space where Signals are sent and then the signal could be directed to the receiver or it could be relayed to another satellite
Examples : INSAT & GSAT
Telecommunication Satellites are Essentially Placed in Geostationary Orbits
Remote Sensing Satellite
Remote Sensing means Observing and Measuring our Environment from a DIstance. Output of Remote Sensing Satellites is generally in the form of Images. Several Application Areas of Remote Sensing Satellites Are
- Agriculture
- Mineral Prospecting
- Water Resources Finding
- Observe Weather
- Disaster Protection and Management
- Observer Env and Forestry
Examples
- IRS - Indian Remote Sat
- RISAT
- CARTOSAT
- OceanSAT
- Bhaskara
- Saral
- Artiga
Navigation Satellite
It is a system of satellites that provides autonomous geo spatial positioning
There are Two Types of Navigation System
- Global Coverage Navigation System
- GPS of USA
- GLONASS of Russia
- Regional Coverage Navigation System
- Galileo of Europe
- BeiDou of China
- Navic (Earlier IRNSS 1A) - India
- Global Coverage Navigation System
Space Exploration Satellite
- They are also called as Probes so as to “Studying”
- These Space Probes send back detailed pictures and atmospheric data of planets and other stellar phenomenon
Cubesat (Very Small Satellites)
They are smallest of satellites sent for a very specific purpose such as taking photograph for a particular incident or observation of earth
Examples of Mission
- Chandrayan Mission 1 & 2
Orbits
Introduction
What is an Orbit
Orbit is Essentially a curved path that an object takes in space around another object due to gravity
The Path can be circular or elliptical
PYQP from Orbits
Types of Orbits are
Concept of Plain of Earth
LEO - Low Earth Orbit
Features of LEO
Altitude - 160 KM to 1000 KM from Surface of Earth
There plains can be tilted that is Leo Satellites do not always have to follow a particular path around the earth in the same way
Tele Communication Satellites cannot be placed in Low Earth Orbits
Reason - 16 Times a Day LEO Circles Earth - Due to High Speed It is not viable for Tele Communication Signal Relay
International Space Station is placed in Low Earth Orbit at about 400 KM from earths surface, it circles the earth 16 times a Day
Yuri Gagarin in 1961 went to Low Earth Orbit. Space War period between Russia and USA
Uses of Low Earth Orbit
- Satellite Imaging
- Weather Forecasting
- Remote Sensing
GEO Synchronous Orbit
Introduction
- Meaning of Geo Synchronous - Satellite is in Sync with Geo i. Earth
- These Satellites are in Sync with Earths Rotation i.e the Rotation Speed of Earth is equal to Revolution Speed of Satellite
- If Earth Rotates in West to East Direction in 24 Hours then the Satellite would also Rotate in West to East Direction in 24 Hours
- A Satellite Above Delhi will always appear to be above Delhi all the time
Type 1 → GEO Stationary Orbit (Special Case of Geo Synchronous Orbit)
- Geo Stationary is only on the Equator Plain
- Tele Communication Satellites are placed into Geo Stationary Orbits
- Only 3 Satellites in Geo Stationary can cover the Whole Earth
- It cannot change the plain
- GSLV was designed to send to Higher Altitude of Geo Stationary
Type 2 → Sun Synchronous Orbit (Special Case of Polar Orbit)
It is a Particular Kind of Polar Orbit.
Satellites in SSO visit the same spot at the same local time i.e it is in sync with day and night timing of earth
A Satellite above delhi if it appears at 8 AM then next day also it will appear at 8 AM
Altitude is of 600 to 800 KM and the speed at 800 KM Altitude is 7.5 KM/Sec
Escape Velocity is the Velocity needed to escape the Velocity of any orbit. Escape Velocity of Earth is 11.2 KM/Sec
Speed of SSO is near to Transfer Orbit
Difference Between GEO and SSO
MEO - Medium Earth Orbit
- Any Orbit between 1000 KM & 36000 KM is considered to be Medium Earth Orbit
- LEO<MEO<GEO
- MEO consists of al the orbits between Leo and Geo
- It is similar to LEO in that it does not have to take the same path around the sun that is they can change their plain
- It is commonly used by Navigation Satellite
- Example : Galileo Constellation of Satellites is placed in NEO
Polar Orbits
- Polar Orbits are a Type of LEO as they are of Low Altitude and they pass over the North and South Pole
- Satellites in Polar Orbits need not pass exactly over the North and South. 20 to 30 degree deviation is still considered to be polar orbits
- Satellites Appear to be moving in North South Direction instead of West to East
- PSLV was designed to send to Lower Altitude of Polar Orbits
Transfer Orbit
Transfer Orbit are special kinds of Orbits that are used to get satellites from one orbit to another
we have chosen an elliptical orbit as transfer orbit where the Apogee is equal to radius of Geo Stationary Orbit
When the Satellite Reaches the Apogee, Thrusters or Engine is fired to make it enter into GEO Orbit
At the Apogee every time we fire thrusters to enter into another Orbit
Example : Use of Transfer Orbit in reaching Mars in Mangalyaan Mission
Concept of Lagrange Points
It is name in honour of Italian French Mathematician Joseph Louis Lagrange. He was finding solution to the famous three body problem
Lagrange Points are Points in Space where gravitational forces of sun and earth ( or any two body) combine in such a way that a spacecraft could remain stable and thus can be anchored relative to earth.
