Today's Headlines - 09 August 2023
Nuclear-powered rocket cut travel time to Mars
GS Paper - 3 (Energy)
In less than three years, NASA could be testing a nuclear rocket in space. The space agency and the Defense Advanced Research Projects Agency, or DARPA, announced that Lockheed Martin had been selected to design, build and test a propulsion system that could one day speed astronauts on a trip to Mars. The program is named DRACO, short for the Demonstration Rocket for Agile Cislunar Operations.
What if a spacecraft could get to Mars in half the time it currently takes?
Every 26 months or so, Mars and Earth are close enough for a shorter journey between the worlds. But even then it is a pretty long trip, lasting seven to nine months. For most of the time, the spacecraft is just coasting through space.
But if the spacecraft could continue accelerating through the first half of the journey and then start slowing down again, the travel time could be slashed.
Current rocket engines, which typically rely on the combustion of a fuel like hydrogen or methane with oxygen, are not efficient enough to accomplish that; there is not enough room in the spacecraft to carry that much propellant.
But nuclear reactions, generating energy from the splitting of uranium atoms, are much more efficient.
The DRACO engine would consist of a nuclear reactor that would heat hydrogen from a chilly minus 420 degrees Fahrenheit to a toasty 4,400 degrees, with the hot gas shooting from a nozzle to generate thrust. Greater fuel efficiency could speed up journeys to Mars, reducing the amount of time astronauts spend exposed to the treacherous environment of deep space.
Nuclear propulsion could also have uses closer to home, which is why DARPA is investing in the project. The technology may allow rapid maneuvers of military satellites in orbit around Earth.
Flashback
Nuclear propulsion for space is not a new idea. In the 1950s and 1960s, Project Orion — financed by NASA, the Air Force and the Advanced Research Projects Agency — contemplated using the explosions of atomic bombs to accelerate spacecraft.
At the same time, NASA and other agencies also undertook Project Rover and Project NERVA, efforts that aimed to develop nuclear-thermal engines similar in concept to those now being pursued by the DRACO program.
A series of 23 reactors were built and tested, but none were ever launched to space. Until the end of this program in 1973, NASA had contemplated using nuclear reactors to propel space probes to Jupiter, Saturn and beyond, as well as to provide power at a lunar base.
The technical capabilities, including early safety protocols, remain viable today, Tabitha Dodson, the DRACO project manager, said in a news briefing on 2 August 2023.
A key difference between NERVA and DRACO is that NERVA used weapons-grade uranium for its reactors, while DRACO will use a less-enriched form of uranium. The reactor would not be turned on until it reached space, part of the precautions to minimize the possibility of a radioactive accident on Earth.
#upsc #news #headline #nuclear #rocket #travel #mars #energy #space #propulsion #system #trip #darpa #astronauts #DRACO #demonstration #agile #cislunar #spacecraft #earth #journey #engines #hydrogen #methane #fuel #oxygen #uranium #DARPA #technology #NERVA
Nuclear-powered rocket cut travel time to Mars
GS Paper - 3 (Energy)
In less than three years, NASA could be testing a nuclear rocket in space. The space agency and the Defense Advanced Research Projects Agency, or DARPA, announced that Lockheed Martin had been selected to design, build and test a propulsion system that could one day speed astronauts on a trip to Mars. The program is named DRACO, short for the Demonstration Rocket for Agile Cislunar Operations.
What if a spacecraft could get to Mars in half the time it currently takes?
Every 26 months or so, Mars and Earth are close enough for a shorter journey between the worlds. But even then it is a pretty long trip, lasting seven to nine months. For most of the time, the spacecraft is just coasting through space.
But if the spacecraft could continue accelerating through the first half of the journey and then start slowing down again, the travel time could be slashed.
Current rocket engines, which typically rely on the combustion of a fuel like hydrogen or methane with oxygen, are not efficient enough to accomplish that; there is not enough room in the spacecraft to carry that much propellant.
But nuclear reactions, generating energy from the splitting of uranium atoms, are much more efficient.
The DRACO engine would consist of a nuclear reactor that would heat hydrogen from a chilly minus 420 degrees Fahrenheit to a toasty 4,400 degrees, with the hot gas shooting from a nozzle to generate thrust. Greater fuel efficiency could speed up journeys to Mars, reducing the amount of time astronauts spend exposed to the treacherous environment of deep space.
