What is master of the roaster? 

To sum it up in simple terms, it means the head of the administrative side. Be it the Chief Justice of India or Chief Justice of any high court it is he or she who heads the administrative side. This includes allocation of matters before a judge as well.

The power to allocate matters before a Bench or judge is the power that the CJI or CJs have got and it cannot be overridden by a judicial order even if the CJI or CJ is sitting on a Constitution Bench.

CURRENT ISSUE:- 

The administrative powers are taken over by the senior most judge of a Supreme Court or High Court only if the CJI/CJ is on leave. In this case, the problem began when a Bench headed by Justice Chelameswar ordered that a case is heard by five senior-most judges of the Supreme Court.

Senior advocate, K N Phanindra tells that this order itself was wrong. Following this order, the same was overturned by the CJI saying that only he could allocate the Bench as he was the master of the roaster.

Phanindra further states that the CJ being the master of the roaster is a well-accepted norm and convention. Justice Chelameswar ought to have placed the matter before the CJI to be allocated before a suitable Bench. He could not have said that by himself by way of a judicial order. Even in cases where there are divergent views, it is the CJ who takes the final call on who the third judge would be.
In my view this whole concept of a junior and senior judge in the Supreme Court itself is wrong. The CJI is the senior most among equals is what the norm and convention are, Phanindra also points out.

The Cauvery Water Disputes Tribunal (CWDT) Prescriptions on resolving Cauvery Water Dispute:-

• The CWDT had prescribed the setting up of a Cauvery Management Board(CMB) and
• The Cauvery Water RegulationCommittee (CWRC)  to monitor the implementation of its order.
• The CMB ought to be headed by a Chief Engineer with at least 20 years of experience. 
•  The CMB would monitor the storage position in the Cauvery basin and the trend of rainfall, to assess the likely inflows for distribution among the States. 
• The CWRC will ensure the Tribunal’s order is carried out.
• The CMB envisaged three full­time members including a chairman.
  It was also to consist of six part­time members, four of whom will be from the riparian States of Karnataka,Kerala, Tamil Nadu, and the Union Territory of Puducherry
   

 

           How Do Satellites Work?

Google Earth provides you the opportunity to visit any place on Earth, yet what do most people do? Look at their own house. In fact, Google Earth doesn’t just show you high-resolution pictures; like Scrooge on one of his ghosts, you are practically tossed there, as you can witness walking pedestrians and live traffic! But how does Google Earth achieve this feat?

With satellites!

What is a Satellite?

The word satellite doesn’t necessarily describe a mechanical box floating through space with solar panels attached to either sides. In more general terms, a satellite is any space-based object that orbits a planet. For instance, the moon is a natural satellite, whereas satellites launched to propagate communication and navigate are artificial, man-made satellites.

To place a satellite in a stable orbit around Earth, it needs to overcome Earth’s gravitational pull and air resistance in its lower atmosphere. The velocity at which it escapes this pull is the escape velocity, which is around 7 miles per second. Even after escaping Earth, a satellite’s tendency to remain in its orbit is contested by the Earth’s constant pull of gravity.

Its linear velocity pushes it outward, while gravity pulls it inward towards the planet. The satellite eventually settles in an orbit when these forces are balanced.

The velocity to keep a satellite in orbit is much higher, and is known as the orbital speed, which is around 17,000 miles per hour.

  
A satellite doesn't necessarily have to be a tin can spinning through space. The word "satellite" is more general than that: it means a smaller, space-based object moving in a loop (an orbit) around a larger object. The Moon is a natural satellite of Earth, for example, because gravity locks it in orbit around our planet. The tin cans we think of as satellites are actually artificial (human-built) satellites that move in precisely calculated paths, circular or elliptical (oval), at various distances from Earth, usually well outside its atmosphere.

We put satellites in space to overcome the various limitations of Earth's geography—it helps us step outside our Earth-bound lives. If you want to make a phone call from the North Pole, you can fire a signal into space and back down again, using a communications satellite as a mirror to bounce the signal back to Earth and its destination. If you want to survey crops or ocean temperatures, you could do it from a plane, but a satellite can capture more data more quickly because it's higher up and further away. Similarly, if you want to drive somewhere you've never been before, you could study maps or ask random strangers for directions, or you could use signals from satellites to guide you instead. Satellites, in short, help us live within Earth's limits precisely because they themselves sit outside them.

What do satellites do for us?

We tend to group satellites either according to the jobs they do or the orbits they follow. These two things are, however, very closely related, because the job a satellite does usually determines both how far away from Earth it needs to be, how fast it has to move, and the orbit it has to follow. The three main uses of satellites are for communications; photography, imaging, and scientific surveying; and navigation.

