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 - 07 September 2023
IPBES report on Biodiversity loss
GS Paper - 3 (Environment)
In the most extensive study on invasive species carried out till date, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) in its new publication – the “Assessment Report on Invasive Alien Species and their Control’’ – has found that there are 37,000 alien species, including plants and animals, that have been introduced by many human activities to regions and biomes around the world, including more than 3,500 invasive alien species and that invasive alien species have played a key role in 60% of global plant and animal extinctions recorded.
Highlight of the report
The report, which was released on 4 September 2023, said that invasive alien species are one of the five major direct drivers of biodiversity loss globally, alongside land and sea use change, direct exploitation of organisms, climate change, and pollution.
The report has noted that the number of alien species (species introduced to new regions through human activities) has been rising continuously for centuries in all regions, but are now increasing at unprecedented rates, with increased human travel, trade and the expansion of the global economy.
Not all alien species establish and spread with negative impacts on biodiversity, local ecosystems and species, but a significant proportion do – then becoming known as invasive alien species.
About 6% of alien plants; 22% of alien invertebrates; 14% of alien vertebrates; and 11% of alien microbes are known to be invasive, posing major risks to nature and to people, the IPBES has said.
The report further noted that many invasive alien species have been intentionally introduced for their perceived benefits, “without consideration or knowledge of their negative impacts’’ – in forestry, agriculture, horticulture, aquaculture, or as pets.
Nearly 80% of the documented impacts of invasive species on nature’s contribution to people are negative.
The water hyacinth is the world’s most widespread invasive alien species on land. Lantana, a flowering shrub, and the black rat are the second and third most widespread globally. The brown rat and the house mouse are also widespread invasive alien species.
The report said that the annual costs of invasive alien species have at least quadrupled every decade since 1970, as global trade and human travel increased. In 2019, the global economic cost of invasive alien species exceeded $423 billion annually.
These trends are projected to accelerate as the global economy expands, land and seas are used more intensively, and demographic change takes place, the report said.
Invasive alien specieslike Aedes albopictus and Aedes aegyptii spread diseases such as malaria, Zika and West Nile Fever, while others also have an impact on livelihood such as the water hyacinth in Lake Victoria in East Africa led to the depletion of tilapia, impacting local fisheries.
The IPBES report has further warned thatwarming temperatures and climate change could favour the “expansion of invasive species’’.
Flashback
The IPBES released its report following a week- long plenary from 28th August, with representatives of the 143 member States which have approved the report.
IPBES is an independent intergovernmental body established to strengthen the science-policy interface for biodiversity and ecosystem services, working in a similar way to the IPCC, which is the UN’s climate science body.
The study, which has taken place over a period of four years, has been by 86 leading experts from 49 countries, drawing on more than 13,000 references.
#upsc #news #headline #IPBES #biodiversity #loss #enviroment #alien #species #ecosystem #biomes #animals #climate #pollution #chnage #lantana #housemouse #hyacinth #travel
IPBES report on Biodiversity loss
GS Paper - 3 (Environment)
In the most extensive study on invasive species carried out till date, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) in its new publication – the “Assessment Report on Invasive Alien Species and their Control’’ – has found that there are 37,000 alien species, including plants and animals, that have been introduced by many human activities to regions and biomes around the world, including more than 3,500 invasive alien species and that invasive alien species have played a key role in 60% of global plant and animal extinctions recorded.
Highlight of the report
The report, which was released on 4 September 2023, said that invasive alien species are one of the five major direct drivers of biodiversity loss globally, alongside land and sea use change, direct exploitation of organisms, climate change, and pollution.
The report has noted that the number of alien species (species introduced to new regions through human activities) has been rising continuously for centuries in all regions, but are now increasing at unprecedented rates, with increased human travel, trade and the expansion of the global economy.
Not all alien species establish and spread with negative impacts on biodiversity, local ecosystems and species, but a significant proportion do – then becoming known as invasive alien species.
About 6% of alien plants; 22% of alien invertebrates; 14% of alien vertebrates; and 11% of alien microbes are known to be invasive, posing major risks to nature and to people, the IPBES has said.
The report further noted that many invasive alien species have been intentionally introduced for their perceived benefits, “without consideration or knowledge of their negative impacts’’ – in forestry, agriculture, horticulture, aquaculture, or as pets.
Nearly 80% of the documented impacts of invasive species on nature’s contribution to people are negative.
The water hyacinth is the world’s most widespread invasive alien species on land. Lantana, a flowering shrub, and the black rat are the second and third most widespread globally. The brown rat and the house mouse are also widespread invasive alien species.
The report said that the annual costs of invasive alien species have at least quadrupled every decade since 1970, as global trade and human travel increased. In 2019, the global economic cost of invasive alien species exceeded $423 billion annually.
These trends are projected to accelerate as the global economy expands, land and seas are used more intensively, and demographic change takes place, the report said.
Invasive alien specieslike Aedes albopictus and Aedes aegyptii spread diseases such as malaria, Zika and West Nile Fever, while others also have an impact on livelihood such as the water hyacinth in Lake Victoria in East Africa led to the depletion of tilapia, impacting local fisheries.
The IPBES report has further warned thatwarming temperatures and climate change could favour the “expansion of invasive species’’.
Flashback
The IPBES released its report following a week- long plenary from 28th August, with representatives of the 143 member States which have approved the report.
IPBES is an independent intergovernmental body established to strengthen the science-policy interface for biodiversity and ecosystem services, working in a similar way to the IPCC, which is the UN’s climate science body.
The study, which has taken place over a period of four years, has been by 86 leading experts from 49 countries, drawing on more than 13,000 references.
#upsc #news #headline #IPBES #biodiversity #loss #enviroment #alien #species #ecosystem #biomes #animals #climate #pollution #chnage #lantana #housemouse #hyacinth #travel