Communities in mountain equatorial regions should be able to provide most of the basic material and energy for launch.  In particular, the [[ram accelerator]] shows promise for providing high accelerations from tubes that, with appropriate engineering[^"Gasdynamic Operation of Baffled Tube Ram Accelerator in Highly Energetic Mixtures", A.J. Higgins, C. Knowlen, C.B. Kiyanda, Submitted to: 20th International Colloquium on the Dynamics of Explosions and Reactive Systems. http://www.galcit.caltech.edu/~jeshep/icders/cd-rom/EXTABS/178_20TH.PDF^] can be made from materials (such as high-grade steel) that are far less exotic than many of those seen in high-performance aerospace applications.  The energy from the byproducts of [[sustainable forestry]], and from using off-peak electricity surpluses from [[small hydro]], [[wind power]] and [[geothermal energy]] should be more than adequate. If the crater of a dormant or extinct volcano considered as a launch point contains a crater lake, the same drilling equipment used to tap geothermal power might be used to bore a "pilot tunnel" from the crater to the base, for small hydro. Development of such energy sources in candidate regions for local community use and for supplying their neighboring communities, should take precedence as a Project focus. The Project would help supply the needed equipment and expertise in exchange for promises of an adequate share of energy, if and when the time comes for projectile launch development.

%rfloat% http://www.aqplink.com/colca/wp-content/uploads/2012/04/condor_colca_2.jpg | ''Respect the current inhabitants, human or not''

%rframe width=45pct% http://www.eurasianet.org/sites/default/files/imagecache/galleria/09.jpg|''[[http://www.eurasianet.org/departments/culture/articles/eav041902.shtml | Scrap Metal Dealers Live Off Falling Rockets]] - Photo credit: Jonas Bendiksen, Laara Matsen''

%lfloat% https://classes.soe.ucsc.edu/ee070/Fall07/UNSECURE/Pictures%20of%20the%20Mass%20Driver%20discussed%20in%20class/mass-driver-2%5B1%5D.gif | ''The L5 Society inspired work on electromagnetic launchers''

[^#^]

[[Project Persephone]]'s focus on aid and development projects in [[equatorial alpine regions]] is strongly motivated by the likelihood that these regions can be made ideal for projectile space launch. Of course, such regions also tend to be relatively undeveloped and energy-poor. Space launch tends to require expensive labor ([[recurring engineering costs]]) from developed countries, and it's also quite energy-intensive. However, some schemes for projectile launch, such as the [[ram accelerator]], could require relatively little energy per unit of mass orbited, and only very simple infrastructure requiring relatively little expert operation and maintenance.

Communities in alpine equatorial regions should be able to provide most of the basic material and energy for launch.  In particular, the [[ram accelerator]] shows promise for providing high accelerations from tubes that, with appropriate engineering[^"Gasdynamic Operation of Baffled Tube Ram Accelerator in Highly Energetic Mixtures", A.J. Higgins, C. Knowlen, C.B. Kiyanda, Submitted to: 20th International Colloquium on the Dynamics of Explosions and Reactive Systems. http://www.galcit.caltech.edu/~jeshep/icders/cd-rom/EXTABS/178_20TH.PDF^] can be made from materials (such as high-grade steel) that are far less exotic than many of those seen in high-performance aerospace applications.  The energy from the byproducts of [[sustainable forestry]], and from using off-peak electricity surpluses from [[small hydro]], [[wind power]] and [[geothermal energy]] should be more than adequate. If the crater of a dormant or extinct volcano considered as a launch point contains a crater lake, the same drilling equipment used to tap geothermal power might be used to bore a "pilot tunnel" from the crater to the base, for small hydro. Development of such energy sources in candidate regions for local community use and for supplying their neighboring communities, should take precedence as a Project focus. The Project would help supply the needed equipment and expertise in exchange for promises of an adequate share of energy, if and when the time comes for projectile launch development.

