See this Video on NDTV: http://www.ndtv.com/news/sci-tech/chandrayaan_discovers_water_on_moon.php
http://timesofindia.indiatimes.com/news/india/One-big-step-for-India-a-giant-leap-for-mankind/articleshow/5053202.cms
One big step for India, a giant leap for mankind
Srinivas Laxman & Prashanth G N, TNN 25 September 2009, 12:47am IST
BANGALORE/MUMBAI: It is a giant leap for India's space programme and the biggest scientific discovery of the 21st Century. India's maiden moon mission, Chandrayaan-1 has found water, a discovery that scientists say will upend thinking about space and boost research. And, of course, it has helped shake off the failure tag from the Rs 386-crore Chandrayaan-I project that was aborted last month.
The historic development, that TOI in a global newsbreak reported in Wednesday's edition, took place just prior to the termination of the mission on August 30, 2009. Although water was spotted by the Moon Mineralogy Mapper (M3), a NASA probe and one of the 11 payloads on the spacecraft, glory shone on ISRO for the discovery that was made after nearly five decades of lunar exploration by Western nations.
``If it weren't for them (ISRO), we wouldn't have been able to make this discovery,'' Carle Pieters, the Brown University researcher who analyzed the data from the NASA probe.
Pieters, a planetary geologist, has told scientists the discovery ``opens a whole new avenue of lunar research but that we have to understand the physics of it to utilize it''. A Brown University statement on Thursday said, ``The discovery by M3 promises to reinvigorate studies of the moon and potentially upend thinking of how it originated.''
Water molecules (H20) and hydroxyl ^ a charged molecule consisting of one oxygen atom and one hydrogen atom ^ were discovered across the surface of the Moon. The M3 had covered almost 97% of the Moon before Chandrayaan-1 was terminated.
Brown University scientists say that while the abundance is not precisely known, ``as much as 1,000 water molecule parts-per-million could be in the lunar soil: harvesting one tonne of the top layer of the Moon's surface would yield as much as 32 ounces of water''.
ISRO chairman Madhavan Nair described it a path-breaking event and Chandrayaan-I project director Mylswamy Annadurai called it one of the greatest examples in international collaboration in space.
Chandrayaan's surprise find triggered tremendous excitement among Indian space scientists who were disappointed that the mission had to be terminated because of a communication breakdown.
Narendra Bhandari, who is associated with Chandrayaan, told TOI from Ahmedabad: ``It is a good observation and after all it was one of the main aims of the Indian Moon programme. According to well-known astrophysicist, S M Chitre, water on the Moon could have been deposited by the comets several billion years ago. ``The comets are like water carriers,'' he told TOI.
Regarding the significance of the discovery, Chitre said that it will have far reaching consequences with regard to the human colonization of the Moon and future rocket launches from the lunar surface. ``The real significance of this mission is that it surveyed the entire moon. Nasa's Apollo manned missions between 1969 and 1972 did not find any water at all because they surveyed only a bare 25% of the lunar surface,'' he said.
President of National Space Society (NSS), Suresh Naik, told TOI finding water will help in making rocket fuel.
``Launching rockets from the Moon definitely have an advantage because the escape velocity is much less than on Earth,'' he said. On Earth, the escape velocity, ie, the speed a rocket needs to escape the Earth's gravity, is 11km per second. With the Moon's gravity being one-sixth that of the Earth's, the escape velocity would be much less, he explained. In plain terms, it means less energy is needed to launch rockets from the Moon.
The US, Russia and China are exploring the possibility of building human habitats on the Moon after 2020. Space experts said that in this race, India cannot lag behind and Isro officials also have not ruled this out.
Pieters said findings from M3 reveal new questions about ``where the water molecules come from and where they may be going''. Scientists have for long speculated that water molecules may migrate from non-polar regions of the Moon to the poles, where they are stored as ice in ultra-frigid pockets of craters that never receive sunlight. If, indeed, the water molecules are mobile, there is then the possibility of getting water to the permanently shadowed craters. She said: ``When we say water on the Moon, we are not talking about lakes, oceans or even puddles. Water on the Moon means molecules of water and hydroxyl that interact with molecules of rock and dust specifically in the top millimeters of the Moon's surface,'' she explained. The M3 team found water molecules and hydroxyl at diverse areas of the sunlit region of the Moon's surface as well as at the Moon's higher latitudes where it seemed more definitive in presence. The M3 discovery has been confirmed by data from two NASA spacecrafts ^ the Visual and Infrared Mapping Spectrometer (VIMS) ^ on the Cassini spacecraft and High-Resolution Infrared Imaging Spectrometer on the EPOXI spacecraft.
The M3 is a joint project of Nasa's Propulsion Laboratory (JPL) and Brown University.
http://www.indianexpress.com/news/kalam-advises-isro-nasa-on-chandrayaanii/521893/
The Indian Space Research Organisation (ISRO) and US space agency NASA should deploy surface robotic penetrator in 'Chandrayaan-II' mission to study more about the presence of water molecules on moon, former President APJ Abdul Kalam has suggested.
"I suggested to both ISRO and NASA to work on future mission of Chandrayaan-II using moon surface robotic penetrator during my recent visit to California Institute of Technology in US, where NASA scientists presented the findings of Moon Mineralogy Mapper (M3) to Indian scientists," Kalam told students during an interaction on Saturday.
29 September 2009
26 September 2009
Asteroid attack: Putting Earth's defences to the test
From: http://www.newscientist.com/article/mg20327271.300-asteroid-attack-putting-earths-defences-to-the-test.html
(See the outstanding video)
http://www.newscientist.com/articlevideo/mg20327271.300/41841503001-asteroid-attack-putting-earths-defences-to-the-test.html
IT LOOKS inconsequential enough, the faint little spot moving leisurely across the sky. The mountain-top telescope that just detected it is taking it very seriously, though. It is an asteroid, one never seen before. Rapid-survey telescopes discover thousands of asteroids every year, but there's something very particular about this one. The telescope's software decides to wake several human astronomers with a text message they hoped they would never receive. The asteroid is on a collision course with Earth. It is the size of a skyscraper and it's big enough to raze a city to the ground. Oh, and it will be here in three days.
Far-fetched it might seem, but this scenario is all too plausible. Certainly it is realistic enough that the US air force recently brought together scientists, military officers and emergency-response officials for the first time to assess the nation's ability to cope, should it come to pass.
They were asked to imagine how their respective organisations would respond to a mythical asteroid called Innoculatus striking the Earth after just three days' warning. The asteroid consisted of two parts: a pile of rubble 270 metres across which was destined to splash down in the Atlantic Ocean off the west coast of Africa, and a 50-metre-wide rock heading, in true Hollywood style, directly for Washington DC.
The exercise, which took place in December 2008, exposed the chilling dangers asteroids pose. Not only is there no plan for what to do when an asteroid hits, but our early-warning systems - which could make the difference between life and death - are woefully inadequate. The meeting provided just the wake-up call organiser Peter Garreston had hoped to create. He has long been concerned about the threat of an impact. "As a taxpayer, I would appreciate my air force taking a look at something that would be certainly as bad as nuclear terrorism in a city, and potentially a civilisation-ending event," he says.
The latest space rock to put the frighteners on us was 2008 TC3. This car-sized object exploded in the atmosphere over Sudan in October last year. A telescope first spotted it just 20 hours before impact - at a distance of 500,000 kilometres - and astronomers say we were lucky to get any warning at all.
Thankfully, 2008 TC3 was far too small to do any damage on the ground, but we are nearly as blind to objects big enough to do serious harm. We have barely begun to track down the millions of skyscraper-sized asteroids zipping around Earth's neighbourhood, any one of which could unleash as much destructive power as a nuclear bomb on impact.
Asteroid impacts are not as rare as you might think. It is widely accepted that an asteroid or comet 30 to 50 metres across exploded over Tunguska in Siberia in 1908, flattening trees for dozens of kilometres all around. The chance of a similar impact is about 1 in 500 each year (Nature, vol 453, p 1178). Put another way, that's a 10 per cent chance of an impact in the next 50 years (see "Should we panic?").
"Fifty-metre asteroids scare me to death," says Timothy Spahr, director of the Minor Planet Center in Cambridge, Massachusetts. "I could easily see a 50-metre object hitting in three days causing absolute pandemonium."
During the US air force planning exercise, the participating scientists explained that with so little warning there would be no hope of preventing an impact. Even Innoculatus's smaller 50-metre asteroid would weigh hundreds of thousands of tonnes, requiring an enormous push to change its trajectory appreciably - so much so that detonating a nuke near it in space would not provide a sufficient impulse so late in the game to cause a miss. To deflect an asteroid sufficiently, force would need to be applied years in advance (see "Could we nuke it?").