There are 5 Such Points, Three of them Lie in the Line Joining Sun and Earth.
- L1 - Lies Between Sun and Earth
- Gets an uninterrupted view of the sun without eclipses
- Earths Magnetic Filed Influence is not observed at L1
- It is millions of KM away from Earth
- Any Satellite Placed here Needs Less Fuel Consumption compared to other points in Space
- Example of L1 Objects Are :
- LISA Pathfinder
- Aditya L1 Mission
- Deep Space Climate Observatory
- L2 - Lies Behind Earth
- Gets Clear Picture of Deep Space
- Examples
- GAIA - ESA (European Space Agency)
- James Web Telescope
- L3 - Lies Behind Sun
- Scientist have not been able to find any use till now for this
- L4 & L5
- The Other Two Points Lie at the Apex of Equilateral Triangle by Joining Sun and Earth as Base
- L4 - Leads
- L5 Lags
- Compared to L1 L2 & L3 → L4 & L5 are more stable points
- Objects found orbiting in L4 & L5 are often referred to as Trojans
- L1 - Lies Between Sun and Earth
Technology
Various Space Agencies
- ISRO → Indian Space Research Organisation
- NASA → National Aeronautics and Space Administration
- ESA → European Space Agency
- JAXA→ Japan Aerospace Exploration Agency
- Roskosmos → Russian Federal Space Agency Russian Federalnoye Kosmicheskoye Agentsvo
- CSA → Canada Space Agency
- ISA → Italian Space Agency
Rover
Is a vehicle that moves around in the planet or astronomical object
Lander
A space craft that lands softly and then stays there at rest and does all other functions which it has to do
Orbiter
Orbits plants or astronomical objects.
Missions
There are 4 Types of Mission (Complexity Increases from 1 to 4)
- Fly By Mission
- It is the Simplest Type of Mission where a Probe or a Satellite Flies past a Celestial Object and Takes some Photographs.
- Example: Parker Mission was sent to sun but wrt to Mercury and Venus it is a Fly By Mission
- Orbital Mission
- The Probe enters into the Gravitational Influence of Celestial Body, It circles the Body and Makes observation of Atmosphere and Surface
- Lander + Rover Mission
- A Probe is Sent Down on the Surface of Body
- Concept of Soft Landing → Soft Landing is a Critical Technology to achieve this stage. Soft Landing means not crashing down, Intentionally or accidentally on the Surface of celestial body
- Rover is a Mechanical Robot which moves on the Surface of Celestial Body and Collects Samples
- Manned Mission (Human Mission)
- Astronauts are landed on the Celestial Body or Sent to Space ( GEO )
- Examples
- Yuri Gagarin - First Manned Mission
- Apollo 11 - Moon
- Artemis Mission
- Gaganyaan Mission
- Fly By Mission
Missions to Sun
Past and Present Mission
Parker Mission
- It was Launched in 2018. It was named after U G Neuman Parker who first theorised the concept of Solar Flares or Solar Winds
- The Objective of this mission is to study Suns Corona which gives rise to Solar Flares
- Parker Mission touched Suns Corona and then it moved out
- Corona is Considered to be the Least Dense Part of the Sun
- All Major Equipment Lies Behind the Sun behind a Shield
- The Shield is made up of Two Layers
- Outer Layer - Carbon Carbon Composite
- Inner Layer - Simple Carbon Composite
MMS - Multi Scale Magnetospheric Mission
It was sent in 2015 and it used 4 identical space crafts in a pyramid shape to measure the magnetic field lines and charged particles in three dimensions
It will study how suns and earths magnetic filed connects and disconnects transferring energy from on to another
Concept of Magnetic Reconnection
It is a fundamental process that taps energy stored in magnetic field and converts it into heat and energy
this reconnection is believed to trigger auroras
In Norther Hemisphere → Aurora Borealis
In Southern Hemisphere → Aurora Australis
Auroras are colourful Night Sky Occurring due to interaction of Suns Charged Particles with Earths Atmosphere
When it Interacts with Oxygen is Gives Green and Red Color
When It interacts with Nitrogen it Gives Blue and Purple Color
Jupiter is said to have the Strongest Aurora wrt to Solar System
SOHO - Solar and Heliosphere Observatory
- It is a Joint Mission of NASA and ESA
- It was sent in 1995 and it was meant to operate till 1998 but it has survived for decades
- Its objective was to study all the layers of the Sun and the Solar Winds
Hinode
Planned and Future Missions
- Helioswarm Mission
- Helioswarm will have a Swarm of 9 Space Crafts
- It will Measure the fluctuations in Magnetic Fields and Motions of Solar Winds
- MUSE - Multi Sat Solar Explorer
- It is of NASA
- Its Objective is to Understand, the forces driving heating of Suns Corona and the Sub Sequent Eruptions, Which are foundation of Space weather.
- Aditya L1
- ISRO is preparing for its scientific expedition to Sun. It will be placed in Lagrange Point L1 where it will get uninterrupted view of the Sun and also less fuel will be required
- Its objective is to study corona, chromosphere, photosphere and solar winds. Essentially its interested in studying the Outer Layer
Missions to Mercury
Least Explored by Humans
Mercury
It is Names After Swiftest Roman God.
It does not have any moon or any rings.