Air launch reuses the aircraft, but the one system currently in repeated use (the Orbital ATK Pegasus, launched while slung under a Boeing L-1011) isn't particularly cheap. The Space Shuttle was even more reusable -- only the external tanks were discarded. It wasn't cheap either. More recently, SpaceX is able to return lower stages and launch with them again. However, the chief executive of SpaceX has estimated the cost reductions at around 30%. This is not cheaper by a factor of three, or even two, as so many of us had hoped. SpaceX had already demonstrated dramatic cost reductions. But it got these before lower-stage reuse.

The earlier cost reductions at SpaceX appear to have come not from better technology (though there is some), but from two business decisions. One was to organize launcher production largely under a single corporate roof, which enables more "agile" engineering bureaucracy, rather than as a far-flung network of subcontractors as seen in the aerospace incumbents. The other decision was to gain some economies of scale by standardizing on an engine (the most value-added component) that can be used in clusters. Those are good practices. But they aren't new. This is how Russia became the low-cost leader in space launch. And with the uncertainties over whether ''upper'' stages can be economically returned, SpaceX may have reached the point of diminishing returns for cost reductions.

Air launch reuses the aircraft, but the one system currently in repeated use (the Orbital ATK Pegasus, launched while slung under a Boeing L-1011) isn't particularly cheap. The Space Shuttle was even more reusable -- only the external tanks were discarded. It wasn't cheap either. More recently, SpaceX is able to return lower stages and launch with them again. However, the chief executive of SpaceX has estimated the cost reductions at around 30%. This is not cheaper by a factor of three, or even two, as so many of us had hoped. SpaceX has demonstrated dramatic cost reductions. But it got these before lower-stage reuse. The gains appear to come not from better technology (though there is some), but from two business decisions. One was to organize launcher production largely under a single corporate roof, which enables more "agile" engineering bureaucracy, rather than as a far-flung network of subcontractors as seen in the aerospace incumbents. The other decision was to gain some economies of scale by standardizing on an engine (the most value-added component) that can be used in clusters. Those are good practices. But they aren't new. This is how Russia became the low-cost leader in space launch. And with uncertainties over whether ''upper'' stages can be economically returned, the point of diminishing returns for the reducing the cost of sending rockets to orbit may have been reached.

->Orbit-class rocketry involves exotic materials, unusual manufacturing techniques, and relatively low production rates. Low rates of production make achieving economies of scale difficult. Many technicians and engineers end up doing tasks that, if demand were higher, would be economically automated. Exotic materials aren't cheap, almost by the definition of "exotic". Most things we use in daily life and work are engineered with high safety factors (as much as 5x) to avoid liability lawsuits. Our everyday items are also often made with the cheapest materials that will satisfy the customer, and these are often the heavier materials. Doing without high safety factors entails frequent testing and inspection out of concern for failure of materials crafted to somewhere near the limits of their performance. Why not just go with higher safety factors? They usually impose a penalty in mass. And because of what's been called "the tyranny of the rocket equation,"[^"[[https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html | The Tyranny of the Rocket Equation]]", [[https://en.wikipedia.org/wiki/Donald_Pettit | Don Petit]], NASA, 05.01.12^] more mass would mean much larger rockets, and more stages. Trying to make rocket launch cheaper in one category of expense just squeezes expense out into another category. Launcher design is a thicket of trade-offs. It's an unusually complicated thicket. They don't call it rocket science for nothing.

->Note that it's ''recurring'' engineering. A big rocket launch has been compared to building an ocean liner, then scuttling it after it makes one ocean crossing. This observation has been taken as dictating reusability wherever possible. But does reusability make launch to orbit dramatically cheaper? The record so far isn't very encouraging.

->Air launch reuses the aircraft, but the one system currently in repeated use (the Orbital ATK Pegasus, launched while slung under a Boeing L-1011) isn't particularly cheap. The Space Shuttle was even more reusable -- only the external tanks were discarded. It wasn't cheap either. More recently, SpaceX is able to return lower stages and launch with them again. However, the chief executive of SpaceX has estimated the cost reductions at around 30%. This is not cheaper by a factor of three, or even two, as so many of us had hoped. SpaceX has demonstrated dramatic cost reductions. But it got these before lower-stage reuse. The gains appear to come not from better technology (though there is some), but from two business decisions. One was to organize launcher production largely under a single corporate roof, which enables more "agile" engineering bureaucracy, rather than as a far-flung network of subcontractors as seen in the aerospace incumbents. The other decision was to gain some economies of scale by standardizing on an engine (the most value-added component) that can be used in clusters. Those are good practices. But they aren't new. This is how Russia became the low-cost leader in space launch. And with uncertainties over whether ''upper'' stages can be economically returned, the point of diminishing returns for the reducing the cost of sending rockets to orbit may have been reached.

