Sunday, June 21, 2020
Indian Space Research Organisation - Free Essay Example
Indian Space Research Organisationââ¬â¢s(ISRO) Chandrayaan ââ¬â Founder of water on Moon Chandrayaan-1 was a scientific investigation ââ¬â by spacecraft ââ¬â of the Moon. The name Chandrayaan means ââ¬Å"Chandra-Moon, Yaan-vehicleâ⬠, ââ¬âin Indian languages (Sanskrit and Hindi) , ââ¬â the lunar spacecraft. Chandrayaan-1 is the first Indian planetary science and exploration mission. It is Indias first unmanned lunar probe. It was launched by the Indian Space Research Organisation in October 2008, and operated until August 2009. The vehicle was successfully inserted into lunar orbit on 8 November 2008. [ On 14 November 2008, the Moon Impact Probe separated from the Chandrayaan orbiter at 20:06 and struck the south pole in a controlled manner, making India the fourth country to place its flag on the Moon. [10] The probe impacted near Shackleton Crater at 20:31 ejecting underground soil that could be analysed for the presence of lunar water ice. The estima ted cost for the project was Rs 386 crore (US$ 80 million). Former President A P J Abdul Kalam, whose idea it was to include the impactor as part of Chandrayaanââ¬â¢s cargo, described the achievement as ââ¬Å"a gift to Pandit Jawaharlal Nehruâ⬠because the event happened on the 119th birth anniversary of Indiaââ¬â¢s first prime minister. As the mini satellite began its nosedive at 8. 06 pm, its altimeter began recording measurements to prepare the ground for a rover to land on the lunar surface during a second mission planned for 2012. Over a two-year period, it was intended to survey the lunar surface to produce a complete map of its chemical characteristics and three-dimensional topography. The polar regions are of special interest as they might contain ice. The lunar mission carries five ISRO payloads and six payloads from other space agencies including NASA, ESA, and the Bulgarian Aerospace Agency, which were carried free of cost. After suffering from several t echnical issues including failure of the star sensors and poor thermal shielding, Chandrayaan stopped sending radio signals at 1:30 AM IST on 29 August 2009 shortly after which, the ISRO officially declared the mission over. Chandrayaan operated for 312 days as opposed to the intended two years but the mission achieved 95 percent of its planned objectives. Among its many achievements was the discovery of the widespread presence of water molecules in lunar soil. The basic components of the chandrayaan-1 spacecraft are: I. The scientific payloads: the instruments that will gather science data. II. The solar array that provides power to the spacecraft. Chandrayaan also carries a battery that stores the power generated by the solar array and feeds it to other systems. III. The thrusters perform fuel burns to change the spacecraftââ¬â¢s trajectory and attitude. IV. The various functional requirements of the spacecraft such as Attitude and Orbit Control, Command processing, House keeping telemetry, Sensor data processing, Thermal management, payload data handling operation, dual gimbaled data transmission antenna pointing , onboard mission management etc would be taken care by the Bus Management Unit (BMU). V. The spacecraft also carries two star sensors and inertial reference unit based on miniaturised gyros providing absolute attitude. The Chandrayaan-1 mission was aimed at high-resolution remote sensing of the Lunar surface in visible, near Infrared, low energy X-rays and high-energy X-ray regions. Specific scientific goals are: i. To prepare a three-dimensional atlas (with a high spatial and altitude resolution of 5-10 m) of both near and far side of the moon. ii. To conduct chemical and mineralogical mapping of the entire lunar surface for distribution of mineral and chemical elements such as Magnesium, Aluminum, Silicon, Calcium, Iron and Titanium as well as high atomic number elements such as Radon, Uranium Thorium with high spatial resolution. i i. By simultaneous photo geological and chemical mapping, we will be able to identify different geological units, which will test the hypothesis for the origin and early evolutionary history of the moon and help in determining the nature of the lunar crust. iii. One of the Areas of Study was Chemical stratigraphy of lunar crust by remote sensing of the central uplands of large lunar craters, and of the