In fact, it could make things worse by breaking the asteroid into pieces, some of which could be large enough to do damage, and even create a blizzard of meteors that would destroy satellites in Earth orbit.
Panic on the streets
Realistically, though, the nuclear option would not be on the table in the first place: the nuclear-tipped missiles sitting patiently in silos around the world are not designed to track and home in on an asteroid or even survive for more than a few minutes in space. Instead, we would simply have to brace ourselves for the impact.
The good news is that even a little warning makes a big difference, simply because it would allow us to predict the time and location of impact. In the case of 2008 TC3, just a few hours after the asteroid's discovery, NASA scientists completed calculations that predicted an atmospheric plunge over an unpopulated desert area of northern Sudan, with timing accurate to within a minute.
But participants in the planning exercise worried that if an asteroid posing an imminent threat to a populated area were discovered, and the situation were not handled properly, panic and lack of coordination could lead to chaos on the roads.
Spahr was not involved in the exercise, but shares those concerns. "With a three-day warning, you can walk away and be safe. But it scares me, given how poorly we've handled things of this nature in the past," he says, citing the failure to fully evacuate New Orleans ahead of hurricane Katrina in 2005. "I'm picturing people panicking and driving the wrong way on the freeway, screaming 'Oh my god, it's going to kill us!'"
To prevent panic and disorganised movement, it is crucial for authorities to develop an evacuation plan and communicate it to the public as soon as possible after discovery of the dangerous object, since such discoveries are posted automatically online and would cause a media firestorm.
Such measures should ensure the streets would be very quiet as an object such as Innoculatus plunges into the atmosphere and makes its final approach to Washington DC. The compression of the atmosphere in front of the asteroid and friction with the air would cause rapid heating. At lower altitudes, where the air is denser, the heating becomes so intense that the asteroid vaporises and explodes. For the Tunguska event, this happened at about 8 kilometres above ground.
Supersonic shock wave
If you were unfortunate enough to be looking up from directly below, the explosion would be brighter than the sun. The visible and infrared radiation would be strong enough to make anything flammable ignite, says Mark Boslough of Sandia National Laboratory in Livermore, California. "It's like being in a broiler oven," he says. Anyone directly exposed would quickly be very badly burned.
Even before the sound of the blast reaches you, your body would be smashed by a devastating supersonic shock wave as the explosion creates a bubble of high-pressure air that expands faster than the speed of sound. Planetary scientist Jay Melosh of Purdue University in New York once experienced a shock wave from an experiment that exploded 500 tonnes of TNT, a tiny blast in comparison with the blast from an asteroid. "I was standing on top of a hill about 1.5 kilometres away wearing earplugs," he recalls. Melosh says you would see the shockwave in the air due to the way it refracts light. "It's a shimmering bubble," he says. "It spreads out in complete silence until it reaches you, then you hear a double boom."
Melosh was at a safe distance, but at ground zero below an exploding asteroid, the shock wave would be powerful enough to knock down buildings. It would arrive about 30 seconds after the blazing hot flash of light, and could also knock any nearby planes out of the sky, Boslough says. Any surviving buildings would be pummelled by raging winds blowing faster than any hurricane can muster.
Of course, two-thirds of Earth's surface is ocean. While our atmosphere is likely to protect us from asteroids smaller than 100 metres across, anything larger hitting the ocean - including chunks of Innoculatus's rubble pile - would cause a giant splash that could smash coastal buildings with high-speed volleys of water. The tremendous damage and loss of life that would ensue if multiple cities around an ocean basin were flooded led NASA scientists in 2003 to rate ocean impacts by asteroids as far more dangerous than those on or over land.
Recent computer simulations offer some hope, though. They suggest that the monster waves generated by ocean impacts would typically break far from shore, dissipating most of their energy before they could reach cities - unless the impact was very close to the coast, of course. Another ray of hope is that 100-metre asteroids hit Earth only about one-tenth as often as 30-metre objects.
Lasting just one day, the 2008 US air force exercise could barely scratch the surface of the incoming-asteroid problem. Not surprisingly, it discovered that should the nightmare come true, there is no plan for how to coordinate the activities of NASA, emergency planners, the US military and other parts of government. Further planning exercises are needed: the time saved through early preparation will be crucial if an evacuation is ever required at short notice.
Our chance of having any prior warning at all for an approaching 30-metre asteroid is no better than 25 to 35 per cent with existing sky surveillance, calculates astronomer Alan Harris of the Space Science Institute in Boulder, Colorado (see graphic). The sun washes out half of the sky with daylight, blinding us to 50 per cent of threatening objects. Even glare from the moon can hide unwelcome incoming guests.
What's more, two of the world's three leading asteroid surveys are based in Arizona, including the Catalina Sky Survey, which discovered 2008 TC3. The region tends to cloud over between July and September. "Shift 2008 TC3 back to July and forget it. It wouldn't have been seen," says Spahr.
Now picture this ugly scenario, which worried some participants in the air force exercise: an asteroid flies out of nowhere and explodes over a sensitive nuclear-armed region, like South Asia or the Middle East. There's a reasonable chance that such an airburst could be misinterpreted as a nuclear attack. Both produce a bright flash, a blast wave and raging winds.
An asteroid flying out of nowhere and exploding over a sensitive region like the Middle East could be misinterpreted as a nuclear attack
Such concerns were one reason why, when NASA found 2008 TC3 in its sights, it not only issued a press release but also alerted the US State Department, military commanders, and White House officials, says Lindley Johnson at NASA headquarters, who oversees the agency's work on near-Earth objects. "If it had been going down in the middle of the Pacific somewhere, we probably would not have worried too much more about it, but since it was [going to be] on land and near the Middle East, we did our full alerting," he says.
There is one major way to improve our prospects - point more eyes at the skies. The European Space Agency wants to get into the monitoring game and may set its telescopes at the European Southern Observatory in Chile on the problem. This could fill a gap in the NASA-funded surveys, which are limited to watching the skies of the northern hemisphere, says Richard Crowther of the UK's Science and Technology Facilities Council, who is a consultant for ESA and heads a United Nations working group on near-Earth objects.
Be prepared
"Up to now, the US has taken the majority of the responsibility for dealing with this issue and I think it's time for other states to take on a more equitable share of that," he says.
Help will also come from two new US observatories designed to survey the entire sky visible from their locations every few days. The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), will consist of four 1.8-metre telescopes, the first of which is already up and running in Hawaii. Plans are afoot to construct the 8.4-metre Large Synoptic Survey Telescope in Chile by 2015, though the project is still raising funds. These will improve the chances of an early detection and potentially extend warning times for 30-metre objects to more than a month. But even so, every ground-based lookout suffers from interference from the sun and moon.
A dedicated space telescope would fix this problem, but such a mission could cost more than a billion dollars. "We're talking about investing in an insurance policy," says Irwin Shapiro of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
Shapiro is leading a US National Research Council panel that by year's end will recommend a strategy to better address the threat from near-Earth objects. That study, along with the air force's report on its asteroid impact exercise, is intended to help the White House develop an official policy on the near-Earth object hazard by October 2010, which Congress has requested.
While asteroid impacts are much rarer than hurricanes and earthquakes, they have the potential to do much greater damage, Johnson warns: "It's not something I think there needs to be billions of dollars per year spent on, but it does warrant some priority in the list of things that we ought to be worried about." The cash would at least give us a better idea of when the next asteroid might strike. "From what we know today," he says, "it could be next week."
Should we panic?
An asteroid blast like the one that flattened Tunguska in Siberia in 1908 is expected only once every 500 years or so, on average. It is likely to be a lot longer than that before one hits a populated area, given how small a fraction of Earth's surface is taken up by cities and towns. A NASA study in 2003 concluded that only one in four Tunguska-like impacts would kill anyone, and only one in 17 such impacts would have a death toll of 10,000 or more, comparable to severe earthquakes and tsunamis.
Can we nuke it?
The fastest way to deflect an asteroid away from Earth would be to send a nuclear bomb aboard a spacecraft, à la the film Deep Impact, though we'd still need several years' warning.
The spacecraft would have to be able to home in on the asteroid and to trigger the explosion at just the right distance. Precision is needed to avoid breaking up the hurtling rock while still giving it enough of a nudge to prevent the Earth impact years down the line.