  

Communications

Communications satellites are essentially used to relay radio waves from one place on Earth to another, catching signals that fire up to them from a ground station (an Earth-based satellite dish), amplifying them so they have enough strength to continue (and modifying them in other ways), and then bouncing them back down to a second ground station somewhere else. Those signals can carry anything radio signals can carry on the ground, from telephone calls and Internet data to radio and TV broadcasts. Communications satellites essentially overcome the problem of sending radio waves, which shoot in straight lines, around our curved planet—intercontinental signals, in other words. They're also useful for communicating to and from remote areas where ordinary wired or wireless communications can't reach. Calling with a traditional landline (wired phone), you need a very convoluted network of wires and exchanges to make a complete physical circuit all the way from the sender to the receiver; with a cellphone, you can communicate anywhere you can get a signal, but you and the receiver both still need to be within range of cellphone masts; however, with a satellite phone, you can be on top of Mount Everest or deep in the Amazon jungle. You're entirely free from any kind of telecommunications "infrastructure," which gives you geographic freedom and an instant ability to communicate (you don't have to wait for someone to string up telephone lines or set up cellphone masts).

The best known modern communications satellite systems are probably INMARSAT and INTELSAT. INMARSAT was originally a satellite system for ships, planes, and other travelers, though it now has many other uses as well. INTELSAT is an international consortium that owns and operates several dozen communications satellites that provide things like international broadcasting and satellite broadband Internet.

Photography, imaging, and scientific surveying

Photo: Satellite photography has revolutionized map-making. This is Havana, Cuba photographed by the Landsat satellite. Picture courtesy of NASA Landsat program.

Not so many years ago, newspapers used to run scare stories about spy satellites high in space that could read newspapers over your shoulder. These days, we all have access to satellite photos, albeit not quite that detailed: they're built into search engines like Google and Bing, and they feature routinely on the news (giving us an instant visual impression of things like disappearing rainforests or tsunami destruction) and weather forecasts. Scientific satellites work in a similar way to photographic ones but, instead of capturing simple visual images, systematically gather other kinds of data over vast areas of the globe.

There have been many interesting scientific satellite missions over the last few decades. NASA's TOPEX/Poseidon and Jason satellites, for example, have routinely measured sea levels since the early 1990s. SeaWiFS (active until 2010) scanned the color of the ocean to measure plankton and nutritional activity in the sea. As its name suggests, a weather satellite called TRMM (Tropical Rainfall Measuring Mission) monitored rain near the equator from 1997 through 2015. As of 2016, NASA listed 25 ongoing satellite missions on its website, including CALIPSO (which studies how clouds and aerosols interact); Nimbus (a long-running scientific study of weather and climate using satellite data); and, the longest-running and perhaps best known scientific satellites of all-time, Landsat, a series of eight satellites that have been continuously mapping and monitoring changes in land use across Earth since 1972.

Navigation

Finally, most of us with GPS-enabled cellphones and "sat-nav" devices in our cars are familiar with the way satellites act like sky compasses; you'll find GPS, Glonass, and similar systems discussed in much more detail in our article about satellite navigation.

How do communications satellites work?

What do they do?

Communications satellites are "space mirrors" that can help us bounce radio, TV, Internet data, and other kinds of information from one side of Earth to the other.

Uplinks and downlinks

If you want to send something like a TV broadcast from one side of Earth to the other, there are three stages involved. First, there's the uplink, where data is beamed up to the satellite from a ground station on Earth. Next, the satellite processes the data using a number of onboard transponders(radio receivers, amplifiers, and transmitters). These boost the incoming signals and change their frequency, so incoming signals don't get confused with outgoing ones. Different transponders in the same satellite are used to handle different TV stations carried on different frequencies. Finally, there's the downlink, where data is sent back down to another ground station elsewhere on Earth. Although there's usually just a single uplink, there may be millions of downlinks, for example, if many people are receiving the same satellite TV signal at once. While a communications satellite might relay a signal between one sender and receiver (fired up into space and back down again, with one uplink and one downlink), satellite broadcasts typically involve one or more uplinks (for one or more TV channels) and multiple downlinks (to ground stations or individual satellite TV subscribers).