->The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. [^ "Ground-based, hypervelocity accelerators for low-cost delivery of large numbers of small, high-g tolerant payloads to LEO are a near-term technology that can provide significant payoff for a relatively small technology investment." NASA, April 2012. [[http://www.nasa.gov/pdf/500393main_TA01-ID_rev6-NRC-wTASR.pdf | Launch Propulsion Systems Roadmap: Technology Area 01]], p.2^] The global environmental impact should be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot (black carbon), which has high global warming potential (GWP).[^Adam Mann, "[[http://www.nature.com/news/2010/101022/full/news.2010.558.html#B1 | "Space tourism to accelerate climate change"]], 22 October 2010, [[http://en.wikipedia.org/wiki/Nature_(journal) | Nature]], doi:10.1038/news.2010.558^],[^Geophysical Research Letters, v.37, 2010, "[[http://www.agu.org/pubs/crossref/2010/2010GL044548.shtml | Potential climate impact of black carbon emitted by rockets]]", Martin Ross, Michael Mills, Darin Toohey, doi:10.1029/2010GL044548^]

%lfloat% http://photocdn.sohu.com/20080202/Img255041104.jpg | ''U.S. Navy test of a railgun that shoots smart munitions''

%lframe margin-top=5px margin-right=25px margin-bottom=5px margin-left=25px% https://www.nasa.gov/sites/default/files/styles/side_image/public/thumbnails/image/elg_0764_2.jpg | NASA staff inspect ... and inspect ....

%rframe width=45pct% http://www.eurasianet.org/sites/default/files/imagecache/galleria/09.jpg|[[http://www.eurasianet.org/departments/culture/articles/eav041902.shtml | Scrap Metal Dealers Live Off Falling Rockets]] - Photo credit: Jonas Bendiksen, Laara Matsen

%rfloat% https://s-media-cache-ak0.pinimg.com/236x/f0/8b/a3/f08ba3587e3003526f0de796eb6c26d9--spacex-launch-rocket-ships.jpg | First stage return - only 30% cheaper?

%lfloat% https://classes.soe.ucsc.edu/ee070/Fall07/UNSECURE/Pictures%20of%20the%20Mass%20Driver%20discussed%20in%20class/mass-driver-2%5B1%5D.gif | The L5 Society inspired work on hypervelocity electromagnetic launchers

%rfloat% https://i.pinimg.com/236x/85/e4/42/85e442be6e73dca933b99611aa35212b--james-darcy-skiers.jpg | Rocket exhaust: too much soot?

There has been research, even relatively recently, on boosting partly air-breathing spacecraft up to supersonic speeds along more-or-less horizontal tracks, with a view toward eventually hosting man-rated launchers[^"First Stage of a Highly Reliable Reusable Launch System", Kurt J. Kloesel, Jonathan B. Pickrel, Emily L. Sayles, Michael Wright, Darin Marriott, Leo Holland, Stephen Kuznetsov, AIAA 2009-6805. http://pdf.aiaa.org/preview/CDReadyMSPACE09_2074/PV2009_6805.pdf^].  However, Project Persephone doesn't aim for manned launch, which is inevitably expensive.  Instead of relatively low horizontal acceleration as a prelude to hypersonic aerodynamic stages, it looks instead to sites for high-angle, very high acceleration launch from mountain slopes, particularly those of extinct or dormant stratovolcanoes near the equator, obviating the need for complex air-breathing propulsion stages.

A common objection to projectile space launch is that nothing of any complexity could survive it -- at best, it's thought that only bulk materials can be shipped. This isn't true. Complex unpiloted aerial vehicles have been designed that fold into a package formed as a standard 155 mm artillery round, demonstrating in tests that they can function after being subjected to 12,000 g accelerations.[^"Flyer Assembly", Patent No 6,392,213 B1 Issued May 21, 2002 http://www.draper.com/digest03/patent103.pdf^] The payloads required for [[telebots | telebotic]] construction of [[exovivaria]] can be engineered to survive similar launch stresses, if necessary.

