Chandrayaan-1: Mission Definition and Goal
Chardrayaan-1 is the first Indian Mission to the Moon devoted to high-resolution remote sensing of the lunar surface features in visible, near infrared, X-ray and low energy gamma ray regions. This will be accomplished using several payloads already selected for the mission. In addition a total of about 10 kg payload weight and 10 W power are earmarked for proposals, which are now solicited. The mission is proposed to be a lunar polar orbiter at an altitude of about 100 km and is planned to be launched by 2007-2008 using indigenous spacecraft and launch vehicle of ISRO. The mission is expected to have an operational life of about 2 years.
Mission Objectives
* Carry out high resolution mapping of topographic features in 3D, distribution of various minerals and elemental chemical species including radioactive nuclides covering the entire lunar surface using a set of remote sensing payloads. The new set of data would help in unravelling mysteries about the origin and evolution of solar system in general and that of the moon in particular.
* Realize the mission goal of harnessing the science payloads, lunar craft and the launch vehicle with suitable ground support system including DSN station, integration and testing, launching and achieving lunar orbit of ~100 km, in-orbit operation of experiments, communication/telecommand, telemetry data reception, quick look data and archival for scientific utilization by identified group of scientists.
Specific areas of study
* High resolution mineralogical and chemical imaging of permanently shadowed north and south polar regions
* Search for surface or sub-surface water-ice on the moon, specially at lunar pole
* Identification of chemical end members of lunar high land rocks
* Chemical stratigraphy of lunar crust by remote sensing of central upland of large lunar craters, South Pole Aitken Region (SPAR) etc., where interior material may be expected
* To map the height variation of the lunar surface features along the satellite track
* Observation of X-ray spectrum greater than 10 keV and stereographic coverage of most of the moon's surface with 5 m resolution, to provide new insights in understanding the moon's origin and evolution
For more about CHANDRAYAAN - 1 Download this Article
courtesy: ISRO
What will happen on December 21, 2012? How the world is getting ready for that day?
The Mayan civilization predicted that on December 21, 2012 something will happen to the world we know. Something will happen that will change our civilization, value systems and the way we know human civilization forever.
What does that means? What did the Mayan see through their spiritual wisdom?
According to scientists and technologists something strange is happening behind the scene. The terrestrial and solar polar reversal peaks are coming within three weeks of that day, December 21, 2012. Innumerable UFOs are scouting our skies regularly and increasing as we approach that day. The tectonic plate shifts, underwater volcanoes, earthquakes, landslides and Tsunamis are increasing at rates never seen before. The solar flares are increasing. The earth’s magnetosphere and ionosphere are experiencing strange disturbances. The numbers of typhoons and cyclones have increased many folds. The number of floods and droughts has increased beyond imaginations in the last ten years.
Scientists who look beyond conventional science point out that that the Hyperspace that contain our Universe is also showing signs that something strange is happening in our universe. The multidimensional time research is showing that a parallel universe may be predicting strange effects.
According to some scientists it is possible that another Universe is slowly starting to claim a spatial dimension in our physical Universe. It is also possible that we will face major calamities because of the polar reversal in the Sun and in Earth. If that happens, it is possible that the hyperspace has to adjust the suction force known as gravity and Electromagnetic force fields to keep the earth and the solar system intact.
The biggest clue to what will happen comes from astrophysicists. There is a big possibility that the simultaneous polar reversal in earth and sun will throw the solar system out of whack. That will cause massive upheaval in the earth. At that point of time, the extraterrestrials will officially show up and put “cosmic seat belts” around us as they apply the superpower of the Hyperspace to bring the solar system back to what it is today.
According to think tanks, this has happened before. The extraterrestrials take care of the earth and the solar system whenever the solar system faces challenges like that.
What does that means? What did the Mayan see through their spiritual wisdom?
According to scientists and technologists something strange is happening behind the scene. The terrestrial and solar polar reversal peaks are coming within three weeks of that day, December 21, 2012. Innumerable UFOs are scouting our skies regularly and increasing as we approach that day. The tectonic plate shifts, underwater volcanoes, earthquakes, landslides and Tsunamis are increasing at rates never seen before. The solar flares are increasing. The earth’s magnetosphere and ionosphere are experiencing strange disturbances. The numbers of typhoons and cyclones have increased many folds. The number of floods and droughts has increased beyond imaginations in the last ten years.
Scientists who look beyond conventional science point out that that the Hyperspace that contain our Universe is also showing signs that something strange is happening in our universe. The multidimensional time research is showing that a parallel universe may be predicting strange effects.