Atmosphere of Mercury is very thin and composed of Traces of Oxygen, Hydrogen, Helium, Sodium and Potassium
Mercury has a very high range of temperatures
It has a very high range of Temperatures
During Day → 430 Degree Celsius
During Night → -180 Degree Celsius
It is also known as Cannon Ball because 85% of its volume is made up of Metal
Missions
Past and Present Missions
- Mariner 10
- It was the First Fly By Mission of NASA to Mercury in 1973
- Messenger was sent in 2004 and it reached Mercury in 2011
- The Mission was completed in 2015
- It was deliberately brought down on the surface of the planet after the mission got over
- Messenger
- Took Around 6 to 7 Years to Reach Mercury
- It is by NASA
Planned Mission
- Bepi Colombo
- It is a Joint Mission of ESA and JAXA
- It was sent in 2018. Initially it will be fly by and by 2025 it will become Orbiter to Mercury
- Mariner 10
Missions to Venus
Venus
- It has been named after the Roman Goddess of Love and Beauty
- It rotates backward i.e Sun Rises in the West
- It is the Hottest Planet in Solar System because it has high concentration of of CO2 and H2SO4
- It has no rings and no moon
Mission
Past and Present Mission
- Mariner 2 - 1962
- NASA, Fly By, 1962
- Venera 13 - 1981
- It is by Roscomos
- It is the first space craft which survived for few hours on Venus surface
- It was sent in 1981
- Magellan - 1989
- NASA, 5 Year Mission ended in 1994
- Sent in 1989
Planned Missions
- Da Vinci
- By NASA
- To be Launched in Late 2020’s. It will send a probe down
- It will be sent after Veritas
- Veritas
- By NASA
- Orbiter Type
- Sent by 2027
- Envision
- By ESA
- Orbiter Type
- Shukryaan
- India’s Mission to be Launched in December 2024
- Its an Orbiter Type Mission
- Mariner 2 - 1962
Missions to Earth’s Moon
Most Explored Object by Humans
Past and Present Missions
- Apollo 11 (USA)
Russia had sent Yuri Gagrin into Space in 1961
John F Kennedy the then president of USA challenged NASA to send a Maned Mission not to Space but to Moon
NASA was successful in doing so in 11th attempt of Apollo Mission
Apollo Mission started in 1968 but first human landing was done in 1969 in which two astronauts landed on the Moon
Here, Neil Armstrong and Buzz Aldrin where as Michael Collins stayed in the Capsule
It has two modules
Command Module - Had Space for Three Astronauts → Orbiter Module
Command Module Carried Lunar Module
Lunar Module - Had Space for only Two Astronauts → Lander Module
This Landed on Moon
Launch Vehicle was the Saturn 5 Rocket
Challenges of Sending Manned Mission
- Maintaining Temperature and Pressure
- Hence for Human Like Accommodation - Weight of
- Beresheet (Israel)
- Luna (Russia)
Future Missions
Artemis
- Artemis is derived from Greek Word which means Goddess of Moon
- It is a Series of Increasingly complex mission that will enable human exploration to moon and mars
- The Series could go from A1 to A8
- A1 - is non crewed Mission → Sent
- A2 - Will be Crewed → 2024
- A3 - Moon Landing and Sub Sequent Plans → 2025
- This Program is Led by NASA and it involves other space agencies like ESA, JAXA, CSA
- The Idea is to Establish a Base Camp on Surface of Moon and a Gateway in the Lunar Orbit which will serve as outpost for onward missions
- Components of the Mission Are
Crew Module → ORION
Launch Vehicle → SLS (Space Launch System)
Support Missions
It will also have support missions, here robotic landers will deliver scientific instruments and rovers to Lunar Surface after Artemis 1
Change 4 & Change 5 (China)
- It was the first successful mission to send lander and rover to dar side of the moon
- It is the side which we never see, so it has no line of sight for communication with earth
- To Solve this Problem, China Placed a Relay Satellite in Lagrange Point of Earth and Moon where it had clear view of both
- This Mission was
- Lander
- Rover - Yutu 2
Capstone
KARI (Korea)
Luna 25 (Russia)
Indian Missions to Moon
Chandrayaan 1
- It was sent in 2009
- It was India’s first Lunar Mission
- One of the Significant Findings of Chandrayaan 1 was presence of water on Surface of Moon
Chandrayaan 2
- Sent in 2019
- Launched by PSLV
- Consisted of Orbiter, Lander or Rover all developed in India
- The Lander was called Vikram and it crash landed during the final phase of descent
Chandrayaan 3
It is mission repeat of Chandrayaan 2, it will also have a lander rover and a propulsion module to attempt soft landing
- Apollo 11 (USA)
Missions to Mars
Past
- Curiosity
- Mission of NASA
- It is the Largest Rover Sent to Mars and it landed in 2012
- It has a very unique power system, as it has Plutonium Based Power System
- Generates Electricity from the Heat of Plutoniums Radioactive Decay
- For Soft Landing Curiosity used Parachute and Retro Rockets were fired during the final seconds to reduce the descent speed
- Insight
- Mission of NASA
- It is a Lander and its objective is to study the interior of Mars
Present
Perseverance (NASA - USA)
- Perseverance was launched in July 2020 and it landed on Mars in Feb 2021
- It was timed for launch between July and Aug of 2020 when the relative position between earth and mars was good for landing on Mars
- Perseverance is the Name of the Rover. The Rover has a Drill to collect samples from Surface of Mars
Ingenuity
- It flew to mars attached to belly of Perseverance. It is a Helicopter
- in April 2021 it made history, by becoming the first aircraft ever to make a powered flight on ANOTHER PLANET
- Tianwen-1 (China’s Mission to Mars)
- It is a Orbiter, Lander and Rover
- It Landed in May 2021
- China has become the second nation ever to successfully land on Mars