South Pole Aitken Region (SPAR), where interior material may be expected (Stratigraphy, a branch of geology, studies rock layers and layering). Chandrayaan-1 was sent to the Moon in a series of orbit-increasing manoeuvres around Earth instead of a direct trajectory to the Moon. At launch the spacecraft was inserted into geostationary transfer orbit (GTO) with an apogee of 22,860 km and a perigee of 255 km. The apogee was increased with a series of five orbit burns conducted over a period of 13 days after launch. The point of closest approach (the point at which two bodies are the c losest) is called the Perigree. The point of farthest excursion is called the Apogee. The Moon Mineralogy Mapper (M3), an imaging spectrometer, was one of the 11 instruments on board Chandrayaan-I that came to a premature end on 29 August. M3 was aimed at providing the first mineral map of the entire lunar surface. Lunar scientists have for decades contended with the possibility of water repositories. They are now increasingly ââ¬Å"confident that the decades-long debate is over,â⬠a report says. ââ¬Å"The moon, in fact, has water in all sorts of places; not just locked up in minerals, but scattered throughout the broken-up surface, and, potentially, in blocks or sheets of ice at depth. The results from the NASAââ¬â¢s Lunar Reconnaissance Orbiter are also ââ¬Å"offering a wide array of watery signals. â⬠Chandrayaan-1 has detected water on the moon. The findings overturn long-held beliefs that the surface of the moon was dry, potentially paving the way for scienti sts to one day set up a permanent research base on the moon. M3 detected absorption features near 2. 8-3. 0 à µm on the surface of the Moon. For silicate bodies, such features are typically attributed to hydroxyl- and/or water-bearing materials. On the Moon, the feature is seen as a widely distributed absorption that appears strongest at cooler high latitudes and at several fresh feldspathic craters. The general lack of correlation of this feature in sunlit M3 data with neutron spectrometer H abundance data suggests that the formation and retention of OH and H2O is an ongoing surficial process. OH/H2O production processes may feed polar cold traps and make the lunar regolith a candidate source of volatiles for human exploration. The data from Chandrayaan-1 has revealed how the moon ââ¬Å"produces its own water. Much like a big sponge, it absorbs charged particles emitted by the sun, which then interact with oxygen on the lunar surface to produce water. A scientific instrument o n Chandrayaan-1 ââ¬â the Sub keV Atom Reflecting Analyser or SARA ââ¬â made this discovery that was published in the latest edition of the Planetary and Space Science journal. A video camera captured the probeââ¬â¢s descent and a spectrometer measured traces of lunar gas and dust. The Chandrayaan orbiter is analysing the dust kicked up by the probe when it crashed on the moonââ¬â¢s surface. Video footage of the probeââ¬â¢s descent and data from the probeââ¬â¢s instruments have been relayed to the spacecraft and ground stations for analysis. The spacecraft, which takes about two hours to go around the moon, was behind the celestial body when the impact occurred. Recogntition and Award for Indian Space Research Organisationââ¬â¢s Chandrayaan Mission The AIAA American Institute of Aeronautics and Astronautics has selected ISROs Chandrayaan-1 mission as one of the recipients of its annual, AIAA SPACE 2009, awards, which recognize key contributions to space scie nce and technology. The International Lunar Exploration Working Group (ILEWG) chose the Chandrayaan-1 team for giving the International Cooperation award, M, Annadurai, project director, Chandrayaan-1. The Chandrayaan team of the Indian Space Research Organisation (ISRO) was chosen for the award for accommodation and tests of the most international lunar payload ever (from 20 countries consisting of India, the European Space Agency representing 17 European countries, NASA and Bulgaria) and the successful launch of the probe on PSLV rocket on 22 October and the lunar insertion of the spacecraft carried out subsequently. ISRO is also planning a second version of Chandrayaan named Chandrayaan II. According to former ISRO Chairman G. Madhavan Nair, The Indian Space Research Organisation (ISRO) hopes to land two motorised rovers- one Russian and another Indian on the Moon in 2013, as