Nuclear propulsion could also have uses closer to home, which is why DARPA is investing in the project. The technology may allow rapid maneuvers of military satellites in orbit around Earth.
Flashback
Nuclear propulsion for space is not a new idea. In the 1950s and 1960s, Project Orion — financed by NASA, the Air Force and the Advanced Research Projects Agency — contemplated using the explosions of atomic bombs to accelerate spacecraft.
At the same time, NASA and other agencies also undertook Project Rover and Project NERVA, efforts that aimed to develop nuclear-thermal engines similar in concept to those now being pursued by the DRACO program.
A series of 23 reactors were built and tested, but none were ever launched to space. Until the end of this program in 1973, NASA had contemplated using nuclear reactors to propel space probes to Jupiter, Saturn and beyond, as well as to provide power at a lunar base.
The technical capabilities, including early safety protocols, remain viable today, Tabitha Dodson, the DRACO project manager, said in a news briefing on 2 August 2023.
A key difference between NERVA and DRACO is that NERVA used weapons-grade uranium for its reactors, while DRACO will use a less-enriched form of uranium. The reactor would not be turned on until it reached space, part of the precautions to minimize the possibility of a radioactive accident on Earth.
#upsc #news #headline #nuclear #rocket #travel #mars #energy #space #propulsion #system #trip #darpa #astronauts #DRACO #demonstration #agile #cislunar #spacecraft #earth #journey #engines #hydrogen #methane #fuel #oxygen #uranium #DARPA #technology #NERVA
Today's Headlines - 12 August 2023
Russia’s Luna-25 mission
GS Paper - 3 (Space Technology)
As the Chandrayaan-3 mission tightens its orbit around the Moon, Russia was launched its first moon-landing spacecraft in 47 years on 11 August 2023. The Luna-25 mission is scheduled to land on the Moon on 23 August 2023, the same day as Chandrayaan-3’s planned landing.
More about Luna-25
Luna-25 was launched from the Vosthochny cosmodrome in the Russian Far East less than a month after Chandrayaan-3 launched from the Satish Dhawan Space Center in Sriharikota.
The Russian mission will try to land on the lunar South Pole just like the Indian mission, aiming for a prized destination that may hold significant quantities of ice that could be used to extract oxygen and fuel in the future.
If either of the missions succeeds before the other, it will be the first one to land on the lunar South Pole in human history.
Roscosmos, Russia’s ISRO counterparts said that Luna-25 will practice soft-landing, analyse soil samples and conduct long-term scientific research on the Moon’s surface.
The Chandrayaan-3 mission is carrying an orbiter, a lander and a rover. The lander and rover are carrying many scientific payloads.
This is Russia’s first lunar mission since 1976 when the country was part of the Soviet Union and it will be completed without equipment from the European Space Agency (ESA). ESA ended its cooperation with Roscosmos after Russia invaded Ukraine.
Luna-25 has a mass of 1.8 tons and carries 31 kilograms of scientific equipment, including some that it will use to take rock samples from up to a depth of 15 centimetres to test for the presence of water that could be used to support future crewed missions to the Moon.
The mission was originally scheduled to launch in October 2021 but was marred by many delays.
The Russian mission will take a lot less time to reach the Moon than Chandrayaan-3 because the latter is taking a longer route that takes advantage of the gravities of the Earth and the Moon to use a lot less fuel.
Russia willevacuate villagers from a village near the launch site due to a “one in a million chance” that one of the rocket stages that launches could fall to the Earth there.
#upsc #news #headline #russia #luna #mission #space #technology #chandrayaan #moon #spacecraft #vosthochny #cosmodrome #lunar #southpole #indianmission #oxygen #soil #history #land #human #orbiter #ESA #launch #gravaities #earth #october #rover #ISRO #fuel
Russia’s Luna-25 mission
GS Paper - 3 (Space Technology)
As the Chandrayaan-3 mission tightens its orbit around the Moon, Russia was launched its first moon-landing spacecraft in 47 years on 11 August 2023. The Luna-25 mission is scheduled to land on the Moon on 23 August 2023, the same day as Chandrayaan-3’s planned landing.
More about Luna-25
Luna-25 was launched from the Vosthochny cosmodrome in the Russian Far East less than a month after Chandrayaan-3 launched from the Satish Dhawan Space Center in Sriharikota.