According to some scientists it is possible that another Universe is slowly starting to claim a spatial dimension in our physical Universe. It is also possible that we will face major calamities because of the polar reversal in the Sun and in Earth. If that happens, it is possible that the hyperspace has to adjust the suction force known as gravity and Electromagnetic force fields to keep the earth and the solar system intact.
The biggest clue to what will happen comes from astrophysicists. There is a big possibility that the simultaneous polar reversal in earth and sun will throw the solar system out of whack. That will cause massive upheaval in the earth. At that point of time, the extraterrestrials will officially show up and put “cosmic seat belts” around us as they apply the superpower of the Hyperspace to bring the solar system back to what it is today.
According to think tanks, this has happened before. The extraterrestrials take care of the earth and the solar system whenever the solar system faces challenges like that.
Microwaves
Microwaves are electromagnetic waves with wavelengths ranging from 1 mm to 1 m, or frequencies between 0.3 GHz and 300 GHz.The microwave range includes ultra-high frequency (UHF) (0.3–3 GHz), super high frequency (SHF) (3–30 GHz), and extremely high frequency (EHF) (30–300 GHz) signals.
Apparatus and techniques may be described qualitatively as "microwave" when the wavelengths of signals are roughly the same as the dimensions of the equipment, so that lumped-element circuit theory is inaccurate. As a consequence, practical microwave technique tends to move away from the discrete resistors, capacitors, and inductors used with lower frequency radio waves. Instead, distributed circuit elements and transmission-line theory are more useful methods for design, analysis. Open-wire and coaxial transmission lines give way to waveguides, and lumped-element tuned circuits are replaced by cavity resonators or resonant lines. Effects of reflection, polarization, scattering, diffraction, and atmospheric absorption usually associated with visible light are of practical significance in the study of microwave propagation. The same equations of electromagnetic theory apply at all frequencies.
Applications of Microwaves.
Communication
Remote Sensing
Navigation
Power
Health effects
Apparatus and techniques may be described qualitatively as "microwave" when the wavelengths of signals are roughly the same as the dimensions of the equipment, so that lumped-element circuit theory is inaccurate. As a consequence, practical microwave technique tends to move away from the discrete resistors, capacitors, and inductors used with lower frequency radio waves. Instead, distributed circuit elements and transmission-line theory are more useful methods for design, analysis. Open-wire and coaxial transmission lines give way to waveguides, and lumped-element tuned circuits are replaced by cavity resonators or resonant lines. Effects of reflection, polarization, scattering, diffraction, and atmospheric absorption usually associated with visible light are of practical significance in the study of microwave propagation. The same equations of electromagnetic theory apply at all frequencies.
Applications of Microwaves.
Communication
- Before the advent of fiber optic transmission, most long distance telephone calls were carried via microwave point-to-point links through sites like the AT&T Long Lines.
- Wireless LAN protocols, such as Bluetooth and the IEEE 802.11 specifications, also use microwaves in the 2.4 GHz ISM band, although 802.11a uses ISM band and U-NII frequencies in the 5 GHz range.
- Metropolitan Area Networks: MAN protocols, such as WiMAX (Worldwide Interoperability for Microwave Access) based in the IEEE 802.16 specification.
- Wide Area Mobile Broadband Wireless Access: MBWA protocols based on standards specifications such as IEEE 802.20 or ATIS/ANSI HC-SDMA (e.g. iBurst) are designed to operate between 1.6 and 2.3 GHz to give mobility and in-building penetration characteristics similar to mobile phones but with vastly greater spectral efficiency.
- Cable TV and Internet access on coaxial cable as well as broadcast television use some of the lower microwave frequencies. Some mobile phone networks, like GSM, also use the lower microwave frequencies.
- Microwave radio is used in broadcasting and telecommunication transmissions because, due to their short wavelength, highly directive antennas are smaller and therefore more practical than they would be at longer wavelengths (lower frequencies).
Remote Sensing
- Radar uses microwave radiation to detect the range, speed, and other characteristics of remote objects. Development of radar was accelerated during World War II due to its great military utility. Now radar is widely used for applications such as air traffic control, navigation of ships, and speed limit enforcement.
- A Gunn diode oscillator and waveguide are used as a motion detector for automatic door openers (although these are being replaced by ultrasonic devices).
- Most radio astronomy uses microwaves.
- Microwave imaging; see Photoacoustic imaging in biomedicine
Navigation
- Global Navigation Satellite Systems (GNSS), the American Global Positioning System (GPS) and the (GLONASS) broadcast navigational signals in various bands between about 1.2 GHz and 1.6 GHz.
