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Countdown for India’s lunar mission
Strange rocks made by early lifeforms Prof Yash
Pal THIS UNIVERSE |
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Countdown
for India’s lunar mission The two US instruments that will be included in Chandrayaan-1 are: Mini Synthetic Aperture Radar (MSAR) and Moon Mineralogy Mapper. The MSAR built by the applied Physics Laboratory of Hopkins University and funded by NASA is designed for mapping the shadowed, cold regions of moon for ice deposits. On the other hand, the Mineralogy Mapper jointly built by Brown University and Jet Propulsion Laboratory (JPL) will identify surface mineral composition of the moon and map the chemical composition of its surface. It is my hope and belief that we extend the reach of the human civilisation throughout the solar system. The US and India will be partners on many more technically challenging and scientifically rewarding projects”, observed Michael Griffin, the NASA Administrator. Griffin also said that the data from these two instruments would contribute to increased understanding of the lunar environment. Interestingly, ISRO had received a total of 16 proposals for payloads from various parts of the world in response to its announcement of opportunity. Of these ISRO selected six instruments of which two were from the United States. The remaining include three developed by ESA (European Space Agency) and one from Bulgarian space agency. The ESA payloads to be included in Chandrayaan-1 are (a) low energy x-ray spectrometer from Rutherford Appleton Laboratory of United Kingdom to measure elemental abundance distribute over the lunar surface using the x-ray fluorescence technique, b) near infrared spectrometer from Max Planck Institute of Aeronomie, Germany to detect ad measure lunar mineral abundance, c) Sub Kev atom reflecting analyser from the Swedish Institute of Space Physics developed in collaboration with India to measure volatiles generated due to solar wind impacting on lunar surface and determine the surface magnetic field anomalies. Chandrayaan-1 will also feature a radiation dose monitor experiment from the Bulgarian Space Laboratory. The Indian payloads forming part of the Chandrayaan-1 mission are a) terrain mapping stereo camera having 5m spatial resolution ad 20 km swath, b) a hyper spectral wedge filler camera operating in 400-900 nm band with a spectral resolution of 15nm and spatial resolution of 80m and a swath of 20 km, c) a collimated low energy x-ray spectrometer using CCD (charged couple device) for measuring fluorescent x-rays emanating from the lunar surface, having a footprint approximately 20km; d) a high energy x-ray mapping instrument, employing solid state detectors having a footprint of approximately 40-km, e) solar x-ray monitor, f) a laser ranging instrument with a height resolution of about 10-m. Chandrayaan-1 will also carry a moon impact probe which is conceived as a technology forerunner for future landing missions. The preliminary design review of the Chandrayaan-1 spacecraft has been completed and fabrication of payloads is proceeding space. Similarly, work is in progress to qualify PSOM-XI, carrying 12.4 tonne solid propellant to be used as strap on motors in PSLV to launch. Chandrayaan-1 spacecraft. weighing 525-kg, the spacecraft have a mission life of two years and will carry out the physical and chemical mapping of the moon from 100-km lunar/polar orbit. According to Mr V.N. Goswami, Director of the Ahmedabad-based Physical Research Laboratory, a grants-in-aid institution under India’s Department of Space, which is playing a key role in designing and developing the scientific payloads going into Chandrayaan-1, “the mission’s main objective was to investigate the mineral and chemical distribution on the lunar surface. Our mission will be for the first time explore the topography of the moon.” |
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Strange rocks made by early lifeforms Scientists studied rock outcrops more than 6 miles in length in Pilbara Craton, Western Australia, covering a time period in prehistory of about 80 million years, according to Abigail Allwood of the Australian Centre for Astrobiology at Macquarie University in Sydney. “This has shed light on the conditions that nurtured very early life, and we can use that to predict where life might have emerged on other planets,” Ms Allwood said. “Our next big question is about the nature of the micro-organisms that produced these structures. “We believe that many types of organisms may have coexisted at this time, so that we have not just some of the oldest evidence of life, but we also have the oldest evidence of biodiversity”. Arthur Hickman of the Geological Survey in Western Australia said: “Whether or not these strange formations were created by the first known microbes on Earth or purely by geological or chemical processes has been a subject of ongoing controversy.” The study is strong evidence that the formations are indeed fossilised lifeforms that may have generated the atmospheric oxygen that was subsequently used by other living organisms. “The microbes that created the Pilbara stromatolites probably produced oxygen and thus are likely to have added to the content of the atmosphere as much as 3.5 billion years ago,” Dr Hickman said. By arrangement with The Independent, London |
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THIS UNIVERSE Some times at night when the lights are off and only the TV is on, we switch on the fan. As the speed of the fan changes it seems to be moving backward or forward, depending on its speed. What is the cause of this observation? When your TV is the only light source the fan is illuminated by a source that has a frequency of about 24 per second. This is frame scan rate of a TV set. Your TV set acts as a stroboscope. The fan blades become visible at different position of their orbit during each flash of light from your TV. This position changes as the speed of the fan is changed. If speed could be properly synchronised the fan might even appear to be stationary. Changing the speed one way or the other would give us the impression that they are moving clockwise or anticlockwise. A similar effect is seen for the spokes of car wheels when seen in a movie. Movies are usually made by projecting 24 frames a second. Stroboscopic effects mentioned above become operative. They are especially visible when the car is slowing down to a stop. While sitting out in the courtyard of my house I sometimes hear rumbling sound from the clouds, often for minutes, without any lightning being visible. How can clouds make thunder without any lightning? If the cloud cover is extensive and multi-layered, electric discharges between distant clouds may not be visible. Intervening clouds might shield many of them, while some others might even be almost beyond horizon. Light may not be visible but the sound gets reflected back and forth and could even go beyond horizon. The rumbling might be due to the large number of discharges and echoes of their sound. Does Europa, a moon of Jupiter, contain any life? And what about the hidden side of the moon? The only answer I can give is: There is no positive evidence in either case. Incidentally, the hidden side of the moon is hidden from us only because its orbital period around the earth is the same as its rotation period. Surely that cannot give the hidden part any special advantage for developing life. |
The conclusion of an agreement between the Indian Space Research Organisation (ISRO) and National Aeronautics and Space Administration (NASA) of the United States, for the inclusion of two US-made scientific instruments into India’s unmanned lunar mission Chandrayaan-1 slated for launch in early 2008 by means of an augmented version of the four-stage Polar Satellite Launch Vehicle (PSLV) has led to the finalisation of the payloads to be lofted by Indian moon mission.
Strange rock formations in Australia were produced by the earliest known lifeforms which lived 3,430 million years ago, scientists have said.
The formations are known as stromatolites and the latest study, published in Nature, has found convincing evidence that they were produced by marine microbes — perhaps the first living organisms on earth.