 Satellites are like any other vehicle inasmuch as they have two main parts: the generic vehicle itself and the specific thing it carries (the payload) to do its unique job. The "vehicle" part of a satellite is called the bus, and it includes the outer case, the solar panels and batteries that provide power, telemetry (a remote-controlled system that sends monitoring data from the satellite to Earth and operational commands back in the other direction), rocket thrusters to keep it in position, and reflective materials or other systems ("heat pipes") to protect it from solar radiation and dissipate heat. The payload might include transponders for a communications satellite, computers and atomic clocks to generate time signals for a navigation satellite, cameras and computers to images back to digital data for a photographic satellite, and so on.

What's inside a satellite?(Anatomy of a satellite)

Artwork: Communications satellite. From US Patent: #3,559,919: Active communication satellite, courtesy of US Patent and Trademark Office.

These are amazingly complex and expensive machines with tons of electronic bits and pieces jammed into them, but let's not get too bogged down in the details: the basic idea is very simple. In this outside view of a typical satellite, from a patent filed in 1968 by German engineer Hans Sass (US Patent: #3,559,919: Active communication satellite), you can see all the main bits and it's easy to figure out what they do.

I've left the original numbers on the diagram and I won't bother to label them all, since some are obvious and some are duplicates of others. The most interesting bits are the fold-out solar panels that power the satellite, the sending and receiving antennas that collect signals coming up from Earth and send them back down, and the motors and engines that keep the satellite in exactly the right position at all times:

4: Large parabolic dish antenna for sending/receiving signals. (Orange)

5: Small parabolic dish antenna for sending/receiving signals. (Orange)

6: Lower solar "battery" of four solar panels. (Red)

7: Upper solar "battery" of four more solar panels. (Red)

8: Supports fold out the lower solar panels once the satellite is in orbit. (Gray-brown)

9: Supports fold out the upper solar panels. (Gray-brown)

10: Main satellite rocket motor. (Light blue)

11, 12, 15, 17: Small control engines keep the satellite in its precision position, spin, and orbit. (Green)

Satellite orbits

Artificial satellites in orbit around the Earth have different orbits. Satellites in lower orbits travel faster than those in higher orbits. The higher the orbit of a satellite, the longer its 'period' (time to make one orbit).

One of the most surprising things about satellites is the very different paths they follow at very different heights above Earth. Left to its own devices, a satellite fired into space might fall back to Earth just like a stone tossed into the air. To stop that happening, satellites have to keep moving all the time so, even though the force of gravity is pulling on them, they never actually crash back to Earth. Some turn at the same rotational rate as Earth so they're effectively fixed in one position above our heads; others go much faster. Although there are many different types of satellite orbits, they come in three basic varieties, low, medium, and high—which are short, medium, and long distances above Earth, respectively.

Low-Earth orbits

Scientific satellites tend to be quite close to Earth—often just a few hundred kilometers up—and follow an almost circular path called a low-Earth orbit (LEO). Since they have to be moving very fast to overcome Earth's gravity, and they have a relatively small orbit (because they're so close), they cover large areas of the planet quite quickly and never stay over one part of Earth for more than a few minutes. Some follow what's called a polar orbit, passing over both the North and South poles in a "loop" taking just over an hour and a half to complete.

Medium-earth orbits

The higher up a satellite is, the longer it spends over any one part of Earth. It's just the same as jet planes flying over your head: the slower they move through the sky, the higher up they are. A medium-Earth orbit (MEO) is about 10 times higher up than a LEO. GPS navstar satellites are in MEO orbits roughly 20,000 km (12,000 miles) above our heads and take 12 hours to "loop" the planet. Their orbits are semi-synchronous, which means that, while they're not always exactly in the same place above our heads, they pass above the same points on the equator at the same times each day.

High-Earth orbits

Many satellites have orbits at a carefully chosen distance of about 36,000 km (22,000 miles) from the surface. This "magic" position ensures they take exactly one day to orbit Earth and always return to the same position above it, at the same time of day. A high-Earth orbit like this is called geosynchronous (because it's synchronized with Earth's rotation) or geostationary (if the satellite stays over the same point on Earth all the time).Communications satellites—our "space mirrors"—are usually parked in geostationary orbits so their signals always reach the satellite dishes pointing up at them. Weather satellites often use geostationary orbits because they need to keep gathering cloud or rainfall images from the same broad part of Earth from hour to hour and day to day (unlike LEO scientific satellites, which gather data from many different places over a relatively short period of time, geostationary weather satellites gather their data from a smaller area over a longer period of time).

Who invented satellites?

Artwork: Soviet engineers were the first to build a working satellite, Sputnik, and put it into space in 1957. Stamps like this celebrated that stunning achievement. Artwork believed to be in the public domain, courtesy of Wikimedia Commons.