a part of its second Chandrayaan mission. The rover will be designed to move on wheels on the luna r surface, pick up samples of soil or rocks, do on-site chemical analysis and send the data to the mother-spacecraft Chandrayaan II, which will be orbiting above. How was the Moon formed? There are various theories on the evolution of Earth and Moon system. Currently four main hypotheses have been considered to explain the origin of the Moon: 1. Simultaneous Formation: Earth and the Moon were formed from the solar nebula near each other. This theory is able to explain why the Earth and the Moon rocks are isotopically so similar, but cannot explain why the Moon is depleted in Iron (Fe). 2. Capture: Moon formed somewhere else in the Solar System where the iron content was lower. After it formed, it drifted close to the Earth and was captured by the Earthââ¬â¢s gravitational field. This theory cannot explain why the Earth and the Moon rocks are isotopically similar but explains the high angular momentum of the Earth-Moon system. 3. Fission: According to this hypothesis, the Mo on broke off from the hot molten Earth while the Earth was spinning very rapidly. This hypothesis can explain why the Earth and the Moon rocks are similar, chemically and isotopically, and the low iron content of the Moon, but is not able to explain the high angular momentum of the Earth-Moon system. 4. Giant-Impact: This hypothesis suggests that a body about 1-3 times the size of Mars impacted on the Earth during the last stages of the Earthââ¬â¢s formation, after the Earthââ¬â¢s iron core has already formed. When the impact occurred, it ejected a large part of the Earth into space and the ejecta then began orbiting the Earth. The material blasted off the Earth coalesced into the Moon. This hypothesis is able to explain (a) the missing Moon iron as most of the material blasted into space would have been depleted in iron, (b) Moon rocks and Earth rocks are isotopically similar and (c) why the Moonââ¬â¢s orbit as well as the Earthââ¬â¢s orbit are tilted. The giant i mpact hypothesis however have some difficulties since numerical models predict that a large fraction of the Moon would come from the impactor, leading to the same dilemma as the Capture theory. Is there water-ice present on the Moon? The comets and meteorites continuously bombard the surface of the Moon. Many of these objects contain water and as a result of their impact may leave water molecules on the lunar surface. Solar wind hydrogen bombarding the lunar surface continuously may also lead to production of water molecule through interaction with oxygen present in the lunar soils. Due to solar heating much of this water evaporate and lost into space very fast. However, the current hypothesis is that some of the water molecules may reach areas that are permanently shadowed from sunlight and gets trapped and significant traces of water/water ice may be present in such regions of the Moon. Due to the very slight tilt (~ 1. 5à °) of the Moons axis, some of the deep craters particu larly near the polar regions never receive any light from the Sun they are permanently shadowed and can act as permanent trap of water molecules and in such craters scientists expect to find water in frozen form, if it is there at all. The Radar reflectivity experiments performed by Clementine hinted at the possibility of existence of large amounts of water frozen on these permanently shadowed regions of the moon. Lunar Prospectors neutron spectrometer detected bursts of slow neutrons over the moons poles, suggesting presence of hydrogen atoms and hence possible presence of water/ice. However, these experiments could not decisively confirm the presence of water/ice on moon, which still remains a mystery. If there is water ice present on the Moon then we would not have to transport water from Earth to the Moon, which would be extremely expensive. But instead will be able to rely on lunar ice. This is important for a cost-effective lunar habitation. What is the temperature on t he moon? The moon undergoes extremes in temperature the side of the Moon receiving sunlight becomes scorching hot at about 130 ? C, and freezing cold at -180 ? C on the night side. Is there any Life on moon? So far none of the lunar missions have detected any signature of presence of life on the Moon.
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