Power
- A microwave oven passes (non-ionizing) microwave radiation (at a frequency near 2.45 GHz) through food, causing dielectric heating by absorption of energy in the water, fats and sugar contained in the food
- Microwave heating is used in industrial processes for drying and curing products.
Health effects
- Microwaves contain insufficient energy to directly chemically change substances by ionization, and so are an example of nonionizing radiation.
Introduction to LiDAR Mapping
LiDAR is an acronym for Light Detection And Ranging, sometimes also referred to as Laser Altimetry or Airborne Laser Terrain Mapping (ALTM). The LiDAR system basically consists of integration of three technologies, namely, Inertial Navigation System (INS), LASER, and GPS. The Global Positioning System (GPS) has been fully operational for over a decade, and during this period, the technology has proved its potential in various application areas. Some of the important applications of GPS are crustal deformation studies, vehicle guidance systems, and more recently, in LiDAR.
Geo Spatial Information is an important input for all planning and developmental activities especially in the present era of digital mapping and decision support systems. LiDAR is much faster than conventional photogrammetric technology and offers distinct advantage over photogrammetry in some application areas. Its development goes back to 1970s and 1980s, with the introduction of the early NASA-LiDAR systems, and other attempts in USA and Canada (Ackermann, 1999). The method has successfully established itself as an important data collection technique, within a few years, and quickly spread into practical applications. Early 1980's, second generation LiDAR systems were in use around the world but were expensive and had limited capability. With the enhanced computer power available today, and with the latest positioning and orientation systems, LiDAR systems have become a commercially viable alternative for development of Digital Elevation Models (DEM) of earth surface.
Geo Spatial Information is an important input for all planning and developmental activities especially in the present era of digital mapping and decision support systems. LiDAR is much faster than conventional photogrammetric technology and offers distinct advantage over photogrammetry in some application areas. Its development goes back to 1970s and 1980s, with the introduction of the early NASA-LiDAR systems, and other attempts in USA and Canada (Ackermann, 1999). The method has successfully established itself as an important data collection technique, within a few years, and quickly spread into practical applications. Early 1980's, second generation LiDAR systems were in use around the world but were expensive and had limited capability. With the enhanced computer power available today, and with the latest positioning and orientation systems, LiDAR systems have become a commercially viable alternative for development of Digital Elevation Models (DEM) of earth surface.
What can you do with LIDAR?
- Measure distance,
- Measure speed,
- Measure rotation,
- Measure chemical composition and concentration.,
SOCET SET Tutorial
SOCET SET is a software application that performs a variety of functions related to photogrammetry. It is developed and published by BAE Systems. SOCET SET is notable because it was the first commercial digital photogrammetry software program. Prior to SOCET SET, all photogrammetry programs were primarily analog or custom systems built for government agencies.
SOCET SET inputs digital aerial photographs, taken in stereo (binocular) fashion, and from those photos it automatically generates a digital elevation model, digital feature (vector data), and orthorectified images (called Orthophotos). The output data is used by customers to create digital maps, and for mission planning and targeting purposes.
The source images can come from film-based cameras, or digital cameras. The cameras can be mounted in an airplane, or on a satellite. A key requirement of the imagery is that there must be 2 or more overlapping images, taken from different vantage points. This "binocular" characteristic is what makes it mathematically possible to extract the 3-dimensional terrain and feature data from the imagery. See Imaging Spectroscopy for more details on stereo image viewing.
A key step, involving very complex least squares mathematics, is Triangulation which determines exactly where the cameras were positioned when the photographs were taken. Photogrammetrists that contributed to SOCET SET's Triangulation include Scott Miller, Bingcai Zhang, John Dolloff, and Fidel Paderas. If the quality of the triangulation is poor, all subsequent data will have correspondingly poor positional accuracy.
Get your Tutorial Here
SOCET SET inputs digital aerial photographs, taken in stereo (binocular) fashion, and from those photos it automatically generates a digital elevation model, digital feature (vector data), and orthorectified images (called Orthophotos). The output data is used by customers to create digital maps, and for mission planning and targeting purposes.
The source images can come from film-based cameras, or digital cameras. The cameras can be mounted in an airplane, or on a satellite. A key requirement of the imagery is that there must be 2 or more overlapping images, taken from different vantage points. This "binocular" characteristic is what makes it mathematically possible to extract the 3-dimensional terrain and feature data from the imagery. See Imaging Spectroscopy for more details on stereo image viewing.