That assumes we're already prepared. Designing and building new spacecraft typically takes a few years. With current rocket technology, it would probably take several additional years to reach a threatening asteroid. And since the explosion would need to occur years ahead of the predicted impact in order to make the asteroid miss Earth, we'd need decades of lead time if we hoped to deflect Armageddon. A confounding factor is that nukes in space are forbidden by the Outer Space Treaty of 1967, signed by the US, Russia, and other nuclear powers, though they might agree to turn a blind eye on this one.
With several decades of warning time, other deflection technologies could come into play. The gravity tractor, for example, would see a spacecraft hover near the asteroid for several years, gradually pulling the asteroid off its collision course using the tiny gravitational pull of the spacecraft's mass.
Another option would be to focus sunlight on a spot on the asteroid using a fleet of mirror-bearing spacecraft, heating it enough to vaporise rock. The escaping gases would act like the exhaust from a rocket engine, giving the asteroid a slight push in the opposite direction that could produce a substantial course change over many years.
David Shiga is New Scientist's physical sciences reporter in Boston
Find the Air Force Report Here:
http://www.nss.org/resources/library/planetarydefense/index.htm
(See the outstanding video)
http://www.newscientist.com/articlevideo/mg20327271.300/41841503001-asteroid-attack-putting-earths-defences-to-the-test.html
IT LOOKS inconsequential enough, the faint little spot moving leisurely across the sky. The mountain-top telescope that just detected it is taking it very seriously, though. It is an asteroid, one never seen before. Rapid-survey telescopes discover thousands of asteroids every year, but there's something very particular about this one. The telescope's software decides to wake several human astronomers with a text message they hoped they would never receive. The asteroid is on a collision course with Earth. It is the size of a skyscraper and it's big enough to raze a city to the ground. Oh, and it will be here in three days.
Far-fetched it might seem, but this scenario is all too plausible. Certainly it is realistic enough that the US air force recently brought together scientists, military officers and emergency-response officials for the first time to assess the nation's ability to cope, should it come to pass.
They were asked to imagine how their respective organisations would respond to a mythical asteroid called Innoculatus striking the Earth after just three days' warning. The asteroid consisted of two parts: a pile of rubble 270 metres across which was destined to splash down in the Atlantic Ocean off the west coast of Africa, and a 50-metre-wide rock heading, in true Hollywood style, directly for Washington DC.
The exercise, which took place in December 2008, exposed the chilling dangers asteroids pose. Not only is there no plan for what to do when an asteroid hits, but our early-warning systems - which could make the difference between life and death - are woefully inadequate. The meeting provided just the wake-up call organiser Peter Garreston had hoped to create. He has long been concerned about the threat of an impact. "As a taxpayer, I would appreciate my air force taking a look at something that would be certainly as bad as nuclear terrorism in a city, and potentially a civilisation-ending event," he says.
The latest space rock to put the frighteners on us was 2008 TC3. This car-sized object exploded in the atmosphere over Sudan in October last year. A telescope first spotted it just 20 hours before impact - at a distance of 500,000 kilometres - and astronomers say we were lucky to get any warning at all.
Thankfully, 2008 TC3 was far too small to do any damage on the ground, but we are nearly as blind to objects big enough to do serious harm. We have barely begun to track down the millions of skyscraper-sized asteroids zipping around Earth's neighbourhood, any one of which could unleash as much destructive power as a nuclear bomb on impact.
Asteroid impacts are not as rare as you might think. It is widely accepted that an asteroid or comet 30 to 50 metres across exploded over Tunguska in Siberia in 1908, flattening trees for dozens of kilometres all around. The chance of a similar impact is about 1 in 500 each year (Nature, vol 453, p 1178). Put another way, that's a 10 per cent chance of an impact in the next 50 years (see "Should we panic?").
"Fifty-metre asteroids scare me to death," says Timothy Spahr, director of the Minor Planet Center in Cambridge, Massachusetts. "I could easily see a 50-metre object hitting in three days causing absolute pandemonium."
During the US air force planning exercise, the participating scientists explained that with so little warning there would be no hope of preventing an impact. Even Innoculatus's smaller 50-metre asteroid would weigh hundreds of thousands of tonnes, requiring an enormous push to change its trajectory appreciably - so much so that detonating a nuke near it in space would not provide a sufficient impulse so late in the game to cause a miss. To deflect an asteroid sufficiently, force would need to be applied years in advance (see "Could we nuke it?").
In fact, it could make things worse by breaking the asteroid into pieces, some of which could be large enough to do damage, and even create a blizzard of meteors that would destroy satellites in Earth orbit.
Panic on the streets
Realistically, though, the nuclear option would not be on the table in the first place: the nuclear-tipped missiles sitting patiently in silos around the world are not designed to track and home in on an asteroid or even survive for more than a few minutes in space. Instead, we would simply have to brace ourselves for the impact.
The good news is that even a little warning makes a big difference, simply because it would allow us to predict the time and location of impact. In the case of 2008 TC3, just a few hours after the asteroid's discovery, NASA scientists completed calculations that predicted an atmospheric plunge over an unpopulated desert area of northern Sudan, with timing accurate to within a minute.
But participants in the planning exercise worried that if an asteroid posing an imminent threat to a populated area were discovered, and the situation were not handled properly, panic and lack of coordination could lead to chaos on the roads.
Spahr was not involved in the exercise, but shares those concerns. "With a three-day warning, you can walk away and be safe. But it scares me, given how poorly we've handled things of this nature in the past," he says, citing the failure to fully evacuate New Orleans ahead of hurricane Katrina in 2005. "I'm picturing people panicking and driving the wrong way on the freeway, screaming 'Oh my god, it's going to kill us!'"
To prevent panic and disorganised movement, it is crucial for authorities to develop an evacuation plan and communicate it to the public as soon as possible after discovery of the dangerous object, since such discoveries are posted automatically online and would cause a media firestorm.
Such measures should ensure the streets would be very quiet as an object such as Innoculatus plunges into the atmosphere and makes its final approach to Washington DC. The compression of the atmosphere in front of the asteroid and friction with the air would cause rapid heating. At lower altitudes, where the air is denser, the heating becomes so intense that the asteroid vaporises and explodes. For the Tunguska event, this happened at about 8 kilometres above ground.
Supersonic shock wave
If you were unfortunate enough to be looking up from directly below, the explosion would be brighter than the sun. The visible and infrared radiation would be strong enough to make anything flammable ignite, says Mark Boslough of Sandia National Laboratory in Livermore, California. "It's like being in a broiler oven," he says. Anyone directly exposed would quickly be very badly burned.
Even before the sound of the blast reaches you, your body would be smashed by a devastating supersonic shock wave as the explosion creates a bubble of high-pressure air that expands faster than the speed of sound. Planetary scientist Jay Melosh of Purdue University in New York once experienced a shock wave from an experiment that exploded 500 tonnes of TNT, a tiny blast in comparison with the blast from an asteroid. "I was standing on top of a hill about 1.5 kilometres away wearing earplugs," he recalls. Melosh says you would see the shockwave in the air due to the way it refracts light. "It's a shimmering bubble," he says. "It spreads out in complete silence until it reaches you, then you hear a double boom."
Melosh was at a safe distance, but at ground zero below an exploding asteroid, the shock wave would be powerful enough to knock down buildings. It would arrive about 30 seconds after the blazing hot flash of light, and could also knock any nearby planes out of the sky, Boslough says. Any surviving buildings would be pummelled by raging winds blowing faster than any hurricane can muster.
Of course, two-thirds of Earth's surface is ocean. While our atmosphere is likely to protect us from asteroids smaller than 100 metres across, anything larger hitting the ocean - including chunks of Innoculatus's rubble pile - would cause a giant splash that could smash coastal buildings with high-speed volleys of water. The tremendous damage and loss of life that would ensue if multiple cities around an ocean basin were flooded led NASA scientists in 2003 to rate ocean impacts by asteroids as far more dangerous than those on or over land.
Recent computer simulations offer some hope, though. They suggest that the monster waves generated by ocean impacts would typically break far from shore, dissipating most of their energy before they could reach cities - unless the impact was very close to the coast, of course. Another ray of hope is that 100-metre asteroids hit Earth only about one-tenth as often as 30-metre objects.
Lasting just one day, the 2008 US air force exercise could barely scratch the surface of the incoming-asteroid problem. Not surprisingly, it discovered that should the nightmare come true, there is no plan for how to coordinate the activities of NASA, emergency planners, the US military and other parts of government. Further planning exercises are needed: the time saved through early preparation will be crucial if an evacuation is ever required at short notice.
Our chance of having any prior warning at all for an approaching 30-metre asteroid is no better than 25 to 35 per cent with existing sky surveillance, calculates astronomer Alan Harris of the Space Science Institute in Boulder, Colorado (see graphic). The sun washes out half of the sky with daylight, blinding us to 50 per cent of threatening objects. Even glare from the moon can hide unwelcome incoming guests.