%lfloat% https://i.pinimg.com/236x/85/e4/42/85e442be6e73dca933b99611aa35212b--james-darcy-skiers.jpg | Rocket exhaust: too much soot?

%lfloat margin-top=5px margin-right=25px margin-bottom=5px margin-left=25px% https://www.nasa.gov/sites/default/files/styles/side_image/public/thumbnails/image/elg_0764_2.jpg | NASA staff inspect ... and inspect ....

%rfloat width=45pct% http://www.eurasianet.org/sites/default/files/imagecache/galleria/09.jpg |
[[http://www.eurasianet.org/departments/culture/articles/eav041902.shtml | Scrap Metal Dealers Live Off Falling Rockets]] (Photo credit: Jonas Bendiksen, Laara Matsen)

%rfloat% https://s-media-cache-ak0.pinimg.com/236x/f0/8b/a3/f08ba3587e3003526f0de796eb6c26d9--spacex-launch-rocket-ships.jpg | SpaceX saves only about 30% from lower stage return

The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. [^ "Ground-based, hypervelocity accelerators for low-cost delivery of large numbers of small, high-g tolerant payloads to LEO are a near-term technology that can provide significant payoff for a relatively small technology investment." NASA, April 2012. [[http://www.nasa.gov/pdf/500393main_TA01-ID_rev6-NRC-wTASR.pdf | Launch Propulsion Systems Roadmap: Technology Area 01]], p.2^] The global environmental impact should be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot, which has high global warming potential (GWP).[^Adam Mann, "[[http://www.nature.com/news/2010/101022/full/news.2010.558.html#B1 | "Space tourism to accelerate climate change"]], 22 October 2010, [[http://en.wikipedia.org/wiki/Nature_(journal) | Nature]], doi:10.1038/news.2010.558^],[^Geophysical Research Letters, v.37, 2010, "[[http://www.agu.org/pubs/crossref/2010/2010GL044548.shtml | Potential climate impact of black carbon emitted by rockets]]", Martin Ross, Michael Mills, Darin Toohey, doi:10.1029/2010GL044548^]

%lfloat width=45pct% http://www.eurasianet.org/sites/default/files/imagecache/galleria/09.jpg |

Air launch reuses the aircraft, but the one system currently in repeated use (the Orbital ATK Pegasus, launched while slung under a Boeing L-1011) isn't particularly cheap. The Space Shuttle was even more reusable -- only the external tanks were discarded. It wasn't cheap either. More recently, SpaceX is able to return lower stages and launch with them again. However, the chief executive of SpaceX has estimated the cost reductions at around 30%. This is not cheaper by a factor of three, or even two, as so many of us had hoped. SpaceX has demonstrated dramatic cost reductions. But it got these before lower-stage reuse. The gains appear to come not from better technology (though there is some), but from two business decisions. One was to organize launcher production largely under a single corporate roof, which enables more "agile" engineering bureaucracy, rather than as a far-flung network of subcontractors as seen in the aerospace incumbents. The other decision was to gain some economies of scale by standardizing on an engine (the most value-added component) that can be used in clusters. Those are good practices. But they aren't new. This is how Russia became the low-cost leader in space launch. And with uncertainties over whether ''upper'' stages can be economically returned, the point of diminishing returns for the reducing the cost of sending rockets to orbit may have been reached.

Note that it's ''recurring'' engineering. A big rocket launch has been compared to building an ocean liner, then scuttling it after it makes one ocean crossing. This observation has been taken as dictating reusability wherever possible. But does reusability make launch to orbit dramatically cheaper? The record so far isn't very encouraging.