A key step, involving very complex least squares mathematics, is Triangulation which determines exactly where the cameras were positioned when the photographs were taken. Photogrammetrists that contributed to SOCET SET's Triangulation include Scott Miller, Bingcai Zhang, John Dolloff, and Fidel Paderas. If the quality of the triangulation is poor, all subsequent data will have correspondingly poor positional accuracy.
Get your Tutorial Here
Introduction to Microwave Remote Sensing
Typical radar (RAdio Detection And Ranging) measures the strength and round-trip time of the microwave signals that are emitted by a radar antenna and reflected off a distantsurface or object. The radar antenna alternately transmits and receives pulses at particular microwave wavelengths (in the range 1 cm to 1 m, which corresponds to a frequency range of about 300 MHz to 30 GHz)
and polarizations (waves polarized in a single vertical or horizontal plane).
For an imaging radar system, about 1500 high- power pulses per second are transmitted toward the target or imaging area, with each pulse having a pulse duration (pulse width) of typically 10-50 microseconds (us). The pulse normally covers a smallband of frequencies, centered on the frequency selected for the radar.
Commonly used frequencies and their corresponding wavelengths are specified by a band nomenclature, as follows:
and polarizations (waves polarized in a single vertical or horizontal plane).
For an imaging radar system, about 1500 high- power pulses per second are transmitted toward the target or imaging area, with each pulse having a pulse duration (pulse width) of typically 10-50 microseconds (us). The pulse normally covers a smallband of frequencies, centered on the frequency selected for the radar.
Commonly used frequencies and their corresponding wavelengths are specified by a band nomenclature, as follows:
-
Ka Band: Frequncy 40,000-26,000 MHz; Wavelength (0.8-1.1 cm)
K Band: 26,500-18,500 MHz; (1.1-1.7 cm)
X Band: 12,500-8,000 MHz; (2.4-3.8 cm)
C Band: 8,000-4,000 MHz; (3.8-7.5 cm)
L Band: 2,000-1,000 MHz; (15.0-30.0 cm)
P Band: 1,000- 300 MHz; (30.0-100.0 cm)
INSAT-4CR
India's Geosynchronous Satellite Launch Vehicle, GSLV-F04, had a successful launch today (September 2, 2007) at 18.20 hours from Satish Dhawan Space Centre SHAR (SDSC SHAR), Sriharikota and it placed India’s INSAT-4CR into the Geosynchronous Transfer Orbit (GTO). The 2,140 kg INSAT-4CR was placed in orbit about seventeen minutes after lift off, about 5,000 km away from Sriharikota.
This was the fifth flight of GSLV and the fourth successful one. NSAT-4CR is now orbiting the Earth in GTO with a perigee (nearest point to Earth) of 168 km and an apogee (farthest point to Earth) of 34,710 km with an orbital inclination of 20.7 deg with respect to the equator.
INSAT-4CR is the third satellite in INSAT-4 series. It carries 12 high-power Ku-band transponders designed to provide Direct-To-home (DTH) television services, Video Picture Transmission (VPT) and Digital Satellite News Gathering (DSNG). It was built to replace an identical satellite, INSAT-4C that was lost due to the failure of GSLV-F02 in July 2006.
INSAT-4CR was developed by ISRO Satellite Centre, Bangalore. The payloads were developed by Space Applications Centre, Ahmedabad. Master Control Facility at Hassan is responsible for all post launch operations of the satellite. The successful launch of GSLV-F04 today has demonstrated the operational reliability of GSLV as well as reiterated the end-to-end capability of ISRO to not only build state-of-the-art communication satellites, but also to launch them using the indigenously designed and built launch vehicle.
This was the fifth flight of GSLV and the fourth successful one. NSAT-4CR is now orbiting the Earth in GTO with a perigee (nearest point to Earth) of 168 km and an apogee (farthest point to Earth) of 34,710 km with an orbital inclination of 20.7 deg with respect to the equator.
INSAT-4CR is the third satellite in INSAT-4 series. It carries 12 high-power Ku-band transponders designed to provide Direct-To-home (DTH) television services, Video Picture Transmission (VPT) and Digital Satellite News Gathering (DSNG). It was built to replace an identical satellite, INSAT-4C that was lost due to the failure of GSLV-F02 in July 2006.
INSAT-4CR was developed by ISRO Satellite Centre, Bangalore. The payloads were developed by Space Applications Centre, Ahmedabad. Master Control Facility at Hassan is responsible for all post launch operations of the satellite. The successful launch of GSLV-F04 today has demonstrated the operational reliability of GSLV as well as reiterated the end-to-end capability of ISRO to not only build state-of-the-art communication satellites, but also to launch them using the indigenously designed and built launch vehicle.
Subscribe to:
Posts (Atom)