What's more, two of the world's three leading asteroid surveys are based in Arizona, including the Catalina Sky Survey, which discovered 2008 TC3. The region tends to cloud over between July and September. "Shift 2008 TC3 back to July and forget it. It wouldn't have been seen," says Spahr.
Now picture this ugly scenario, which worried some participants in the air force exercise: an asteroid flies out of nowhere and explodes over a sensitive nuclear-armed region, like South Asia or the Middle East. There's a reasonable chance that such an airburst could be misinterpreted as a nuclear attack. Both produce a bright flash, a blast wave and raging winds.
An asteroid flying out of nowhere and exploding over a sensitive region like the Middle East could be misinterpreted as a nuclear attack
Such concerns were one reason why, when NASA found 2008 TC3 in its sights, it not only issued a press release but also alerted the US State Department, military commanders, and White House officials, says Lindley Johnson at NASA headquarters, who oversees the agency's work on near-Earth objects. "If it had been going down in the middle of the Pacific somewhere, we probably would not have worried too much more about it, but since it was [going to be] on land and near the Middle East, we did our full alerting," he says.
There is one major way to improve our prospects - point more eyes at the skies. The European Space Agency wants to get into the monitoring game and may set its telescopes at the European Southern Observatory in Chile on the problem. This could fill a gap in the NASA-funded surveys, which are limited to watching the skies of the northern hemisphere, says Richard Crowther of the UK's Science and Technology Facilities Council, who is a consultant for ESA and heads a United Nations working group on near-Earth objects.
Be prepared
"Up to now, the US has taken the majority of the responsibility for dealing with this issue and I think it's time for other states to take on a more equitable share of that," he says.
Help will also come from two new US observatories designed to survey the entire sky visible from their locations every few days. The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), will consist of four 1.8-metre telescopes, the first of which is already up and running in Hawaii. Plans are afoot to construct the 8.4-metre Large Synoptic Survey Telescope in Chile by 2015, though the project is still raising funds. These will improve the chances of an early detection and potentially extend warning times for 30-metre objects to more than a month. But even so, every ground-based lookout suffers from interference from the sun and moon.
A dedicated space telescope would fix this problem, but such a mission could cost more than a billion dollars. "We're talking about investing in an insurance policy," says Irwin Shapiro of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
Shapiro is leading a US National Research Council panel that by year's end will recommend a strategy to better address the threat from near-Earth objects. That study, along with the air force's report on its asteroid impact exercise, is intended to help the White House develop an official policy on the near-Earth object hazard by October 2010, which Congress has requested.
While asteroid impacts are much rarer than hurricanes and earthquakes, they have the potential to do much greater damage, Johnson warns: "It's not something I think there needs to be billions of dollars per year spent on, but it does warrant some priority in the list of things that we ought to be worried about." The cash would at least give us a better idea of when the next asteroid might strike. "From what we know today," he says, "it could be next week."
Should we panic?
An asteroid blast like the one that flattened Tunguska in Siberia in 1908 is expected only once every 500 years or so, on average. It is likely to be a lot longer than that before one hits a populated area, given how small a fraction of Earth's surface is taken up by cities and towns. A NASA study in 2003 concluded that only one in four Tunguska-like impacts would kill anyone, and only one in 17 such impacts would have a death toll of 10,000 or more, comparable to severe earthquakes and tsunamis.
Can we nuke it?
The fastest way to deflect an asteroid away from Earth would be to send a nuclear bomb aboard a spacecraft, à la the film Deep Impact, though we'd still need several years' warning.
The spacecraft would have to be able to home in on the asteroid and to trigger the explosion at just the right distance. Precision is needed to avoid breaking up the hurtling rock while still giving it enough of a nudge to prevent the Earth impact years down the line.
That assumes we're already prepared. Designing and building new spacecraft typically takes a few years. With current rocket technology, it would probably take several additional years to reach a threatening asteroid. And since the explosion would need to occur years ahead of the predicted impact in order to make the asteroid miss Earth, we'd need decades of lead time if we hoped to deflect Armageddon. A confounding factor is that nukes in space are forbidden by the Outer Space Treaty of 1967, signed by the US, Russia, and other nuclear powers, though they might agree to turn a blind eye on this one.
With several decades of warning time, other deflection technologies could come into play. The gravity tractor, for example, would see a spacecraft hover near the asteroid for several years, gradually pulling the asteroid off its collision course using the tiny gravitational pull of the spacecraft's mass.
Another option would be to focus sunlight on a spot on the asteroid using a fleet of mirror-bearing spacecraft, heating it enough to vaporise rock. The escaping gases would act like the exhaust from a rocket engine, giving the asteroid a slight push in the opposite direction that could produce a substantial course change over many years.
David Shiga is New Scientist's physical sciences reporter in Boston
Find the Air Force Report Here:
http://www.nss.org/resources/library/planetarydefense/index.htm
19 September 2009
The Sky is Falling Now
http://ieet.org/index.php/IEET/more/brownfield20090917/
Dale Brownfield of Gaia Shield Group agrues for the need for funding, and apprehending the true threat:
Every asteroid that will ever strike Earth is already out there and already on course to strike Earth. Every future asteroid impact event is already an event in progress.
This note is in reply to Mike Treder’s recent article (with which I generally agree) about the threat of near-Earth objects.
Here are my responses to a few of the points made:
You’ll notice, though, that these things happen periodically; not on a regular basis, but every so often…
This seems self contradictory. Periodic means to occur at regular intervals. I think you wanted to say non-periodically, or aperiodically, or at random, without a recursive pattern. Maybe “You’ll notice, though, that these things happen; not on a regular basis, but every so often,” would have been better. However “You’ll notice, though, that these things happen ‘at random’; not on a regular basis, but every so often,” would have been best.
The reason I would pick on this semantic is that the leading astronomy ‘experts’ in this issue have seemed to come to believe in their own intellectual artifacts: population estimates, average relative frequencies, statistical probabilities, power law distribution curves, as if they were hard empirical definitive evidence and not simply academic fabrications. When portrayed to the public or government, the consequence is a gross misapprehension of the threat. Clark Chapman even recently used the phrase ‘known frequency’ in arguing against the possibility of a given large asteroid event 12,000 years ago.
I’m just sayin’, words are symbols for ideas. And here, there has never been a more critical time in the life of mankind for us to get the ideas right.
(If astronomers and aerospace engineers were as sloppy with their mathematical semantics as they are with their linguistic semantics we would still be observing the Sun as it revolved around the Earth.)
...and somewhat predictably. Most of them result from impacts of asteroids or comets. And guess what—those “planet killers” are still out there.
I don’t know what other extinction events you may be referring to here but speaking for asteroid impact events, at least in this context they are wholly unpredictable. In referencing the past occasion of these events or the systemic geometric dynamics of these objects there is no recursive pattern or potential for recursive pattern in their occasion.
The problem with predictability is that every asteroid that will ever strike Earth is already out there and already on course to strike Earth. Every future asteroid impact event is already an event in progress—there is simply nothing to predict! Which and when and how large the next one will be is a never-ending matter of seeing it coming soon enough and with a high enough degree of certainty for us to mount and effective response. The current and proposed observational efforts can only do that as a matter of very good luck.
We can state with absolute certainty that another large impactor will be on a collision course with Earth at some point in the relatively near future. It could be a hundred years from now, a thousand years, a million years, ten million years—or it could be, metaphorically, tomorrow.
Why ‘metaphorically’? Tomorrow is true, precise and literal—and as such the threat is evergreen. If we expect more money from the public and government to address this issue we must scare them better. No Fear = No Funding. No Funding = No Planetary Defense. No Planetary Defense = No More Mankind. This much ain’t rocket science… okay, maybe a little.
Thousands of near-Earth objects (NEOs) are in orbits that bring them into close proximity with the Earth. In addition, there are millions of icy and rocky objects out in the Kuiper belt, any one of which could be jostled from its orbit and sent plummeting toward the Earth at any time. It is estimated that at least 70,000 of these objects are more than 100 km in diameter, large enough to cause the next major extinction event.
Deflecting impending comet impact threats (Oort Cloud/Kuiper Belt Objects) would be virtually impossible from Earth. Perhaps from the orbit of Mars—and at 100 km, not without something a lot bigger than nukes. Probably why none of the proposed discovery surveys even try to look for comets. For now, our response to comet impact threats is the same as to the threat of Rogue Black Holes or Gamma Bursts… Hope!