- The Name of the River is Zhurong
- Hope (UAE)
India
PYQP
Mangalyan MoM 1 (India)
- Sent in 2014
- Orbiter Type of Mission
- India’s First Inter Planetary Mission
- ISRO became the fourth agency to reach Mars (First Three - NASA, ESA, Roscomos)
- India became the first asian nations, first nation to do it in first attempt
Mangalyaan MoM 2 (India)
- Will be second interplanetary mission planned for launch in Near Future
- Will Consist of Orbiter, Lander, and Rover
- Curiosity
Missions to Asteroids
Past
- Osiris Rez
- DAWN - Ceres & Resta
- NEAR
Present
Mission Lucy
- Lucy was the name of Australopithecus Afarensis
- Mission Lucy is the first mission to explore the Jupiter Trojan Asteroids
- Lucy whose skeleton provided unique insight into human evolution it is 3.2 million ancestor of humans
- By Studying a Trojan Asteroid of Jupiter it is believed that we could get inside evolution of the universe itself
Mission Dart
- DART - Double Asteroid Redirection Test
- Dart was designed to evaluate kinetic impact technique by striking aan asteroid with a space craft
- the test involves flying a dart space craft at high relative velocity into the smaller of the two asteroids
- it also carried a cube sat which was released prior to the impact to take the image of the impact
AIDA Collaboration
Along with ESA’s HERA Mission DART makes up the International AIDA Collaboration - Asteroid Impact and Deflection Assessment
Missions to Jupiter
- About Jupiter
It is the largest planet
It has been named after king of ancient roman gods
It is mostly made up of hydrogen and helium
It has a faint ring made up of dust and not of ice
It has more than 75 Moon - 4 Imp ones are
- Lo
- Europa
- Ganymede
- Callisto
It has three degree tilt hence it has no season
It has the shortest day in the entire solar system
Amount of water in Jupiter is critical to understand how solar system was formed
Unlike Earth Solar Winds couldn't blow away earths Initial Atmosphere because of the distance. So Jupiters Atmosphere ought to have differently from Earths Degassing Mechanism
On Jupiter Due to Huge Atm Pressure Hydrogen has Liquified
Natural Gas(CH4)→ Compressed → CNG (Compressed Natural Gas) → Compressed → LNG (Liquid Natural Gas)
How can we change the state of gas to liquid → by Reducing Temperature or Increasing Pressure
Jupiter has taken most mass from the sun. Mission Juno analysed the Heavy Metals of Jupiter which are no linger present on earth.
Jupiter has the strongest auroras
Past Missions
- Voyager 1 & 2
- Hubble Telescope
- Galileo 1989
Present Missions
PYQP
How Does Juno Mission of NASA Helps to Understand Origin and Evolution of Earth (150 Words or 10 Marker)
Mission Juno
- It arrived at the planet in 2016
- It has observed its liquid hydrogen atm and surface
- It has studied the heavy metals
- It has studied the auroras
- Importance of Water, Heavy Metals and Atmosphere by Degassing wrt Earth
Future Mission
Europa
It is a future mission which will study the europa moon of Jupiter
- About Jupiter
Mission to Saturn
- About Saturn (Homework)
Past Missions
- Casinin Huygens
- It was a join endeavour of ESA and ISA
- Huygens was a probe which parachuted on the largest moon of Saturn i.e Titan
- After 20 Years of Exploration Cassini was plunged down on Surface of Saturn in 2017
Mission to Uranus and Neptune (Not So Important)
Voyager 1 & 2
After Studying Outer Planets it has moved out of Kuiper Belt
Hubble Telescope
Mission to Pluto
New Horizons Missions
This Mission helped in Discovery of Two Moons of Pluto which are Kerberos and Styx
Voyager 1 & 2
Hubble Telescope
PYQP Prelims
Hubble Telescope & James Web Telescope
Concept of Electromagnetic Radiation
Concept of Wave
Diag : Transverse Waves 👇
- Details of a Wave Formula
- Crest - The highest part of the wave is called the crest
- Trough - The lowest part is called the trough
- Wave Length - the distance between two crest or trough
- Amplitude - the greatest distance that a wave, especially a sound or radio wave, moves up and down
- Frequency = 1/T = f → the number of waves that pass a fixed point in unit time
- Wave Speed
- Speed = Distance / Time
- Wave Speed = Wave Length / (1/T) = λ * f
- There are Two Types of Waves
Mechanical Waves
- They Need a Medium to Propagate ; Example : Sound Waves
- There are Two Types of Mechanical Waves
Transverse Waves
Example : Gym Main Rope Move Karna
Examples : Mexican Wave in Football
Direction : Up & Down
Vibration : forward
Here Vibration is Perpendicular to Direction of Wave
NOTE: All Electromagnetic Radiations are Transverse Waves
Longitudinal Waves
Example : Spring
Example : Pushing Someone in Line in school and everyone falls
Direction : Front
Vibration : Front
Here Vibration is in Direction of the Wave
Surface Waves
Non Mechanical Waves
They Don’t Need a Medium to Propagate; Example : Light Waves
- Details of a Wave Formula
Concept of Electromagnetic Spectrum
Afer Gamma Rays → Cosmic Rays
All these Electromagnetic Radiations have same velocity / speed. Here the difference lies in the frequency and Wave Length
Here λ & f are inversely proportional like a Sea Saw
Hence, v = λ * f → Hence Wave Length and Frequency Varies
When Light / Sound Enters Water → Wave Length Changes but Frequency Remains Same. Hence the Velocity Changes too
Cosmic Rays :
- Have Highest Frequency
- Produced During Most Violent Cataclysmic Events such as Collision of Neutron Star or Merger of Black Holes
- They have Lowest Wavelength
Home Work
Sound Speed Increase or Decrease, Add Salt, Increase Temp, Increase Pressure → What Happens ?