The idea of using a satellite as a mirror in space—to bounce signals from one side of Earth to the other—was "launched" in 1945 by science fiction author Arthur C. Clarke (1917–2008), who wrote two hugely influential articles setting out his plan in detail (one was unpublished, the other published as "Extra-Terrestrial Relays: Can Rocket Stations Give World-Wide Radio Coverage?" in Wireless World, October 1945). His proposal was to place three satellites in a geosynchronous orbit 35,000km (23,000 miles) above Earth, spaced out evenly to cover about a third of the planet each: one would cover Africa and Europe, a second would cover China and Asia, and a third would be dedicated to the Americas. Although Clarke didn't patent the geostationary communications satellite, he is generally credited with its invention, even though other space pioneers (notably German wartime pioneer Herman Oberth) had proposed similar ideas years before.

Photo: Echoes of history: Designed by NASA, the Echo communications satellite was a giant mylar balloon some 30m (100ft) in diameter designed to sit in space and bounce signals back like a mirror. You can see how big it is from the size of the car and people at the bottom, which I've colored red to help you pick them out. Picture courtesy of NASA on The Commons.

It took another decade for Clarke's bold plan to move toward reality. First, satellites themselves had to be proved viable; that happened with the launch of the Russian Sputnik 1 in October 1957. Three years later, when the Echo communications satellite was launched, engineers successfully demonstrated that radio telecommunications signals could be relayed into space and back, just as Clarke had predicted. Telstar, the first communications satellite, was launched in July 1962 and immediately revolutionized transatlantic telecommunications. During the mid-1960s, 11 nations came together to form INTELSAT (International Telecommunications Satellite Consortium), which launched the world's first commercial communications satellite INTELSAT 1 ("Early Bird"), in geosychronous orbit, in April 1965. This modest little space machine was a tiny electronic miracle: weighing just 35kg (76 lb), it could transmit 240 telephone simultaneous calls or a single black-and-white TV channel.

 

Satellites come in two types:

1.Polar: These satellites hover over the poles and monitor the Earth while it rotates continuously beneath them, so that eventually the entire Earth is subject to their scrutiny, as they remain in the same place.  

A polar orbiting satellite closely parallels the earth's meridian lines, thus having a highly inclined orbit close to 90°. It passes over the north and south poles each revolution.They orbit between 100 km and 200 km above the Earth’s surface. As the earth rotates to the east beneath the satellite, each pass monitors an area to the west of the previous pass at intervals of roughly 90 to 100 minutes ,so the satellite can scan the whole surface of the Earth. These strips can be pieced together to produce a picture of a larger area. 
 
Uses: monitoring the weather, observing the Earth’s surface, military uses including spying
Advantage:  Polar satellites have the advantage of photographing clouds directly beneath them. They also circle at a much lower altitude (about 850 km) providing more detailed information about violent storms and cloud systems. 




2.Geosynchronous or Geostationary: These are attached to a particular location, as their rotation is synchronized with the Earth’s rotation. These are used to monitor or communicate with the receivers in a particular location. 

Geostationary satellites have a different trajectory to polar satellites – they are in orbit above the equator. The height of their orbit - 36,000 km(approximately 35,800 kilometers directly over the equator) - is just the right distance so that it takes them one day (24 hours) to make each orbit.  It revolves in the same direction the earth rotates (west to east).This means that they stay in a fixed position over the Earth’s surface. Geostationary satellites have uses such as:


Uses: Direct broadcast TV, Communication network including satellite TV, Defence and intelligence, global positioning or GPS - which is used for satellite navigation systems


Advantage: Geostationary satellites remains in the same position throughout the day when seen from the ground, and this is why satellite television dishes can be bolted into one position  directed towards the satellite  remain on track and do not need to move.

 

 

Attitude control

• Satellites must take precise measurements from their place in orbit without wobbling. This is why they are regularly stabilized, which is called attitude control.
• Gyroscopic motion is utilized to stabilize the position of a satellite’s cameras and its orientation in space with respect to the object that it’s orbiting.
• Without stabilization, a satellite might deviate from its path outward to space or towards the Earth, providing inaccurate results and rendering it unreliable.
• Gyroscopes rotate up to 6,000 RPM for three-axis stabilization and around 60-70 RPM for a spin-stabilized cylindrical satellite. 

Body or Bus

The body of a satellite houses the necessary scientific equipment it possesses. It is designed specifically to carry them safely into space. Engineers must consider a number of different objectives while designing and developing the body.