Orbit-class rocketry involves exotic materials, unusual manufacturing techniques, and relatively low production rates. Low rates of production make achieving economies of scale difficult. Many technicians and engineers end up doing tasks that, if demand were higher, would be economically automated. Exotic materials aren't cheap, almost by the definition of "exotic". Most things we use in daily life and work are engineered with high safety factors (as much as 5x) to avoid liability lawsuits. Our everyday items are also often made with the cheapest materials that will satisfy the customer, and these are often the heavier materials. Doing without high safety factors entails frequent testing and inspection out of concern for failure of materials crafted to somewhere near the limits of their performance. Why not just go with higher safety factors? They usually impose a penalty in mass. And because of what's been called "the tyranny of the rocket equation,"[^"[[https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html | The Tyranny of the Rocket Equation]]", [[https://en.wikipedia.org/wiki/Donald_Pettit | Don Petit]], NASA, 05.01.12^] more mass would mean much larger rockets, and more stages. Trying to make rocket launch cheaper in one category of expense just squeezes expense out into another category. Launcher design is a thicket of trade-offs. It's an unusually complicated thicket. They don't call it rocket science for nothing.

Air launch reuses the aircraft, but the one system currently in repeated use (the Orbital ATK Pegasus, launched while slung under a Boeing L-1011) isn't particularly cheap. The Space Shuttle was even more reusable -- only the external tanks were discarded. It wasn't cheap either. More recently, SpaceX is able to return lower stages and launch with them again. However, the chief executive of SpaceX has estimated the cost reductions at around 30%. This is not cheaper by a factor of three, or even two, as so many of us had hoped. SpaceX has demonstrated dramatic cost reductions. But it got these before lower-stage reuse. The gains appear to come not from better technology (though there is some), but from two business decisions. One was to organize launcher production largely under a single corporate roof, which enables more "agile" engineering bureaucracy, rather than as a far-flung network of subcontractors as seen in the aerospace incumbents. The other decision was to gain some economies of scale by standardizing on an engine (the most value-added component) that can be used as clusters. Those are good practices. But they aren't new. This is how Russia became the low-cost leader in space launch. And with uncertainties over whether upper stages can be economically returned, the point of diminishing returns may have been reached.

Orbit-class rocketry involves exotic materials, unusual manufacturing techniques, and relatively low production rates. Low rates of production make achieving economies of scale difficult. Many technicians and engineers end up doing tasks that, if demand were higher, would be economically automated. Exotic materials aren't cheap, almost by the definition of "exotic". Most things we use in daily life and work are engineered with high safety factors (as much as 5x) to avoid liability lawsuits. Our everyday items are also often made with the cheapest materials that will satisfy the customer, and these are often the heavier materials. Doing without high safety factors entails frequent testing and inspection out of concern for failure of materials crafted to somewhere near the edge of their performance. Why not just go with higher safety factors? They usually impose a penalty in mass. And because of what's been called "the tyranny of the rocket equation,"[^"[[https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html | The Tyranny of the Rocket Equation]]", [[https://en.wikipedia.org/wiki/Donald_Pettit | Don Petit]], NASA, 05.01.12^] more mass would mean much larger rockets, and more stages. Trying to make rocket launch cheaper in one category of expense just squeezes expense out into another category. Launcher design is a thicket of trade-offs. It's an unusually complicated thicket. They don't call it rocket science for nothing.

Orbit-class rocketry involves exotic materials, unusual manufacturing and construction techniques, and relatively low production rates. Low rates of production make achieving economies of scale difficult. Many technicians and engineers end up doing tasks that, if demand were higher, would be economically automated. Exotic materials aren't cheap -- almost by the definition of "exotic". Most things we use in daily life and work are engineered with high safety factors (as much as 5x) to avoid liability lawsuits. Our everyday items are also often made with the cheapest materials that will satisfy the customer, and these are often the heavier materials. Doing without high safety factors entails frequent testing and inspection. Why not just go with higher safety factors? They usually impose a penalty in mass. Because of what's been called "the tyranny of the rocket equation,"[^"[[https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html | The Tyranny of the Rocket Equation]]", [[https://en.wikipedia.org/wiki/Donald_Pettit | Don Petit]], NASA, 05.01.12^] more mass would mean much larger rockets, and more stages. Trying to make rocket launch cheaper in one way just squeezes expense out into another category of expense. Launcher design is a thicket of trade-offs. It's an unusually complicated thicket. They don't call it rocket science for nothing.