James and Hubble Telescope
Type of Light Captured by these Telescopes
- James Web Telescope Captures Infrared Rays → Hence this is more visible
- Hubble Telescope Studies Visible Light
Hubble Telescope
- It has been names after Edwin Hubble
- It was a space telescope that was launched in 1990 in LEO and still remains in operation
- It observes in the ultraviolet and visible part of spectrum
- Its primary mirror has a size of 2.4 Meters
- Significance
- It has made more than 1.4 million observations.
- It has helped in discovery of plutos moon.
- It has captured merging of galaxies
- It has probed supermassive black holes
- It has captured comet colliding with Jupiter
- Hence as helped us in making and stuyding obervsation of universe.
- It observes ultraviolet and visible light
James Web Telescope
- It has been named after James Web who was the architect of Apollo Mission of NASA
- It is the most powerful infrared Telescope of NASA, ESA & CSA
- It was sent on 25th December 2021. it is considered to be successor of hubble telescope and will complement its discoveries
- Features
- Makes Observation in Infrared Region
- It has a Large Mirro which has a Diametere of 6.5 Meter or 21 Feet
- This Mirro was so large that it had to be folded to be sent in a launch vehicle
- It has been placed in Lagrange Point L2 in space
- It has a unique Heat Shiled Mechanism. It has a five layered sunscreen
- Cost of this Mission is 10 Billion US Dollar
- 1 Million Dollar is 8 Crores
- 1 Billion Dollar is 8000 Crores
- 10 Billion Dollar is 80,000 Crores
Difference Between Hubble and James Web Telescope
| Hubble | James Web | | --- | --- | | 1990 | 2021 | | LEO 550 KM | L2 Lagrange Point | | UV & Visible | Infrared - It can see 150 Million KM farther than hubble | | Mirror 2.5 Mtr | Mirror 6.5 Mtr |
Engines
Principle on which Engine Works
To Produce Exahust Gases
Air Breathing Engines Because they use Air as a Oxidiser for Burning
ICE - Internal Combustion Engine
Basic Jet Engine
They are used in Aeroplanes and Missiles works on Newtons Third Law of Motion “Every Action has an Equal & Opposite Reaction”
Example : Walking, Rowing & Gun Recoil
Jet Engines the conventional ones use compressorary Blades (o2) to draw in Air and compress it - to increase the percentage of Oxygen per unit area
Mixture of fuel and air is burnt in the combustion chamber which produces hot exhaust gases, these hot exhaust gases are forced out of the exhaust nosel so the engine gets a forward thrust in oppoosite direction. this is essentially newtons third Law of Motion
Example : Used in Commercial Flights
Ramjet Engines - Variant of Basic Jet Engines
Ramjet Engine is a varaint of Jet Engine but it does not have any rotating parts, the forward speed of the vehicle is sufficient to compress the incoming air
Example of Usage are : Cruise Missiles → Brahmos
Ramjet Engines can be Sub Sonic
Scramjet Engines - Variant of Ramjet Engines
- It is a variant of Scramjet Engines
- It does not have any moving parts
- however the forward speed is at Supersonic Speed. So the air is compressed at a very fast rate
- Example : Cruise Missiles like Nirbhay
Rocket Engines
Liquid Rocket Engines
Single Stage Rocket
Since they will not get supply of air, rocket engine carries its own oxidiser. through pipes the fuel and the oxidiser are brought in the combustion chamber where they are burnt leading to production of huge amounts of exhaust gases
these exhaust gases are forced out of exhaust nozel producing thrust in opposite direction.
Cryogenic Engines
Liquification by Decreasing the Temperature to increase energy per unit volume to be very high
The Word Cryogenic has been derived from Greek Word Cryos meaning Frost and Genic means to Produce
In Science we refer Cryogenic as the Production and Effects of Very Low Temperature. Temperatures below -150 degree celsius. At Ceyogenic States volume of the gases reduces Drastically thus increasing the Energy Density.
Hydrogen Volume reduces by 600 times. Oxygens Volume also reduces drastically.
When Liquid oxidiser and fuel burns the combustion rate is drastically more compared to conventional rocket engines.
Only 6 countries have cryo capabilities - USA, Russia, China, France, Japan and India
Semi Cryogenic Engines
Fuel is Naturally Liquid. Here Only Oxidiser is in the Cryo State.