The Russian mission will try to land on the lunar South Pole just like the Indian mission, aiming for a prized destination that may hold significant quantities of ice that could be used to extract oxygen and fuel in the future.
If either of the missions succeeds before the other, it will be the first one to land on the lunar South Pole in human history.
Roscosmos, Russia’s ISRO counterparts said that Luna-25 will practice soft-landing, analyse soil samples and conduct long-term scientific research on the Moon’s surface.
The Chandrayaan-3 mission is carrying an orbiter, a lander and a rover. The lander and rover are carrying many scientific payloads.
This is Russia’s first lunar mission since 1976 when the country was part of the Soviet Union and it will be completed without equipment from the European Space Agency (ESA). ESA ended its cooperation with Roscosmos after Russia invaded Ukraine.
Luna-25 has a mass of 1.8 tons and carries 31 kilograms of scientific equipment, including some that it will use to take rock samples from up to a depth of 15 centimetres to test for the presence of water that could be used to support future crewed missions to the Moon.
The mission was originally scheduled to launch in October 2021 but was marred by many delays.
The Russian mission will take a lot less time to reach the Moon than Chandrayaan-3 because the latter is taking a longer route that takes advantage of the gravities of the Earth and the Moon to use a lot less fuel.
Russia willevacuate villagers from a village near the launch site due to a “one in a million chance” that one of the rocket stages that launches could fall to the Earth there.
#upsc #news #headline #russia #luna #mission #space #technology #chandrayaan #moon #spacecraft #vosthochny #cosmodrome #lunar #southpole #indianmission #oxygen #soil #history #land #human #orbiter #ESA #launch #gravaities #earth #october #rover #ISRO #fuel
Today's Headlines - 16 August 2023
Isro’s space probe to study the Sun
GS Paper - 3 (Space Technology)
The Indian Space Research Organisation (Isro) released images of the Aditya-L1 mission — the space agency’s first attempt to study the Sun. The satellite has reached the Satish Dhawan Space Center (SDSC) in Sriharikota, Andhra Pradesh, for its integration with the launch vehicle, PSLV.
What is the Aditya-L1 mission?
The Aditya-L1 will observe the Sun from a close distance, and try to obtain information about its atmosphere and magnetic field.
It’s equipped with seven payloads (instruments) on board to study the Sun’s corona, solar emissions, solar winds and flares, and Coronal Mass Ejections (CMEs), and will carry out round-the-clock imaging of the Sun.
Why is studying the Sun important?
Every planet, including Earth and the exoplanets beyond the Solar System, evolves — and this evolution is governed by its parent star.
The solar weather and environment affect the weather of the entire system. Variations in this weather can change the orbits of satellites or shorten their lives, interfere with or damage onboard electronics, and cause power blackouts and other disturbances on Earth. Knowledge of solar events is key to understanding space weather.
To learn about and track Earth-directed storms, and to predict their impact, continuous solar observations are needed.
Every storm that emerges from the Sun and heads towards Earth passes through L1, and a satellite placed in the halo orbit around L1 of the Sun-Earth system has the major advantage of continuously viewing the Sun without any occultation/eclipses.
L1 refers to Lagrangian/Lagrange Point 1, one of five points in the orbital plane of the Earth-Sun system. Lagrange Points, named after Italian-French mathematician Josephy-Louis Lagrange, are positions in space where the gravitational forces of a two-body system (like the Sun and the Earth) produce enhanced regions of attraction and repulsion.
These can be used by spacecraft to reduce fuel consumption needed to remain in position. The L1 point is home to the Solar and Heliospheric Observatory Satellite (SOHO), an international collaboration project of NASA and the European Space Agency (ESA).
The L1 point is about 1.5 million km from Earth, or about one-hundredth of the way to the Sun. Aditya L1 will perform continuous observations looking directly at the Sun.
NASA’s Parker Solar Probe, launched in 2018, has already gone far closer — but it will be looking away from the Sun.
The earlier Helios 2 solar probe, a joint venture between NASA and the space agency of erstwhile West Germany, went within 43 million km of the Sun’s surface in 1976.