Note that it's ''recurring'' engineering. This observation has been taken as dictating reusability wherever possible. But is it really cheaper? Air launch reuses the aircraft, but the one system currently in repeated use (the Orbital ATK Pegasus, launched from under a Boeing L-1011) isn't particularly cheap. The Space Shuttle wasn't cheap either. More recently, SpaceX is able to return lower stages, but the chief executive has estimated the cost reductions at around 30%, not the hoped-for 3x. It appears that SpaceX got many of its cost reductions before lower-stage reuse simply by organizing launcher production under one corporate roof, rather than as a far-flung network of subcontractors, and by gaining some economies of scale by standardizing on an engine that can be used as clusters. This isn't new. This is how Russia became the low-cost leader. And the point of diminishing returns may be in sight.

Project Persephone looks in another direction: projectile space launch. In one form, people call this idea "space guns". In another, "mass driver." In any form, it puts most of the apparatus required for acceleration on the ground, where mass doesn't matter very much. Most of what gets put into orbit can be ruggedized for very high accelerations, so the loss is only in not being able to launch people or anything else very delicate.

Putting things into orbit remains expensive. It's been persuasively argued that the dominant cost is labor in expensive forms: ''recurring'' engineering.[^"[[http://home.earthlink.net/~peter.a.taylor/launch.htm | Why Are Launch So High?]]", Peter A. Taylor, March 2000 (last major update September 2004)^] Why is this?

Orbit-class rocketry involves exotic materials, unusual manufacturing and construction techniques, and relatively low production rates. Low rates of production make achieving economies of scale difficult. Many technicians and engineers end up doing tasks that, if demand were higher, would be economically automated. Exotic materials aren't cheap -- almost by the definition of "exotic". And most things we use in daily life and work are engineered with high safety factors (as much as 5x) just to be on the safe side. Our everyday items are also made with the cheapest materials that will satisfy the customer, and these are often the heavier ones. Doing without high safety factors entails frequent testing and inspection. Why not just go with higher safety factors? They usually impose a penalty in mass. Because of what's been called "the tyranny of the rocket equation,"[^"[[https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html | The Tyranny of the Rocket Equation]]", [[https://en.wikipedia.org/wiki/Donald_Pettit | Don Petit]], NASA, 05.01.12^] more mass would mean much larger rockets, and more stages. The expense just squeezes out into another problem area. So, launcher design turns into a thicket of trade-offs. It's an unusually complicated thicket. They don't call it rocket science for nothing.

Putting things into orbit is expensive. It's been persuasively argued that
what dominates the cost is recurring engineering.[^"[[http://home.earthlink.net/~peter.a.taylor/launch.htm | Why Are Launch So High?]]", Peter A. Taylor, March 2000 (last major update September 2004)^] Why is this?

Getting to orbit with rocketry involves exotic materials and construction, at relatively low production rates. Low rates of production make achieving economies of scale difficult. Most things we use in daily life and work are engineered with high safety factors (as much as 5x) just to be on the safe side. Using higher safety factors usually imposes a penalty in mass. because of what's been called "the tyranny of the rocket equation,"[^"[[https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html | The Tyranny of the Rocket Equation]]", [[https://en.wikipedia.org/wiki/Donald_Pettit | Don Petit]], 05.01.12^] more mass would mean larger rockets, and more stages.

The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. [^ "Ground-based, hypervelocity accelerators for low-cost delivery of large numbers of small, high-g tolerant payloads to LEO are a near-term technology that can provide significant payoff for a relatively small technology investment." NASA, April 2012. [[http://www.nasa.gov/pdf/500393main_TA01-ID_rev6-NRC-wTASR.pdf | Launch Propulsion Systems Roadmap: Technology Area 01]], p.2^] The global environmental impact might be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot, which has high global warming potential (GWP).[^Adam Mann, "[[http://www.nature.com/news/2010/101022/full/news.2010.558.html#B1 | "Space tourism to accelerate climate change"]], 22 October 2010, [[http://en.wikipedia.org/wiki/Nature_(journal) | Nature]], doi:10.1038/news.2010.558^],[^Geophysical Research Letters, v.37, 2010, "[[http://www.agu.org/pubs/crossref/2010/2010GL044548.shtml | Potential climate impact of black carbon emitted by rockets]]", Martin Ross, Michael Mills, Darin Toohey, doi:10.1029/2010GL044548^]