In Semi Cryogenic only one amongst the Two i.e Fuel or Oxidiser is in Cryogenic State
Fuel is Naturally Found in Liquid Form, like Kerosene but the Oxidiser is Liquid Oxygen
Indias First Private Cryogenic Engine known as Dhawan 1 by Skyroot Company
The fuel that it uses is Liquid Natural Gas and the Oxidiser is Liquid Oxygen → Here LNG is also taken to Cryo State
Launch Vehicles
Evolutionary Scheme of Launch Vehicles in India
Indian Launch Vehicles Chronology → SLV, ASLV, PSLV, GSLV (MK1, MK2, MK3)
Not in Evolutionary Scheme is SSLV
Meaning of Payload
Weight of the Satellite or the Object being carried
SLV - Satellite Launch Vehicle, 1979
- Started in 1979, was born out of need for Indigenous Satellite Launch Capacities
- It has a Payload Capacity of only 40 Kg in Low Earth Orbit
- It is out of Service and Syallbus as well
ASLV - Augmented Satellite Launch Vehicl, 1987
- It started in 1987
- It was born out of need to Increase the Payload Capacity
- Its Payload Capacity was 150 Kg in LEO (Low Earth Orbit)
- It is out of Service and Syallbus as well
PSLV - Polar Satelleite Launch Vehicle, 1994
It started in 1994
It was born out of need to have a versatile capacity
Its payload capacity was 1700 Kg in LEO and 1300 Kg in SSO
Can be sent to Geo Synchronous Orbit by using Transfer Orbit
PSLV has 4 stages with alterante stages of solid and liquid engines. The First stage is Solid Engine Base.
Payload Fairing → Provides Protection to the Satellite and Improves the Aerodynamic Capability of Launch Vehicle
Every Stage is connected to each other but Independent of Each Other.
Significance of PSLV
- It has become workhorse of ISRO - After its succesfull launch in 1994
- It sent 39 Consectuive Succesfull Flights till 2019
- It has sent more than 200 Foreign Satellites and more than 50 Indian Satellites
- It was also used in Sending Chandrayaan 1 Mission and also in Mangalyaan MoM 1 Mission
- Liquid Engine was used for the first time in PSLV
GSLV - Geosynchronous Satellite Launch Vehicle,
- It is the largest launch vehicle of India
- It has three stages
- Stage 1 - Solid
- Stage 2 - Liquid
- Stage 3 - Cryogenic Stage
- Its payload capacity is
- 10,000 Kg in LEO (GSLV Mak 3)
- 4000 Kg in GSO
- GSLV Mak 1,2,3 → The Only Difference is in Payload Capacity and the designs are same
Falcon - In the Same Lines of GSLV
- Falcon is the Launch Vehicle of SpaceX
- There are Two Types of Falcon
- Normal Falcon
- Falcon Heavy
- It has two stages, it is the worlds first Orbital Class Reusable Rocket
- Reusability allows Space X to Refly the most expensive parts of the Rocket. Thus Reducing the cost of Space Travel
Comparison of GSLV & Falcon
| Theme | GSLV | Falcon | | --- | --- | --- | | Stages | 3 | 2 | | No of Engines Per Stage | 1 Engines Per Stage | 10 Small Engine Per Stage | | Payload Capacity | 10,000 Kg in LEO | 64,000 Kg in LEO | | Cost Per Launch | 50 Million Dollars | 150 Million Dollars | | Per Unit Weight Wise | Falcon is more cost efficient | this is 3 times costlier but can carry weight 6 times heavier | | Reusability | It is NOT reusable | It is Reusable | | Success Rate | 100 Percent | 100 Percent | | Cost Efficiency | wrt to Cost Per Unit Weight Falcon is GSLV is costly | wrt to Cost Per Unit Weight Falcon is Falcon is Cheap |
Indias Pursuit of Reusable Launch Vehicle-Technology Demonstrator (RLV TD)
It is one of the most technologically challengin endeavours of ISRO, to develop essential technologies for a fully reusable launch vehicle
RLV TD has been configured to test critical technologies such as hypersonic flight, powered cruise flight and autonomus landing
Its design is a combination of a Rocket and Aeroplane
Rocket → Body
Wings → Aeroplane
SSLV - Small Satellite Launch Vehicle
- It is a special class of launch vehicles
- It can be configured it in 3 Days
- It is developed to cater launch on demand for small satellites in a cost effective manner
- Features of SSLV
- It has 3 stages - all solid
- Its payload capacity is 500 Kg * 500 Km LEO
- Or 300 Kg in SSO
- Configuration Time is only 72 Hours where as coneventional launch vehicles take only 72 days
- Significance of SSLV
- TAT - Turnaround Time - It helps in reducing the turnaround time
- It is cost effective - lowers the per kg launch cost
- it will increase the market share of ISRO in the commercial launch market
- It will help the ancillary industries, hecne they will need to ramp up the production
- It will increase the Presitge of India thus Increasing the Soft Power
- Why was it in News
The Second Flight of SSLV was a Succesfull Launch
Maiden flight experienced Failure
Isro said that the mission failed after the upper stage of the SSLV launch vehicle injected the satellites into a highly elliptical unstable orbit due to a shortfall in velocity, leading to their decay and deorbiting immediately, in spite of the normal performance of all solid propulsion stages.