#upsc #news #headline #ISRO #study #sun #space #technology #india #space #research #technology #aditya #mission #SDSC #satishdhawanspacecenter #srihorikota #andhrapradesh #PSLV #distance #magnetic #corona #solar #planet #weather #earth #repulsion #gravitational #forces #fuel #SOHO #NASA #germany #surface
Isro’s space probe to study the Sun
GS Paper - 3 (Space Technology)
The Indian Space Research Organisation (Isro) released images of the Aditya-L1 mission — the space agency’s first attempt to study the Sun. The satellite has reached the Satish Dhawan Space Center (SDSC) in Sriharikota, Andhra Pradesh, for its integration with the launch vehicle, PSLV.
What is the Aditya-L1 mission?
The Aditya-L1 will observe the Sun from a close distance, and try to obtain information about its atmosphere and magnetic field.
It’s equipped with seven payloads (instruments) on board to study the Sun’s corona, solar emissions, solar winds and flares, and Coronal Mass Ejections (CMEs), and will carry out round-the-clock imaging of the Sun.
Why is studying the Sun important?
Every planet, including Earth and the exoplanets beyond the Solar System, evolves — and this evolution is governed by its parent star.
The solar weather and environment affect the weather of the entire system. Variations in this weather can change the orbits of satellites or shorten their lives, interfere with or damage onboard electronics, and cause power blackouts and other disturbances on Earth. Knowledge of solar events is key to understanding space weather.
To learn about and track Earth-directed storms, and to predict their impact, continuous solar observations are needed.
Every storm that emerges from the Sun and heads towards Earth passes through L1, and a satellite placed in the halo orbit around L1 of the Sun-Earth system has the major advantage of continuously viewing the Sun without any occultation/eclipses.
L1 refers to Lagrangian/Lagrange Point 1, one of five points in the orbital plane of the Earth-Sun system. Lagrange Points, named after Italian-French mathematician Josephy-Louis Lagrange, are positions in space where the gravitational forces of a two-body system (like the Sun and the Earth) produce enhanced regions of attraction and repulsion.
These can be used by spacecraft to reduce fuel consumption needed to remain in position. The L1 point is home to the Solar and Heliospheric Observatory Satellite (SOHO), an international collaboration project of NASA and the European Space Agency (ESA).
The L1 point is about 1.5 million km from Earth, or about one-hundredth of the way to the Sun. Aditya L1 will perform continuous observations looking directly at the Sun.
NASA’s Parker Solar Probe, launched in 2018, has already gone far closer — but it will be looking away from the Sun.
The earlier Helios 2 solar probe, a joint venture between NASA and the space agency of erstwhile West Germany, went within 43 million km of the Sun’s surface in 1976.
#upsc #news #headline #ISRO #study #sun #space #technology #india #space #research #technology #aditya #mission #SDSC #satishdhawanspacecenter #srihorikota #andhrapradesh #PSLV #distance #magnetic #corona #solar #planet #weather #earth #repulsion #gravitational #forces #fuel #SOHO #NASA #germany #surface
Today's Headlines - 24 August 2023
Poor nations forced to rely on fossil fuels
GS Paper - 3 (Energy)
Poor countries with heavy debts have been forced to continue to rely on fossil fuels for generating revenue to return the loans taken from richer countries and private lenders to meet various economic exigencies like the pandemic three years ago, a new report said. These countries, mostly in the global south, may find it impossible to phase out fossil fuels and transition to renewable energy as revenues from fossil fuel projects “are often overinflated and require huge investments to reach expected returns, leading to further debt”.
What is the “debt-fossil fuel trap”?
The report, ‘The Debt-Fossil Fuel Trap’, published on 21 August 2023 by the anti-debt campaigners Debt Justice and partners in affected countries.
The global south — a term used for developing, less developing and underdeveloped countries, located in Africa, Latin America, and Asia — countries are increasingly being burdened by enormous debts in recent years.
Their “external debt payments (money borrowed from richer countries, or multilateral creditors like the World Bank and IMF, or private lenders such as banks) has gone up by 150% between 2011 and 2023, reaching their highest levels in 25 years”, said the report.
Moreover, 54 countries are in a debt crisis — they had to cut their public sending budgets during the pandemic to repay the loans, the analysis found.
The situation is worsened by extreme weather events, which force these countries to borrow more money as they lack adequate finances and resources for adaptation, mitigation and tackling loss and damage.
For instance, Dominica’s debt as a percentage of GDP rose from 68% to 78% after Hurricane Maria hit the island in 2017.