• The outer layer protects it from space particles or micrometeorites floating in space.
• Anti-radiation materials that protect it from the Sun’s harmful UV radiation.
• The satellite must sustain a comfortable temperature for proper functioning and must conduct heat away from its equipment.
• Structures to support and connect materials.
• Another major factor is economics. Its development should be economical, as in, cost-effective regarding its expenditure, longevity and weight.

Communication

The circuits responsible for communication are known as the satellite’s transponders. A satellite communicates by either transmitting or receiving signals.

Transmitter

The transmitter is a combination of many individual circuits.

1. Power supply: To provide constant power to all the circuits in a transmitter for their functioning.
2. Oscillator: The oscillator circuit generates a radio frequency signal, which is a sine wave of constant amplitude. This wave is known as the carrier, as it is later combined with the information to be transmitted and literally carries it on itself.
3. Modulator: This circuit combines the carrier with the information to be transmitted by varying some parameter of the carrier, such as its amplitude or frequency.
4. Amplifier: Satellites also use amplifiers to amplify a weakened signal and retransmit it to other satellites.
5. Antenna: Finally, this amplified signal is passed to the antenna, which uses reflectors to spew and radiate the signal as radio waves towards the receiver.

Receiver

The receiver intercepts the transmitted EM wave and extracts the information inside it to be used. The receiver consists of circuits that mirror a transmitter’s individual circuits.

1. Antenna: The antenna converges the radio waves through a reflector. The waves are further converged by foci, passing through twists and turns to finally reach the circuits where they are processed.
2. Amplifier: As the signal travels through a medium, some of its energy is attenuated, which is why it’s amplified again at the receiver’s end.
3. Tuner: The receiver receives multiple signals on a variety of frequencies from different transmitters. A tuner is used to listen to a particular signal that you want to hear.
4. Detect: The receiver then demodulates the signal or extracts the required information from the carrier signal.
5. Amplifier: The information is amplified again at the end to strengthen it and make sure it’s delivered with sufficient power.  
   

Power source

A satellite needs to operate 365 days a year, 24/7, revolving and collecting data. The most readily available source for power is the Sun, but even the Sun is screened by the Earth during eclipses. This is why solar cells are accompanied by high-performance batteries.

Command and Control Systems

This is the brain of the satellite, and includes the Tracking, Telemetry and Control (TT&C) system, which monitors and controls all of the satellite’s parameters, stores and analyses all the data, and governs its communication with one or more satellites.

The data consists of scientific information or telecommunication signals, as well as the satellite’s position and health information

How does it communicate?

Communication doesn’t necessarily have to occur in the Radio spectrum. Your TV remote communicates with its set top box with infrared waves, while phones communicate with microwaves. The selection of a particular portion of the electromagnetic spectrum depends on many factors, such as the size of antennae, distance between the two participating devices and the obstacles between them.

Waves undergo a phenomenon called diffraction, which makes them deviate and travel around an obstacle. Diffraction can only take place if a wave’s wavelength is comparable to the obstacle’s size. The large wavelengths of radio waves allow them to be easily diffracted around buildings and mountains.

Radio waves transmitted by satellites are also reflected by the charged particles of the ionosphere. This is extremely useful when two satellites on Earth need to communicate, but are not directly in line due to the Earth’s curvature. The transmitting antenna projects the waves at particular angles of incidence such that they are reflected by the ionosphere in the direction of the receiver. 

Satellites can also communicate with the help of a space satellite. Satellites hanging in space behave like a mirror, deflecting signals in the direction of the satellite receiving it. Space satellites not only reflect signals, but amplify and re-transmit them, as they are weakened due to constant dissipation in the medium and absorption by the atmosphere.

Bandwidth and Transmission

The radio spectrum comprises a range of frequencies on which information can travel. However, communication only occurs on specific frequencies set by The International Telecommunication Union based in Geneva, Switzerland. The frequencies are grouped together to form bandwidths. They can either be Narrow-band signals (kHz), which are used for limited services, such as paging and low-data communication, or Broadband signals (MHz), which are used for advanced communication, such as video transmission.

 Transmission from a station on Earth to a satellite in space is called an uplink. The satellite then amplifies it and reroutes this signal – on a different frequency – back to the Earth to one or more receivers. This is called a downlink. The area covered by the radiation on Earth is called its footprint.

Satellites are extremely useful devices that help us comprehend the incomprehensible geography of our planet. Although satellites have lately gotten a bad reputation, as they allow nosy tech-giant advertising corporations and security organizations to keep us under constant surveillance and disrespect our privacy, they still connect us to people across the globe through our phone or computer screens, and help us reach those people by navigating us one turn at a time.