FYI: At 25 meters (the floor of the threat/harm threshold) or greater, the estimated NEO asteroid population is ~10 million. And whereas extinction level threats begin at 10 km for asteroids, given their greater velocity it is only 6 km for comets.
However the number of asteroids or comets in itself is strategically irrelevant. After all, how many 10 km asteroids or 6 km comets does it take to constitute one extinction level event?
The search for NEOs can be conducted at relatively low cost, especially if it’s done on a cooperative international basis and involves government, academic, and individual volunteer efforts.
In this context you could say that seeing them coming’individually, a few decades before impact, is as close to predictably as we can get.
I trust you understand that if we are going to respond to this threat, and do so successfully, then the detection element will be only a small fraction of the cost in terms of human endeavor. And that when you say ‘relatively low cost’ it would be relative to the cost of deflection or perhaps relative to the magnitude of the loss of our species due to extinction by NEO.
To attempt to deflect a 10 km asteroid with nuclear ablation today, all things considered, would require 10,000 megatons (twice the worlds current nuclear arsenal) delivered by 1,000 Aries V (on the drawing board) heavy launch vehicles. And through 1,000 launch windows…
We can build more nukes and rockets. But even one launch window is a matter of chance and we would need 1,000 of them. If we are to succeed here we need to build and pre-position such a capability to some circumstellar orbit (orbit of Mars?) before we see it coming. And ‘before’ we see it coming begins… Now! Then we can afford to worry about comets.
(For a 100 km object multiply everything above by 1,000 times.)
Although the odds of detecting and stopping a major comet or asteroid that could threaten civilization are small, they are greater than zero, and the cost of ignoring the search is, well, potentially everything.
If you mean exactly what you say here I agree. I’m just surprised that anyone else would say it!
In other words: As things stand, our failure, so far, to develop our conceptual abilities into manifest capabilities will most likely result in a failure of any effort to respond to and deflect any extinction level threat.
However, if you were in fact somehow referring to some academic random-chance probabilistic assessment of the next extinction level event any time soon, then that would be irrelevant, strategically speaking.
See Mike Treder's article at: http://ieet.org/index.php/IEET/more/3408/
"Although the odds of detecting and stopping a major comet or asteroid that could threaten civilization are small, they are greater than zero, and the cost of ignoring the search is, well, potentially everything.
Roller coaster rides are fun. But when the survival of human—and posthuman—civilization is at stake, it’s imperative that we set a high priority on detecting and then deflecting the next planet killer before it gets here."
17 September 2009
Analyst Sees ULA Papers As "Final Nails" For Constellation.
In an article for Popular Mechanics (9/14), aerospace analyst Rand Simberg discussed the set of white papers that the United Launch Alliance will announce at the AIAA Space 2009 conference. According to Simberg, "The papers ULA is presenting this week show the kind of innovation and boldness that NASA has been avoiding." Simberg believes the papers, which propose using fuel depots and the Delta IV and Atlas V launchers instead of NASA's Ares rockets for exploration, "would satisfy some of the requirements of the Aldridge Commission from five years ago in a way that NASA's current Constellation plans never have." They "may well mark the final nails in the Ares and Constellation coffin, signaling that this fall could see yesterday's heresy become tomorrow's new conventional wisdom."
09 September 2009
Augustine Commission Report is Out
Bottom Line:
- Add $3B
- Ditch Ares I, pursue a 140T Ares V Lite, add on-orbit refueling
- Extend ISS to 2020
- Go for Commercial Space Services for Human Access to ISS, On-orbit refueling, etc.
- Follow a Flexible Path of Firsts: Lunar Orbit, LaGrange Points, Asteroid, Mars Moon
Overall, very sane. It preserves heavy launch, establishes human expansion into the solar system as the fundamental goal (which is significant and important). I could only have been happier if it had explicity mentioned Space Solar Power, Planetary Defense, and on the technology side, Re-useable space vehicles and advanced propulsion specifically, as well as resumption of NIAC and BPP activities.
Perhaps, since countries like India are pursuing TSTO and SSTO programs, this new openness to international cooperation could actively engage there even while charting forward with the Ares V Lite.
SUMMARY REPORT
of the
Review of U.S. Human Space Flight Plans Committee
The U.S. human spaceflight program appears to be on an unsustainable trajectory. It is perpetuating the perilous practice of pursuing goals that do not match allocated resources. Space operations are among the most complex and unforgiving pursuits ever undertaken by humans. It really is rocket science. Space operations become all the more difficult when means do not match aspirations. Such is the case today.
The nation is facing important decisions on the future of human spaceflight. Will we leave the close proximity of low-Earth orbit, where astronauts have circled since 1972, and explore the solar system, charting a path for the eventual expansion of human civilization into space? If so, how will we ensure that our exploration delivers the greatest benefit to the nation? Can we explore with reasonable assurances of human safety? And, can the nation marshal the resources to embark on the mission?
Whatever space program is ultimately selected, it must be matched with the resources needed for its execution. How can we marshal the necessary resources? There are actually more options available today than in 1961 when President Kennedy challenged NASA and the nation to “land a man on the Moon by the end of the decade.”
First, space exploration has become a global enterprise. Many nations have aspirations in space, and the combined annual budgets of their space programs are comparable to NASA's. If the United States is willing to lead a global program of exploration, sharing both the burden and benefit of space exploration in a meaningful way, significant benefits could follow. Actively engaging international partners in a manner adapted to today’s multi-polar world could strengthen geopolitical relationships, leverage global resources, and enhance the exploration enterprise.
Second, there is now a burgeoning commercial space industry. If we craft the space architecture to provide opportunities to this industry, there is the potential—not without risk—that the costs to the government would be reduced. Finally, we are also more experienced than in 1961, and able to build on that experience as we design an exploration program. If, after designing cleverly, building alliances with partners, and engaging commercial providers, the nation cannot afford to fund the effort to pursue the goals it would like to embrace, it should accept the disappointment of setting lesser goals.
Can we explore with reasonable assurances of human safety? Human space travel has many benefits, but it is an inherently dangerous endeavor. Human safety can never be absolutely assured, but throughout this report, it is treated as a sine qua non. It is not discussed in extensive detail because any concepts falling short in human safety have simply been eliminated from consideration.
How will we explore to deliver the greatest benefit to the nation? Planning for a human spaceflight program should begin with a choice about its goals—rather than a choice of possible destinations. Destinations should derive from goals, and alternative architectures may be weighed against those goals. There is now a strong consensus in the United States that the next step in human spaceflight is to travel beyond low-Earth orbit. This should carry important benefits to society, including: driving technological innovation; developing commercial industries and important national capabilities; and contributing to our expertise in further exploration. Human exploration can contribute appropriately to the expansion of scientific knowledge, particularly in areas such as field geology, and it is in the interest of both science and human spaceflight that a credible and well-rationalized strategy of coordination between them be developed. Crucially, human spaceflight objectives should broadly align with key national objectives.
Key Questions to Guide the Plan for Human Spaceflight
The Committee identified the following questions that, if answered, would form the
basis of a plan for U.S. human spaceflight:
1. What should be the future of the Space Shuttle?
2. What should be the future of the International Space Station (ISS)?
3. On what should the next heavy-lift launch vehicle be based?
4. How should crews be carried to low-Earth orbit?
5. What is the most practicable strategy for exploration beyond low-Earth
orbit?
The Committee considers the framing and answering of these questions individually, and in a consistent way, to be at least as important as their combinations in the integrated options for a human spaceflight program.
These more tangible benefits exist within a larger context. Exploration provides an opportunity to demonstrate space leadership while deeply engaging international partners; to inspire the next generation of scientists and engineers; and to shape human perceptions of our place in the universe. The Committee concluded that the ultimate goal of human exploration is to chart a path for human expansion into the solar system. This is an ambitious goal, but one worthy of U.S. leadership in concert with a broad range of international partners.
The Committee’s task was to review the U.S. plans for human spaceflight. In doing so, it assessed the programs within the current human spaceflight portfolio; considered capabilities and technologies a future program might require; and considered the roles of commercial industry and our international partners in this enterprise. From these deliberations, the Committee developed five integrated alternatives for the U.S. human spaceflight program. The considerations and the five alternatives are summarized in the pages that follow.
1.0 CURRENT PROGRAMS
Before addressing options for the future human exploration program, it is appropriate to discuss the current programs: the Space Shuttle, ISS and Constellation, as well as the looming problem of “the Gap.”
1.1. Space Shuttle
What should be the future of the Space Shuttle? The present plan is to retire it at the end of FY 2010, with its final flight scheduled for the last month of that fiscal year. Although the current Administration has relaxed the requirement to complete the last mission before the end of FY 2010, there are no funds in the FY 2011 budget for continuing Shuttle operations.