[[Project Persephone]]'s focus on aid and development projects in [[equatorial alpine regions]] is strongly motivated by the likelihood that these regions can be made ideal for projectile space launch. Of course, such regions also tend to be relatively undeveloped and energy-poor. Space launch tends to require expensive labor ([[recurring engineering costs]]) from developed countries, and it's also quite energy-intensive.  However, some schemes for projectile launch, such as the [[ram accelerator]], could require relatively little energy per unit of mass orbited, and only very simple infrastructure requiring relatively little expert operation and maintenance.

Communities in alpine equatorial regions might be able to provide most of the basic material and energy for launch.  In particular, the [[ram accelerator]] shows promise for providing high accelerations from tubes that, with appropriate engineering[^"Gasdynamic Operation of Baffled Tube Ram Accelerator in Highly Energetic Mixtures", A.J. Higgins, C. Knowlen, C.B. Kiyanda, Submitted to: 20th International Colloquium on the Dynamics of Explosions and Reactive Systems. http://www.galcit.caltech.edu/~jeshep/icders/cd-rom/EXTABS/178_20TH.PDF^] might be made from materials far less exotic than many of those seen in high-performance aerospace applications.  The energy from the byproducts of [[sustainable forestry]], and using off-peak electricity surpluses from [[small hydro]], [[wind power]] and [[geothermal energy]] might be more than adequate. If the crater of a dormant or extinct volcano considered as a launch point contains a caldera lake, the same drilling equipment used for tapping geothermal sources might be used to bore a "pilot tunnel" from the crater to the base, for small hydro. Development of such energy sources in candidate regions for local community use and for supplying their neighboring communities, should take precedence as a Project focus. The Project would help supply the needed equipment and expertise in exchange for promises of an adequate share of energy, if and when the time comes for projectile launch development.

A common objection to projectile space launch is that nothing of any complexity could survive it -- at best, it's thought that only bulk materials might be shipped.  However, complex unpiloted aerial vehicles have been designed that fold into a package formed as a standard 155 mm artillery round, demonstrating in tests that they can function after being subjected to 12,000 g accelerations.[^"Flyer Assembly", Patent No 6,392,213 B1 Issued May 21, 2002 http://www.draper.com/digest03/patent103.pdf^] The payloads required for [[telebots | telebotic]] construction of [[exovivaria]] can almost certainly be engineered to survive similar launch stresses, if necessary.

Another common objection to projectile space launch is that the vehicles would simply disintegrate in the lower atmosphere.  However, it's been estimated that even low-mass projectiles exiting an accelerator at sea level could survive transit of the atmosphere with less than half of their mass devoted to cooling or ablative shielding.[^http://www.cs.cmu.edu/afs/cs/usr/mnr/st/std027, http://www.tbfg.org/papers/Ram%20Accelerator%20Technical%20Risks%20ISDC07.pdf^].  For larger projectiles at higher altitudes, the mass requirement for thermal protection has been estimated as low as 1% of total mass accelerated.

A more serious objection to projectile space launch from the Earth's surface is environmental: atmospheric shock waves.  The muzzle shock wave from [[light gas guns | light gas gun]] launches at Lawrence Livermore was strong enough to kill nearby plant life. '''(Ref needed)'''  Endangered animal species, such the Andean Condor, might be displaced from some habitats, and significantly disturbed in others.  Sonic booms from the projectile might be very alarming and stressful to people even hundreds of kilometers away.  Careful siting, timing and advance warning might ameliorate the problem to some extent.  With an exit point from a volcano crater, perhaps a significant portion of the shock could be deflected upward; higher launch altitudes would tend to reduce shock intensity; and higher altitudes also correlate with more remote locations, with fewer human and animal inhabitants.  Sonic shock environmental impact is an important criterion for narrowing the choice of sites, and will likely be an ongoing research topic even after likely sites are chosen for preliminary development.

what dominates the cost is recurring engineering.[^"[[http://home.earthlink.net/~peter.a.taylor/launch.htm | Why Are Launch So High?]]", Peter A. Taylor, March 2000 (last major update September 2004)^] Getting to orbit with rocketry involves exotic materials and construction, at relatively low production rates. Most things we use are engineering with high safety factors (as much as 5x) just to be on the safe side. High safety factors impose a penalty in mass, and because of the rocket equation, more mass would mean larger rockets, and more stages.