To deal with the mounting debts, these countries have turned to extracting more fossil fuels.
The country’s strategy to reduce debt may end up adding to debt levels without generating adequate revenue to repay, which could force Argentia to further expand its fossil fuel projects, the report added. This is known as the “debt-fossil fuel trap”.
Ending the high debt burdens
The report has laid out a few recommendations to help global south countries exit the “debt-fossil fuel trap”.
It said clean energy, wealthy governments and institutions must implement “ambitious debt cancellation for all countries that need it, across all creditors, free from economic conditions.
They should also stop accepting repayments made through fossil fuel projects’ revenue.
Meanwhile, “Bilateral and multilateral finance should be aligned with a 1.5 degree warming scenario and fair shares calculations, and not be used to finance fossil fuels.
#upsc #news #headline #nations #fossilfuels #energy #countries #revenue #pandemic #globalsouth #fuel #trap #africa #latin #worldbank #IMF #payments #GDP #island #dominica #strategy #projects #warming #bilateral #multilateral #finance #fairshares #america #asia #justice #renewable #poornations #forced
Poor nations forced to rely on fossil fuels
GS Paper - 3 (Energy)
Poor countries with heavy debts have been forced to continue to rely on fossil fuels for generating revenue to return the loans taken from richer countries and private lenders to meet various economic exigencies like the pandemic three years ago, a new report said. These countries, mostly in the global south, may find it impossible to phase out fossil fuels and transition to renewable energy as revenues from fossil fuel projects “are often overinflated and require huge investments to reach expected returns, leading to further debt”.
What is the “debt-fossil fuel trap”?
The report, ‘The Debt-Fossil Fuel Trap’, published on 21 August 2023 by the anti-debt campaigners Debt Justice and partners in affected countries.
The global south — a term used for developing, less developing and underdeveloped countries, located in Africa, Latin America, and Asia — countries are increasingly being burdened by enormous debts in recent years.
Their “external debt payments (money borrowed from richer countries, or multilateral creditors like the World Bank and IMF, or private lenders such as banks) has gone up by 150% between 2011 and 2023, reaching their highest levels in 25 years”, said the report.
Moreover, 54 countries are in a debt crisis — they had to cut their public sending budgets during the pandemic to repay the loans, the analysis found.
The situation is worsened by extreme weather events, which force these countries to borrow more money as they lack adequate finances and resources for adaptation, mitigation and tackling loss and damage.
For instance, Dominica’s debt as a percentage of GDP rose from 68% to 78% after Hurricane Maria hit the island in 2017.
To deal with the mounting debts, these countries have turned to extracting more fossil fuels.
The country’s strategy to reduce debt may end up adding to debt levels without generating adequate revenue to repay, which could force Argentia to further expand its fossil fuel projects, the report added. This is known as the “debt-fossil fuel trap”.
Ending the high debt burdens
The report has laid out a few recommendations to help global south countries exit the “debt-fossil fuel trap”.
It said clean energy, wealthy governments and institutions must implement “ambitious debt cancellation for all countries that need it, across all creditors, free from economic conditions.
They should also stop accepting repayments made through fossil fuel projects’ revenue.
Meanwhile, “Bilateral and multilateral finance should be aligned with a 1.5 degree warming scenario and fair shares calculations, and not be used to finance fossil fuels.
#upsc #news #headline #nations #fossilfuels #energy #countries #revenue #pandemic #globalsouth #fuel #trap #africa #latin #worldbank #IMF #payments #GDP #island #dominica #strategy #projects #warming #bilateral #multilateral #finance #fairshares #america #asia #justice #renewable #poornations #forced
Today's Headlines - 03 September 2023
Largest indigenously developed N-plant starts ops
GS Paper - 3 (Energy)
The third unit of the indigenously developed 700-megawatt electric (MWe) nuclear power reactor at the Kakrapar Atomic Power Project (KAPP3) in Gujarat has commenced operations at full capacity. This comes a little over three years since the unit achieved its ‘first criticality’ – a technical term that signifies the initiation of a controlled, but sustained nuclear fission reaction – in July 2020. On 30 June this year, the unit had started commercial operations.
More about the News
In India’s civilian nuclear programme, this is seen as a landmark event, given that KAPP-3 is the country’s first 700 MWe unit and the biggest indigenously developed variant of the Pressurised Heavy Water Reactor (PHWR).