In considering the future of the Shuttle, the Committee assessed the realism of the current schedule; examined issues related to Shuttle workforce, reliability and cost; and weighed the risks and possible benefits of a Shuttle extension. The Committee noted that the projected flight rate is nearly twice that of the actual flight rate since return to flight after the Columbia accident.
Recognizing that undue schedule and budget pressure can subtly impose a negative influence on safety, the Committee finds that a more realistic schedule is prudent. With the remaining flights likely to stretch into the second quarter of 2011, the Committee considers it important to budget for Shuttle operations through that time.
Although a thorough analysis of Shuttle safety was not part of its charter, the Committee did examine the Shuttle’s safety record and reliability. New human-rated launch vehicles will likely be more reliable once they reach maturity, but in the meantime, the Shuttle is in the enviable position of being through its infant mortality phase. Its flight experience and demonstrated reliability should not be discounted.
Once the Shuttle is retired, there will be a gap in America’s capability to launch humans into space. That gap will extend until the next U.S. human-rated launch system becomes available. The Committee estimates that, under the current plan, this gap will be at least seven years long. There has not been this long a gap in U.S. human launch capability since the U.S. human space program began.
Most of the integrated options presented below would retire the Shuttle after a prudent flyout of the current manifest, indicating that the Committee found the interim reliance on international crew services acceptable. However, one option does provide for an extension of Shuttle at a minimum safe flight rate to preserve U.S. capability to launch astronauts into space.
If that option is selected, there should be a thorough review of Shuttle recertification conducted to date and overall Shuttle reliability to ensure that the risk associated with that extension would be acceptable. This review should be performed by an independent committee, with the purpose to ensure that NASA has met the intent behind the relevant recommendation of the Columbia Accident Investigation Board.1
1.2 International Space Station
In considering the future of the International Space Station (ISS), the Committee asked two basic questions: What is the outlook between now and 2015? Should ISS be extended beyond 2015?
1 "Prior to operating the Shuttle beyond 2010, develop and conduct a vehicle recertification at the material, component, subsystem, and system levels. Recertification requirements should be included in the Service Life Extension Program." [Columbia Accident Investigation Board, R9.2-1] Summary Report 4
The Committee is concerned that the ISS, and particularly its utilization, may be vulnerable after Shuttle retirement. ISS was designed, assembled and operated with the capabilities of the Space Shuttle in mind. The present approach to its utilization is based on Shuttle-era experience.
After Shuttle retirement, ISS will rely on a combination of new, and as yet unproven, international and commercial vehicles for cargo transport. Because the planned commercial resupply capability will be crucial to both ISS operations and utilization, it may be prudent to strengthen the incentives to the commercial providers to meet the schedule milestones.
Now that the ISS is nearly completed and is staffed by a full crew of six, its future success will depend on how well it is used. Up to now, the focus has been on assembling ISS, and this has come at the expense of using the Station. Utilization should have first priority in the years ahead.
The Committee finds that the return on investment of ISS to both the United States and the international partners would be significantly enhanced by an extension of ISS life to 2020. It seems unwise to de-orbit the Station after 25 years of assembly and only five years of operational life. Not to extend its operation would significantly impair U.S. ability to develop and lead future international spaceflight partnerships. Further, the ISS should be funded to enable it to achieve its full potential: as the nation’s newest national laboratory, as an enhanced test bed for technologies and operational techniques that support exploration, and as a framework that can support expanded international collaboration.
The strong and tested working relationship among international partners is perhaps the most important outcome of the ISS program. The partnership expresses a “first among equals” U.S. leadership style adapted to today’s multi-polar world. That leadership could extend to exploration, as the ISS partners could engage at an early stage if aspects of exploration beyond low-Earth orbit were included in the goals of the partnership agreement.
1.3 The Constellation Program
The Constellation Program includes: the Ares I launch vehicle, capable of launching astronauts to low-Earth orbit; the Ares V heavy-lift launch vehicle, to send astronauts and equipment to the Moon; the Orion capsule, intended to carry astronauts to low-Earth orbit and beyond; and the Altair lunar lander and lunar surface systems astronauts will need to explore the lunar surface. As the Committee assessed the current status and possible future of the Constellation Program, it reviewed the technical, budgetary and schedule challenges that the program faces today.
Given the funding originally expected, the Constellation Program was a reasonable architecture for human exploration. However, even when it was announced, its budget depended on funds becoming available from the retirement of the Space Shuttle in 2010 and the decommissioning of ISS in early 2016. Since then, as a result of technical and budgetary issues, the development schedules of Ares I and Orion have slipped, and work on Ares V and Altair has been delayed.
Most major vehicle-development programs face technical challenges as a normal part of the process, and Constellation is no exception. While significant, these are engineering problems, and the Committee expects that they can be solved. But these solutions may add to the program’s cost and/or delay its schedule.
The original 2005 schedule showed Ares I and Orion available to support ISS in 2012, only two years after scheduled Shuttle retirement. The current schedule now shows that date as 2015.
An independent assessment of the technical, budgetary and schedule risk to the Constellation Program performed for the Committee indicates that an additional delay of at least two years is likely.2 This means that Ares I and Orion will not reach ISS before the Station’s currently planned termination, and the length of the gap in U.S. ability to launch astronauts into space will be no less than seven years.
The Committee also examined the design and development of Orion. Many concepts are possible for crew-exploration vehicles, and NASA clearly needs a new spacecraft for travel beyond low-Earth orbit. The Committee found no compelling evidence that the current design will not be acceptable for its wide variety of tasks in the exploration program. However, the Committee is concerned about Orion’s recurring costs. The capsule is considerably larger and more massive than previous capsules (e.g., the Apollo capsule), and there is some indication that a smaller and lighter four-person Orion could reduce operational costs. However, a redesign of this magnitude would likely result in over a year of additional development time and a significant increase in cost, so such a redesign should be considered carefully before being implemented.
2.0 CABABILITY FOR LAUNCH TO LOW-EARTH ORBIT AND EXPLORATION BEYOND
2.1 Heavy-Lift Launch to Low-Earth Orbit and Beyond:
No one knows the mass or dimensions of the largest piece that will be required for future exploration missions, but it will likely be significantly larger than 25 metric tons (mt) in launch mass to low-Earth orbit, the capability of current launchers. As the size of the launcher increases, fewer launches and less operational complexity to assemble and/or refuel them results, and the net availability of launch capability increases. Combined with considerations of launch availability and on-orbit operations, the Committee finds that exploration will benefit from the availability of a heavy-lift vehicle. In addition, heavy lift would enable the launching of large scientific observatories and more capable deep-space missions. It may also provide benefit in national security applications. The question is: On what system should the next heavy-lift launch vehicle be based?
Table 2-1. Characteristics of heavy-lift launch vehicles, indicating the EELV and NASA heritage families.
2 The independent assessment was conducted for the Committee by the Aerospace Corporation.
Family Launch Mass to LEO
Ares Ares V + Ares I 160 mt + 25 mt
Family
Ares V Lite 140 mt
NASA
Heritage
Shuttle Derived Family 100 -110 mt
EELV Heritage Family 75 mt
Potential approaches to developing heavy-lift vehicles (Table 2-1) are based on NASA heritage (Shuttle and Apollo) and EELV (evolved expendable launch vehicle) heritage. Each has its distinct advantages and disadvantages.
In the Ares-V-plus-Ares-I system planned by the Constellation program, the Ares I launches the Orion and docks in low-Earth orbit with the Altair lander launched on the Ares V. It has the advantage of projected very high ascent crew safety, but it delays the development of the Ares V heavy lift vehicle until after the independently operated Ares I is developed.
In a different, related architecture, the Orion and Altair are launched on two separate “Lite” versions of the Ares V, providing for more robust mass margins. Building a single NASA vehicle could reduce carrying and operations costs, and accelerate heavy-lift development. Of these two Ares system alternatives, the Committee finds the Ares V Lite in the dual mode the preferred reference option.
The more directly Shuttle-derived family consists of in-line and side-mount vehicles substantially derived from the Shuttle, providing more continuity in workforce. The development cost of the more Shuttle-derived system would be lower, but it would be less capable than the Ares V family and have higher recurring costs. The lower launch capability could eventually be offset by developing on-orbit refueling.