The Reason Being
The Satellite was supposed to be sent in a circular orbit of radius 350 Km but mistakenly the satellite was sent not in a circular orbit having epogy as 350 km and perigy as 70 km
Hieght of Earths Atmosphere is 100 KM, So this Satellite Entered into Earths Atmosphere and Burnt Out
Difference Between PSLV and SSLV
ISS - International Space Station
Introduction & Details
Space Station is a Habitable Structure/Region in Space which is Artificially Created
International Space Station is a Collaboration of Many Space Agencies such as NASA, ESA, Roskomos, JAXA, CSA
It is the Largest Single Structure which humans have places in Space
It is placed in Low Earth Orbit at an Altitude of Around 400 KM and circles the Earth in Every 90 Minutes. It has a Micto Gravity Environment
It has been manned continuosly since Nov 2000. Till Now More than 250 Individuals have been to ISS
Significance of Space Station / ISS
- Because of Microgravity
- High Quality Protien Crystals can be manufactured without defects
- We can develop highly efficient vaccines in Micro Gravity
- We Can study bone related like Back Pain, Osteoporosis(reduced density of bones), Arthirits (Inflammation of Joints) Health Issues in Micro Gravity
- It will help in Commericalising Low Earth Orbit
- It will act as a Base for Further Space Missions
- It observes earth from a Vantage Point so we can monitor resources - water, mineral, fisihing resources, can monitor disasters etc
- Because of Microgravity
HW : What is Indias Plan to have its own Space Station and how will it benifit our space program
- Intro - Statement by ISRO Chief
- Feature of Indias Plan
- Benefits of Space Program
- Technical or Space Program
- Political
- Economic
- Other Benifits
- Challenges use Single Words → in Diagram Form
- Conclusion → R&D Percentage Increase, Course in University, Privitisation Entry in Space
Positoning & Navigations Systems (Global and Regional)
GPS - Global Positoning System
- It is a Network of 31 Satellites Orbiting the Earth
- It is also called as GPS Constellations
- Only 24 Satellites are used to gove accurate locations
- 8 Satellites are Spare Ones
- Each Satellite Orbits the Earth Twice a Day. The Orbit is NEO at an Altitude of 20,000 KM
- To find the Location or Positions of an Object only three satellites are needed at any particular time
- The Other Satellites helps in Improving Accuracy. The Accuracy of GPS is 7 Meteres 90 Percent of Time
- GPS Provides Two Types of Services
- Restrictive Services → For Armed Forces
- Stadnard Services → For Civilians
- It has very high accurate clocks known as atomic clocks
Glonass - Global Navigation System of Russia
- Its a Global Navigation System of Russia
- It has 31 Satellites and 24 are in Operation
Galileo - European Region
- Regional Navigational System proiing coverage in European Area
- It has 30 Satellites Placed in NEO
Baidu - China
- It will have 29 Satellites by 2030
- It has satellites in NEO Geo Synchronus and Geo Stationary
NAVIC - India
Historical Bkg - During 1999 Kargil War when pakistanis troops took high position in mountains, India wanted GPS Coordinates but USA denied
So a Need for Indigenous Naviagtion System was felt. Then Israel Helped India, thus the Cladenstine Secret Lov Affair of Indian and Israel became clear and visible after Kargil War
IRNSS - Indian Regional Navigation Satellite System was Developed. it is old name of NAVIC
It provides Coverage to whole of India and 1500 KM’s beyong its borders
At Present there are 7 Satellites in the System. The Plan is of 8 Satellites
They are placed in
- 3 Geo Stationary
- 4 Geo Synchronous
Provides Two Types of Services
- Standard Positioning System - To Civilians
- Restrcitive Services - For Authorised Personnels Only (Like Defence, Security Agencies)
Astrosat
Was Sent in 2015. Its weight is around 1500 KG. PSLV was used to Launch it
It is the first dedicated Indian Astronomy Mission aimed at studying celestial bodies in X Ray, UV and Optical Band (visible) simultaneously
Features
- Simulataneous Multi Wave Length Observation
- LEO at an Altitude of 650 KM
Objective
- To Observe High Energy Processes such as Merger of Neutron Star, Black Hole
- To Observe Magnetic Filed of Neutron Star
- To Study Star Birth Regions
Compartive Range of Study
Prelims PYQP
Answer is D
Generic Uses or Significance of this Navigation System
- For Terrestrial, Aeril and Marine Navigation
- Fleet Management - Vehicle Tracking and Monitoring
- Security and Border Area Management
- Disaster Management
- Forest Monitoring
- Precision Timing Services
- Resource Mapping
- Check on Border Areas
- Dynamic Handling of Traffic
- Better Policing
- Vehicle Tracking
- Regional Influence
- Strategic Autonomy
Prelims PYQP
Answer A - 1 Only
Answer B - 1 & 2 Only | 2 Needs to be taken care of
Mains PYQP
Question: Discuss Indias Achievement in the Field of Space Science and Tecnology. How the Application of this Technology has helped India in its socio economic development.
Answer Structure:
- Introductions
- From Aryabhatta to Modern IRSO
- Vikram Sarabhai - Father of Indian Space Program
- Achievement - Factual - Crisp and Short
- Socio Economic Development - Analytical Part - Elaborate and Argue → Sector Wise
- Agriculture
- Disaster
- Health
- Education
- Introductions
Beyond Solar System
Special Theory of Relativity
Einsteins Conception of Gravity is different from that of Newton, for this conception he talks about Space Time Matrix. Time depends on the space where measure it.