The PHWRs, which use natural uranium as fuel and heavy water as moderator, constitute the mainstay of India’s nuclear power fleet.
Till now, the biggest reactor of indigenous design was the 540 MWe PHWR, two of which have been deployed in Tarapur, Maharashtra.
For India, the operationalisation of its first 700MWe reactor is a significant scale up in technology, both in terms of the optimisation of its PHWR design — the new 700MWe unit addresses the excess thermal margins and also marks an improvement in the economies-of-scale, without significant design changes to the 540 MWe reactor.
Flashback
As India works to ramp up its existing nuclear power capacity of 7,480 MWe to 22,480 MWe by 2031, the 700MWe capacity would constitute the biggest component of this expansion plan. Currently, nuclear power capacity constitutes around 2 per cent of the total installed capacity of 4,17,668 MW (May 31).
Significantly, as India’s civilian nuclear sector gears up to its next frontier — building a 900 MWe Pressurised Water Reactors (PWRs) of indigenous design – the experience of executing the larger 700MWe reactor design would come in handy, especially with respect to the improved capability of making large-size pressure vessels, alongside India’s own isotope enrichment plants being developed to supply a part of the required enriched uranium fuel to power these new generation reactors over the next decade or so, according to DAE officials.
The first ‘pour of concrete’ for laying the foundation of KAPP-3 happened in November 2010 and this unit was originally expected to be commissioned in 2015.
#upsc #news #headline #largest #indigenously #devloped #Nplant #energy #megawatt #kakrapar #atomic #powerproject #gujarat #firstcriticality #india #civilian #nuclear #programme #heavywater #PHWR #tarapur #capacity #pour #concrete #DAE #uranium #fuel #maharashtra #moderator #fission #first #initiation #thirdunit #electric #landmark #pressurised #thermal #margins #economies #november
Largest indigenously developed N-plant starts ops
GS Paper - 3 (Energy)
The third unit of the indigenously developed 700-megawatt electric (MWe) nuclear power reactor at the Kakrapar Atomic Power Project (KAPP3) in Gujarat has commenced operations at full capacity. This comes a little over three years since the unit achieved its ‘first criticality’ – a technical term that signifies the initiation of a controlled, but sustained nuclear fission reaction – in July 2020. On 30 June this year, the unit had started commercial operations.
More about the News
In India’s civilian nuclear programme, this is seen as a landmark event, given that KAPP-3 is the country’s first 700 MWe unit and the biggest indigenously developed variant of the Pressurised Heavy Water Reactor (PHWR).
The PHWRs, which use natural uranium as fuel and heavy water as moderator, constitute the mainstay of India’s nuclear power fleet.
Till now, the biggest reactor of indigenous design was the 540 MWe PHWR, two of which have been deployed in Tarapur, Maharashtra.
For India, the operationalisation of its first 700MWe reactor is a significant scale up in technology, both in terms of the optimisation of its PHWR design — the new 700MWe unit addresses the excess thermal margins and also marks an improvement in the economies-of-scale, without significant design changes to the 540 MWe reactor.
Flashback
As India works to ramp up its existing nuclear power capacity of 7,480 MWe to 22,480 MWe by 2031, the 700MWe capacity would constitute the biggest component of this expansion plan. Currently, nuclear power capacity constitutes around 2 per cent of the total installed capacity of 4,17,668 MW (May 31).
Significantly, as India’s civilian nuclear sector gears up to its next frontier — building a 900 MWe Pressurised Water Reactors (PWRs) of indigenous design – the experience of executing the larger 700MWe reactor design would come in handy, especially with respect to the improved capability of making large-size pressure vessels, alongside India’s own isotope enrichment plants being developed to supply a part of the required enriched uranium fuel to power these new generation reactors over the next decade or so, according to DAE officials.
The first ‘pour of concrete’ for laying the foundation of KAPP-3 happened in November 2010 and this unit was originally expected to be commissioned in 2015.
#upsc #news #headline #largest #indigenously #devloped #Nplant #energy #megawatt #kakrapar #atomic #powerproject #gujarat #firstcriticality #india #civilian #nuclear #programme #heavywater #PHWR #tarapur #capacity #pour #concrete #DAE #uranium #fuel #maharashtra #moderator #fission #first #initiation #thirdunit #electric #landmark #pressurised #thermal #margins #economies #november