The EELV-heritage systems have the least lift capability, so that to provide equal performance, almost twice as many launches would be required, when compared to the Ares family. If on-orbit refueling were developed and used, the number of launches could be reduced, but
operational complexity would be added. However, the EELV approach would also represent a new way of doing business for NASA, which would have the benefit of potentially lowering development and operational costs. This would come at the cost of ending a substantial portion of the internal NASA capability to develop and operate launchers. It would also require that NASA and the Department of Defense jointly develop the new system.
All of the options would benefit from the development of in-space refueling, and the smaller rockets would benefit most of all. The potential government-guaranteed market for fuel in low-Earth orbit would create a stimulus to the commercial launch industry. In the design of the new launcher, in-space stages and in-space refueling, the Committee cautions against the tradition of designing for ultimate performance, at the cost of reliability, operational efficiency and life-cycle cost.
2.2 Crew Access to Low-Earth Orbit
How should U.S. astronauts be transported to low-Earth orbit? There are two basic
approaches: a government-operated system and a commercial crew-delivery service. The current Constellation Program plan is to use the government-operated Ares I launch vehicle and the Orion crew capsule. However, the Committee found that, because of technical and budget issues, the Ares I schedule no longer supports the ISS.
Ares I was designed to a high standard in order to provide astronauts with access to low-Earth orbit at lower risk and a considerably higher level of reliability than is available today. To achieve this, it uses a high-reliability rocket and a crew capsule with a launch-escape system. But other potential combinations of high-reliability rockets and capsules with escape systems could also provide that reliability. The Committee was unconvinced that enough is known about any of the potential high-reliability launcher-plus-capsule systems to distinguish their levels of safety in a meaningful way.
The United States needs a way to launch astronauts to low-Earth orbit, but it does not necessarily have to be provided by the government. As we move from the complex, reusable Shuttle back to a simpler, smaller capsule, it is an appropriate time to consider turning this transport service over to the commercial sector. This approach is not without technical and programmatic risks, but it creates the possibility of lower operating costs for the system and potentially accelerates the availability of U.S. access to low-Earth orbit by about a year, to 2016. The Committee suggests establishing a new competition for this service, in which both large and small companies could participate.
2.3 Lowering the cost of space exploration
The cost of exploration is dominated by the costs of launch to low-Earth orbit and of the inspace systems. It seems improbable that significant reductions in launch costs will be realized in the short term until launch rates increase substantially—perhaps through expanded commercial activity in space. How can the nation stimulate such activity? In the 1920s, the federal government awarded a series of guaranteed contracts for carrying airmail, stimulating the growth of the airline industry. The Committee concludes that an architecture for exploration employing a similar policy of guaranteed contracts has the potential to stimulate a vigorous and competitive commercial space industry. Such commercial ventures could include supply of cargo to the ISS (already underway), transport of crew to orbit and transport of fuel to orbit. Establishing these commercial opportunities could increase launch volume and potentially lower costs to NASA and all other launch-services customers.
This would have the additional benefit of focusing NASA on a more challenging role, permitting it to concentrate its efforts where its inherent capability resides: for example, developing cutting-edge technologies and concepts, and defining programs and overseeing the development and operation of exploration systems, particularly those beyond low-Earth orbit.
The Committee strongly believes it is time for NASA to reassume its crucial role of developing new technologies for space. Today, the alternatives available for exploration systems are severely limited because of the lack of a strategic investment in technology development in past
decades. NASA now has an opportunity to develop a technology roadmap that is aligned with an exploration mission that will last for decades. If appropriately funded, a technology development program would re-engage the minds at American universities, in industry and within NASA. The investments should be designed to increase the capabilities and reduce the costs of future exploration. This will benefit human and robotic exploration, the commercial space community, and other U.S. government users.
3.0 FUTURE DESTINATIONS FOR EXPLORATION
What is the strategy for exploration beyond low-Earth orbit? Humans could embark on the following paths to explore the inner solar system:
• Mars first, with a Mars landing, perhaps after a brief test of equipment and procedures on the Moon.
• Moon first, with lunar surface exploration focused on developing the capability to explore Mars.
• Flexible path to inner solar system locations, such as lunar orbit, Lagrange points, near- Earth objects and the moons of Mars, followed by exploration of the lunar surface and/or Martian surface.
A human landing followed by an extended human presence on Mars stands prominently above all other opportunities for exploration. Mars is unquestionably the most scientifically interesting destination in the inner solar system, with a history much like Earth’s. It possesses
resources, which can be used for life support and propellants. If humans are ever to live for long periods on another planetary surface, it is likely to be on Mars. But Mars is not an easy place to visit with existing technology and without a substantial investment of resources. The Committee finds that Mars is the ultimate destination for human exploration; but it is not the best first destination.
What about the Moon first, then Mars? By first exploring the Moon, we could develop the operational skills and technology for landing on, launching from and working on a planetary surface. In the process, we could acquire an understanding of human adaptation to another world that would one day allow us to go to Mars.
There are two main strategies for exploring the Moon. Both begin with a few short sorties to various sites to scout the region and validate the lunar landing and ascent systems. In one strategy, the next step would be to build a base. Over many missions, a small colony of habitats would be assembled, and explorers would begin to live there for many months, conducting scientific studies and prospecting for resources that could be used as fuel. In the other strategy, sorties would continue to different sites, spending weeks and then months at each one. More equipment would have to be brought on each trip, but more diverse sites would be explored and in greater detail.
There is a third possible path for human exploration beyond low-Earth orbit, which the Committee calls the Flexible Path. On this path, humans would visit sites never visited before and extend our knowledge of how to operate in space—while traveling greater and greater distances from Earth. Successive missions would visit: lunar orbit; the Lagrange points (special points in space that are important sites for scientific observations and the future space transportation infrastructure); near-Earth objects (asteroids that cross the Earth’s path); and orbit around Mars.
Most interestingly, humans could rendezvous with a moon of Mars, then coordinate with or control robots on the Martian surface.
The Flexible Path represents a different type of exploration strategy. We would learn how to live and work in space, to visit small bodies, and to work with robotic probes on the planetary surface. It would provide the public and other stakeholders with a series of interesting “firsts” to keep them engaged and supportive. Most important, because the path is flexible, it would allow many different options as exploration progresses, including a return to the Moon’s surface, or a continuation to the surface of Mars.
The Committee finds that both Moon First and Flexible Path are viable exploration strategies. It also finds that they are not necessarily mutually exclusive; before traveling to Mars, we might be well served to both extend our presence in free space and gain experience working on the lunar surface.
4.0 INTEGRATED PROGRAM OPTIONS
The Committee has identified five principal alternatives for the human spaceflight program. They include one baseline case, which the Committee believes to be an executable version of the current program of record, funded to achieve its stated exploration goals, as well as four alternatives. These options are summarized in Table 4-1.
Table 4-1. A summary of the integrated program options.
The committee was asked to provide two options that fit within the FY 2010 budget profile. This funding is essentially flat or decreasing through 2014, then increases at 1.4 percent per year thereafter, which is less than the 2.4 percent per year used to estimate cost inflation. The first two options are constrained to that budget.
Option 1. Program of Record as assessed by the Committee, constrained to the FY 2010 budget.
This option is the Program of Record, with only two changes the Committee deems necessary: providing funds for the Shuttle into FY 2011 and including sufficient funds to de-orbit the ISS in 2016. When constrained to this budget profile, Ares I and Orion are not available until after the ISS has been de-orbited. The heavy-lift vehicle, Ares V, is not available until the late 2020s, and worse, there are insufficient funds to develop the lunar lander and lunar surface systems until well into the 2030s, if ever.
Option 2. ISS and Lunar Exploration, constrained to FY 2010 budget. This option extends the ISS to 2020, and it begins a program of lunar exploration using Ares V (Lite). The option assumes Shuttle fly-out in FY 2011, and it includes a technology development program, a program to develop commercial crew services to low-Earth orbit, and funds for enhanced utilization of ISS.
This option does not deliver heavy-lift capability until the late 2020s and does not have funds to develop the systems needed to land on or explore the Moon.
The remaining three alternatives are fit to a different budget profile—one that the Committee judged more appropriate for an exploration program designed to carry humans beyond low-Earth orbit. This budget increases to $3 billion above the FY 2010 guidance by FY 2014, then grows with inflation at a more reasonable 2.4 percent per year.
Option 3. Baseline Case —Implementable Program of Record. This is an executable version of the program of record. It consists of the content and sequence of that program – de-orbiting the ISS in 2016, developing Orion, Ares I and Ares V, and beginning exploration of the Moon. The Committee made only two additions it felt essential: budgeting for the fly-out of the Shuttle in 2011 and including additional funds for ISS de-orbit. The Committee’s assessment is that, under this funding profile, the option delivers Ares1/Orion in FY 2017, with human lunar return in the mid- 2020s.
