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Science and Technology Current Affairs for Prelims 2019
About Me . Bachelors and Masters in Physics from Indian Institute of Science (ISc), Bangalore .INSPIRE Scholar, DST Govt. of India Interested in Physics, current affairs, economics.... . Physicist, Blogger, Teacher.... Wrote UPSC CSE Mains 2017 Research Publication in Journal of Applied Physics
ISRO Going Green . ISRO is developing a environment-friendly propellant to power satellites and spacecraft. . The new propellant is a blend based on hydroxylammonium nitrate (HAN). It is a monopropellant, i.e. chemical propulsion fuel does not require a separate oxidizer. . The formulation consists of HAN, ammonium nitrate, methanol and water. . Methanol ensures combustion stability, AN has capacity to control the burn rate and lower the freezing point of the propellant.
Hydrazine . Most used mono propellent . High specific impulse High thrust can be obtained per unit fuel burnt Drawbacks - Toxic, Carcinogenic, corrosive , difficulty in handling and storage Currently Hydrazine rocket fuel is being used. Due to its high performance characteristics, hydrazine has dominated the space industry as the choice of propellant for decades, despite the drawbacks and negative impact on environment HAN a suitable alternative for Hydrazine
Rustom2 Rustom 2 drone is a medium-altitude, long-endurance unmanned aerial vehicle, developed on the lines of predator drones of the United States. Objective To carry out surveillance for the armed forces with an endurance of 24 hours The drone was developed for use by Indian Army, Navy and Air force, mainly for intelligence, surveillance and reconnaissance (ISR) operations. The medium-altitude prototype can fly at over 22,000 ft and is a long-endurance UAV that has an approximate flight time of 20 hours. It can fly at around 280 km/h and carry a variety of payloads I Rustom 2 can fly missions on manual as well as autonomous modes
The Shephard System . Blue Origin, an US aerospace company has launched the New Shepard rocket and space capsule. The New Shepard system is a fully reusable vertical takeoff, vertical landing (VTVL) space vehicle. Named after the first American astronaut in space, Alan Shepard .New Shepard 2.0 space capsule is designed to fly commercial payloads and passengers on space flights for science and tourism.
Gravity Recovery and Climate Experiment Follow-On mission . NASA will soon launch a pair of new spacecraft that will observe our planet's dynamic water cycle, ice sheets and crust . GRACE-FO mission is a partnership between NASA and the German Research Centre for Geosciences (GFZ) . GRACE-FO is a successor to the original GRACE mission GRACE missions measure variations in gravity over Earth's surface, It produced a gravity map of the earth every month GRACE-FO will track Earth's water movement to monitor changes in underground water storage, the amount of water in large lakes and rivers, soil moisture, ice sheets and glaciers, and sea level caused by the addition of water to the ocean. . These observations will provide a unique view of Earth's climate
GRACE In News . GRACE mission confirmed that a massive redistribution of freshwater is occurring across the Earth, with middle-latitude belts drying and the tropics and higher latitudes gaining water supplies . Causes - Combination of the effects of climate change, vast human withdrawals of groundwater and simple natural changes are behind this. . The resulting map of the findings shows an overall pattern, in which ice sheets and glaciers lose by far the most mass at the poles, but at the same time, middle latitudes show multiple areas of growing dryness even as higher latitudes and the tropical belt tend to see increases in water.
InSight Mission . InSight is part of NASA's Discovery Program It is the first mission to look deep beneath the Martian surface, and stdudy the planet's interior by measuring its heat output and listening for marsquakes It will use the seismic waves generated by marsquakes and developa map of the planet's deep interior. . The mission seeks to unravel "How the terrestrial planets formed"
Bangabandhu Satellite Bangabandhu is Bangladesh's first communications satellite. It is designed to provide a wide range of broadcast and communication services throughout the country It is named after Bangladesh's "Father of the Nation"- Bangabandhu Sheikh Mujibur Rahman. . Once operational, citizens of Bangladesh will gain access to the Internet, phone services, radio, backhaul, direct-to-home TV, and other related services. So far, a majority of Bangladesh's communications was based on rented transponders from neighbouring countries and this satellite will make the country autonomous, in terms of telecommunications and broadcasting services .
Pinaka Rocket . The indigenous Pinaka rocket system of the Defence Research and Development Organisation (DRDO) is being evolved into a precision-guided missile, with enhanced range and accuracy to hit its targets It is used to neutralize the enemy's positions that are strategically important for the enemy. The advanced versions of this system can also be used to conduct surgical srikes even without entering into the enemy area. The launcher can fire 12 rockets with 1.2 tonnes of high explosives within 44 seconds and destroy a target area of 4-square km at a time. Pinaka is capable of working in different modes - autonomous mode, stand-alone mode, remote mode and manual mode. .
Dhanush Artillery Gun . The indigenously upgraded artillery gun Dhanush has successfully completed final trials and is ready for induction into the Army. Dhanush is an upgraded version of the Swedish Bofors gun procured by India in the mid-1980s. . Dhanush is a 155-mm, 45-calibre gun with a maximum range of 40 km in salvo mode.