If time is ticking of clock then the clock ticks differently at different places in space, for example time ticks faster on moon as compared to earth. Time literally stops neat a Black Hole
Hence, we can say that time depends on gravity (more the gravity, slower the time)
Postulate 1 : Hence, Space and Time are interlinked and Interwoven, they form a Matrix. This matrix can be imagined as a big piece of cloth
Postulate 2 : Nothing cannot travel faster than speed of light
General Theory of Relativity
Introduction
In this einstein gives the conception of gravity in elaborate manner. So he says that matter Warps Space and Time. Heavier the Matter, More the Warping/Bending of Space & Time Matrix
According to Einstein, Gravity is not because of Force of Attraction, Gravity is Essentially because of the Curvature of Space Time Matrix
Planets are revolving because of the Warping of Space Time Matrix. Hence His Concept of Gravity is different from Newtons Theory of Gravity
In his theory of General Theory of Relativity, he gives the Theory of Black Holes, Singularity, Event Horizone, Worm Holes & Gravitational Waves
Concept of Big Bang Theory
Singularity
Singularity is essentialy the centre of a black hole. Scientist in an Attempt to find answer to the question that what existed before big bang came up with concept of Singularity
Einstein in his General Theory of Relativity before big bang there was singularity. Big Bang is Explosion of a Black Hole.
How did black hole existed is by God.
Event Horizon
Escape Velocity of Earth is 11.2 KM/Second
Escape Velocity for Black Hole is Greater than Speed of Light
It is an Area Aorund a Black Hole, where if Light Enters it cannot leave, the escape velocity needed to move out of its gravity is greater than speed of light but according to special theory of relativity, nothing can travel faster than speed of light. So even light gets trapped in this area
Avi Loeb, A Harvard Professor of Astonomy is, “Event Horizon is Ultimate Prison, One can get in but cannot get out”
Worm Holes
Worm Hole is a Bridge in Space Time Matrix, which acts as a Shortcut for Space Travel. This concept was given by Enistein in his General Theory of Relativity.
Later on Rosenburg Also Elaborated on this Concept, Hence they are also known Einstein Rosenburg Bridges. Wormholes are possible because of Bending of Space Time Matrix.
If the Space Time Matrix forms a C Type Loop, then you can get a Wormhole. Hence Time Travel is Possible through Worm Holes
Gravitational Waves
Introduction
Gravitational Waves are Ripples in Space Time Matrix Produced in Some of the most Cataclysmic Events such as Mergers of Black Holes, Neutron Stars.
These waves travel in Space, Time and Some of these waves can even reach earth. These Gravitational Waves have a Unique Property that they compress the matter in one direction and elongate the matter in aother direction
How is Gravitational Wave Detected ?
LIGO - On Earth
Gravitational Waves is Detected by using a Property of Light called as Interference. The device used is called LIGO.
Two Arms are constructed at 90 Degrees having the same exact length. A Laser light is sent in both the arms at the same time, light takes the same time to travel both the arms.
So At Point O, No Time Difference is Recorded but when a Gravitational Wave or a G Wave Hits the System. One of the Arms gets compressed and other arms elongates and now some time difference is observed at O
LIGO is : “Laser Interferrometere Gravitational Wave Observatory”
It is a Earth Based G Wave Detector, the Arms have a Length of 4 KM. LIGO has detected Mergers of Black Holes
LISA - In Space
Answer is B
LISA is Laser Interferometer Space Antenna
It is a Space Based Gravitational Wave Observatory. LISA is placed at Lagrange Point L1. It also uses the principles of Interference of Light to detect G Waves
E-LISA - In Space
It is Evolved LISA
It is a future endevaour to detect gravitational waves. It is also space based observatory, it will have three space crafts in traingular pattern, having a distance of One Million KM between them
Prelims PYQP
Answer is D
Issues
- Space Weaponisation
- Space Debris
- Space Privatisation
All Space Missions by ISRO
Aditya L1 - Mercury
- ISRO is preparing for its scientific expedition to Sun. It will be placed in Lagrange Point L1 where it will get uninterrupted view of the Sun and also less fuel will be required
- Its objective is to study corona, chromosphere, photosphere and solar winds. Essentially its interested in studying the Outer Layer
Shukryaan - Venus
- India’s Mission to be Launched in December 2024
- Its an Orbiter Type Mission
Chandrayaan 1 - Moon
- It was sent in 2009
- It was India’s first Lunar Mission
- One of the Significant Findings of Chandrayaan 1 was presence of water on Surface of Moon
Chandrayaan 2 - Moon
- Sent in 2019
- Launched by PSLV
- Consisted of Orbiter, Lander or Rover all developed in India
- The Lander was called Vikram and it crash landed during the final phase of descent
Chandrayaan 3 - Moon
It is mission repeat of Chandrayaan 2, it will also have a lander rover and a propulsion module to attempt soft landing
Mangalyan MoM 1 (India) - Mars
- Sent in 2014
- Orbiter Type of Mission
- India’s First Inter Planetary Mission
- ISRO became the fourth agency to reach Mars (First Three - NASA, ESA, Roscomos)
- India became the first asian nations, first nation to do it in first attempt
Mangalyaan MoM 2 (India) - Mars
- Will be second interplanetary mission planned for launch in Near Future
- Will Consist of Orbiter, Lander, and Rover