Option 4. Moon First. This option preserves the Moon as the first destination for human exploration beyond low-Earth orbit. It also extends the ISS to 2020, funds technology advancement, and uses commercial vehicles to carry crew to low-Earth orbit. There are two significantly different variants to this option.
Variant 4A is the Ares Lite variant. This retires the Shuttle in FY 2011 and develops the Ares V (Lite) heavy-lift launcher for lunar exploration. Variant 4B is the Shuttle extension variant. This variant includes the only foreseeable way to eliminate the gap in U.S. human-launch capability: it extends the Shuttle to 2015 at a minimum safe-flight rate. It also takes advantage of synergy with the Shuttle by developing a heavy-lift vehicle that is more directly Shuttle-derived. Both variants of Option 4 permit human lunar return by the mid-2020s.
Option 5. Flexible Path. This option follows the Flexible Path as an exploration strategy. It operates the Shuttle into FY 2011, extends the ISS until 2020, funds technology development and develops commercial crew services to low-Earth orbit. There are three variants within this option; they differ only in the heavy-lift vehicle.
Variant 5A is the Ares Lite variant. It develops the Ares Lite, the most capable of the heavylift vehicles in this option. Variant 5B employs an EELV-heritage commercial heavy-lift launcher and assumes a different (and significantly reduced) role for NASA. It has an advantage of potentially lower operational costs, but requires significant restructuring of NASA. Variant 5C uses a directly Shuttle-derived, heavy-lift vehicle, taking maximum advantage of existing infrastructure, facilities and production capabilities.
All variants of Option 5 begin exploration along the flexible path in the early 2020s, with lunar fly-bys, visits to Lagrange points and near-Earth objects and Mars fly-bys occurring at a rate of about one major event per year, and possible rendezvous with Mars’s moons or human lunar return by the mid to late 2020s.
The Committee has found two executable options that comply with the FY 2010 budget.
However, neither allows for a viable exploration program. In fact, the Committee finds that no plan compatible with the FY 2010 budget profile permits human exploration to continue in any
meaningful way.
The Committee further finds that it is possible to conduct a viable exploration program with a budget rising to about $3 billion annually above the FY 2010 budget profile. At this budget level, both the Moon First strategy and the Flexible Path strategies begin human exploration on a reasonable, though hardly aggressive, timetable. The Committee believes an exploration program that will be a source of pride for the nation requires resources at such a level.
5.0 ORGANIZATIONAL AND PROGRAMMATIC ISSUES
How might NASA organize to explore? The NASA Administrator needs to be given the
authority to manage NASA’s resources, including its workforce and facilities. Even the best managed human spaceflight programs will encounter developmental problems. Such activities must be adequately funded, including reserves to account for the unforeseen and unforeseeable.
Good management is especially difficult when funds cannot be moved from one human spaceflight budget line to another—and where new funds can ordinarily be obtained only after a two-year delay (if at all). NASA should be given the maximum flexibility possible under the law to establish and manage its systems.
Finally, significant space achievements require continuity of support over many years. One way to ensure that no successes are achieved is to continually pull up the flowers to see if the roots are healthy. (This Committee might be accused of being part of this pattern!) NASA and its human spaceflight program are in need of stability in both resources and direction.
6.0 SUMMARY OF KEY FINDINGS
The Committee summarizes its key findings below. Additional findings are included in the body of the report.
The right mission and the right size: NASA’s budget should match its mission and goals.
Further, NASA should be given the ability to shape its organization and infrastructure accordingly, while maintaining facilities deemed to be of national importance.
International partnerships: The U.S. can lead a bold new international effort in the human
exploration of space. If international partners are actively engaged, including on the “critical path” to success, there could be substantial benefits to foreign relations, and more resources overall could become available.
Short-term Space Shuttle planning: The current Shuttle manifest should be flown in a safe and prudent manner. The current manifest will likely extend to the second quarter of FY 2011. It is important to budget for this likelihood.
The human-spaceflight gap: Under current conditions, the gap in U.S. ability to launch astronauts into space will stretch to at least seven years. The Committee did not identify any credible approach employing new capabilities that could shorten the gap to less than six years. The only way to significantly close the gap is to extend the life of the Shuttle Program.
Extending the International Space Station: The return on investment to both the United States and our international partners would be significantly enhanced by an extension of ISS life. Not to extend its operation would significantly impair U.S. ability to develop and lead future international spaceflight partnerships.
Heavy-lift: A heavy-lift launch capability to low-Earth orbit, combined with the ability to inject heavy payloads away from the Earth, is beneficial to exploration, and it also will be useful to the national security space and scientific communities. The Committee reviewed: the Ares family of launchers; more directly Shuttle-derived vehicles; and launchers derived from the EELV family.
Each approach has advantages and disadvantages, trading capability, lifecycle costs, operational complexity and the “way of doing business” within the program and NASA.
Commercial crew launch to low-Earth orbit: Commercial services to deliver crew to low-Earth orbit are within reach. While this presents some risk, it could provide an earlier capability at lower initial and lifecycle costs than government could achieve. A new competition with adequate incentives should be open to all U.S. aerospace companies. This would allow NASA to focus on more challenging roles, including human exploration beyond low-Earth orbit, based on the continued development of the current or modified Orion spacecraft.
Technology development for exploration and commercial space: Investment in a well-designed and adequately funded space technology program is critical to enable progress in exploration.
Exploration strategies can proceed more readily and economically if the requisite technology has been developed in advance. This investment will also benefit robotic exploration, the U.S. commercial space industry and other U.S. government users.
Pathways to Mars: Mars is the ultimate destination for human exploration; but it is not the best first destination. Both visiting the Moon First and following the Flexible Path are viable exploration strategies. The two are not necessarily mutually exclusive; before traveling to Mars, we might be well served to both extend our presence in free space and gain experience working on the lunar surface.
Options for the Human Spaceflight Program: The Committee developed five alternatives for the Human Spaceflight Program. It found:
• Human exploration beyond low-Earth orbit is not viable under the FY 2010 budget guideline.
• Meaningful human exploration is possible under a less constrained budget, ramping to approximately $3 billion per year above the FY 2010 guidance in total resources.
• Funding at the increased level would allow either an exploration program to explore Moon First or one that follows a Flexible Path of exploration. Either could produce results in a reasonable timeframe.
08 September 2009
Obama chan Channel Kennedy by Annoucing SSP
http://www.solar4-energy.com/solar-power/space-based-solar-power
Actually, if Solaren, PowerSat, or other private groups can get 100% of their stuff up from the ground and show a return, it would be a great proof-of-concept for a national effort using private, inter-agency, and multinational partnerships for SBSP using lunar resources. The effort solves the permanent clean energy requirement and the climate problem. It drives the permanent settlement of space. Obama can channel Kennedy by announcing SBSP, which rolls energy and space into one program.
IAA Space Solar Power Conference in Space Canada is On!
The International Academy of Astronautics, the most prestigious global body on Space Issues and Technology has taken up the study of space solar power!
Note also that the ISRO Chairman, Mr. G. Madhavan Nair has been elected the Chairman of the International Academy Astronautics (IAA), the first Indian and the first non-American to hold the post, and will take over 16 Oct (http://www.deccanchronicle.com/national/madhavan-nair-new-head-iaa-844). Already this year, the IAA did the world a tremendous service by publishing (via the support of ISRO) its book, Dealing with the Threat to Earth of Asteroids and Comets, and holding the first international Planetary Defense Conference in Granada, Spain. We can hope for such great support and promotion for Space Solar Power as a solution to the developing and developed world's concerns about energy security and climate change.
Neither India, the US, Canada or China has a program yet that responds to the Japanese $21 Billion program just announced in Space Solar Power.
We just don't know enough about the Comet Threat
A recent article in science magazine (http://www.sciencemag.org/cgi/content/summary/325/5945/1211)suggests there is still a lot to learn about cometary object distributions. Author Martin Duncan states:
Simulations show that the inner Oort Cloud is the source of many more long-period comets
than expected.
The inner Oort Cloud was not previously thought to produce many LPCs, for the following
reason...The object might have spent most of its life in the inner cloud and very recently been nudged into its current (large aphelion) orbit by weak planetary perturbations when its perihelion was drawn in to just beyond the orbit of Saturn (see the fi gure). The simulations of Kaib and Quinn show that a large fraction of the LPCs are generated via this mechanism.
The results of these simulations not only change our view of where the progenitors of
LPCs are stored but may also provide constraints on models of planet formation and on
the properties of the stellar nursery in which the Sun spent its formative years
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