Chandrayan-1 . Chandrayan-1 was launched by India in October, 2009 using the PSLV- C11 . Objective : Prepare a three dimensional atlas (with high spatial and altitude resolution) of the moon It aimed to conduct chemical and mineralogical mapping of the entire lunar surface for distribution of mineral and chemical elements . It performed a high resolution remote sensing of the moon in visible, near infra red, low enery X-rays, nad high energy X-ray regions
Agni Missiles . These are long-range ballistic missiles that can carry nuclear warheads. They are classified into three types: Medium Range Ballistic Missiles (MRBM), Intermediate Range Ballistic Missiles (IRBM) and Intercontinental Ballistic Missiles (ICBM). . Agni MRBM with range 700-1200 Km . Agni I, Agni III and Agni IV are IRBM; Agni IV has a range of 2500-3700 Km . Agni V and Agni VI - ICBM; Agni V is tested and has a range of 5000-8000Km
Outer Space Treaty . The Outer Space Treaty represents the basic legal framework of international space law. . Among its principles, it bars states party to the treaty from placing weapons of mass destruction in orbit of Earth, installing them on the Moon or any other celestial body, or otherwise stationing them in outer space. It exclusively limits the use of the Moon and other celestial bodies to peaceful purposes and expressly prohibits their use for testing weapons of any kind, conducting military maneuvers, or establishing mlitary bases, installations, and fortifications
Outer Space Treaty .The treaty also states that the exploration of outer space shall be done to benefit all countries and that space shall be free for exploration and use by all the States. . The treaty explicitly forbids any government from claiming a celestial resource such as the Moon or a plane . However, the State that launches a space object retains jurisdiction and control over that object.. The State is also liable for damages caused by their space object
Kessler Syndrome The Kessler syndrome (also called the Kessler effect or collisional cascading), proposed by the NASA scientist Donald J. Kessler . It is a scenario in which the density of objects in low earth orbit (LEO) is high enough that collisions between objects could cause a cascade where each collision generates space debris that increases the likelihood of further collisions. One implication is that the distribution of debris in orbit could render space activities and the use of satellites in specific orbital ranges infeasible for many generations
United Nations Office for Outer Space Affairs . The United Nations Office for Outer Space Affairs (UNOOSA) works to promote international cooperation in the peaceful use and exploration of space, and in the utilisation of space science and technology for sustainable economic and social development. The Office assists any United Nations Member States to establish legal and regulatory frameworks to govern space activities and strengthens the capacity of developing countries to use space science technology and applications for development by helping to integrate space capabilities into national development programmes .UNOOSA is also responsible for implementing the Secretary-General's responsibilities under international space law and maintaining the United Nations Register of Objects Launched into Outer Space. UNOOSA is the current secretariat of the International Committee on Global Navigation Satellite Systems
Pad Abort Test by ISRO PAT (pad abort test) is the first in a series of tests to qualify a crew escape system technology of a manned mission in the future It is an emergency escape measure to quickly pull the astronaut cabin along with crew out to a safe distance from launch vehicle during a launch abort
Cruise Missiles . Cruise missiles can also be launched from air and fly within Earth's atmosphere . They have their own engines and wings to strike the target . They can be supersonic or sub-sonic and are highly accurate . They usually carry conventional warheads although some cruise missiles can also be equipped with nuclear warheads These missiles are guided. That is, the flight path is pre-determined and very small alterations in flight are possible, if at all. and t are possble, f at al . Examples include Brahmos Missiles, Nirbhay Missile
Nirbhay First long range subsonic cruise missile . Nirbhay is an all-weather long-range nuclear warhead capable cruise missile with stealth and high accuracy. . The missile has a range of more than 1000 km. It carries a ring laser gyroscope for high-accuracy navigation and a radio altimeter for the height determination. . It is capable of being launched from multiple platforms on land, sea and air and will be inducted into Indian Navy, Army, and Air Force
Hubble Space Telescope The Hubble Space Telescope is a large telescope in space. Hubble Space telescope was launched in 1990. . It was built by the United States space agency NASA, with contributions from the European Space Agency. . Hubble is the only telescope designed to be serviced in space by astronauts. Expanding the frontiers of the visible Universe, the Hubble Space Telescope looks deep into space with cameras that can see across the a varied range of optical spectrum from infrared to ultraviolet
Parker Solar Probe Parker Solar Probe will travel through the sun's atmosphere, closer to the surface than any spacecraft before it, facing brutal heat and radiation conditions and ultimately providing humanity with the closest-ever observations of a star . It wil trace the flow of energy that heats and accelerates the solar corona and solar wind. . It will determine the structure and dynamics of the plasma and magnetic fields at the sources of the solar wind. . It will explore mechanisms that accelerate and transport energetic particles
Kepler Space telescope . Launched in 2009, the Kepler mission is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine the fraction of the hundreds of billions of stars in our galaxy that might have such planets. . Since the launch of the observatory in 2009, astronomers have discovered thousands of extra-solar planets, or exoplanets, through this telescope alone. Most of them are planets that are ranging between the size of Earth and Neptune
GAOFEN-11 It is an optical remote sensing satellite, launched by China as part of its high- resolution Earth observation project. It will aid in the Belt and Road Initiative. It was the 282nd flight mission by a Long March carrier rocket The satellite can be used for land survey, urban planning, road network design, agriculture, and disaster relief. Gaofen-11l become part of the China High-resolution Earth Observation System (CHEOS), initiated in 2010 to provide all-weather, all-day coverage by 2020
Summary of the Mandal Commission Report Siva Prasad