Putting things into orbit is expensive. The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. [^ "Ground-based, hypervelocity accelerators for low-cost delivery of large numbers of small, high-g tolerant payloads to LEO are a near-term technology that can provide significant payoff for a relatively small technology investment." NASA, April 2012. [[http://www.nasa.gov/pdf/500393main_TA01-ID_rev6-NRC-wTASR.pdf | Launch Propulsion Systems Roadmap: Technology Area 01]], p.2^] The global environmental impact might be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot, which has high global warming potential (GWP).[^Adam Mann, "[[http://www.nature.com/news/2010/101022/full/news.2010.558.html#B1 | "Space tourism to accelerate climate change"]], 22 October 2010, [[http://en.wikipedia.org/wiki/Nature_(journal) | Nature]], doi:10.1038/news.2010.558^],[^Geophysical Research Letters, v.37, 2010, "[[http://www.agu.org/pubs/crossref/2010/2010GL044548.shtml | Potential climate impact of black carbon emitted by rockets]]", Martin Ross, Michael Mills, Darin Toohey, doi:10.1029/2010GL044548^]

%center% http://revolution-green.com/wp-content/uploads/2015/07/news5-1-0f193624dac1f03c.jpg | The [[ram accelerator]] facility at the University of Washington]]

%center% http://revolution-green.com/wp-content/uploads/2015/07/news5-1-0f193624dac1f03c.jpg | [[http://ramaccelerator.org/home/node/7| The ram accelerator facility at the University of Washington]]

%center% http://revolution-green.com/wp-content/uploads/2015/07/news5-1-0f193624dac1f03c.jpg | [[http://www.hypersciences.com/ | Hypersciences]] aims to exploit the ram accelerator for drilling

A more serious objection to projectile space launch from the Earth's surface is environmental: atmospheric shock waves.  The muzzle shock wave from [[light gas gun]] launches at Lawrence Livermore was strong enough to kill nearby plant life. '''(Ref needed)'''  Endangered animal species, such the Andean Condor, might be displaced from some habitats, and significantly disturbed in others.  Sonic booms from the projectile might be very alarming and stressful to people even hundreds of kilometers away.  Careful siting, timing and advance warning might ameliorate the problem to some extent.  With an exit point from a volcano crater, perhaps a significant portion of the shock could be deflected upward; higher launch altitudes would tend to reduce shock intensity; and higher altitudes also correlate with more remote locations, with fewer human and animal inhabitants.  Sonic shock environmental impact is an important criterion for narrowing the choice of sites, and will likely be an ongoing research topic even after likely sites are chosen for preliminary development.

well, firstly, the arcdae replaced the core version, your talking about the xbox 360 pro, the difference is, the arcdae comes as the console, with 256mb memory card, 5 arcdae games on a disc and standard AV cables. The pro version comes with a 60gig HDD and HD/standard AV cables, wired head set and no arcdae games just demos. The Elite comes with a 120gig HDD and HDMI cable, black controller and black wired headset, i also believe the pro has a HDMI port, not too sure about the arcdae though. I would advised getting the elite though, as if you get live, this is better for downloads for games or even movies!!!!ps: if you do get live, my gamer tag is DAZ4518 (this is case sensitive)

Uea6ll  <a href="http://ekdccfbvmvqi.com/">ekdccfbvmvqi</a>

our company is heaedd in the future. Here are a couple of social media tools worth noting:Cacoo: a0Check out the new Google+ hangout Cacoo app toa0wire-frame, mind-map and diagram with

it's 10m/ss the moment it levaes your hand.                                                                                                                  cheese0cake says:                                    i got 1 questionfor example you throw a ball up at 10m/sat t=0, is v=0m/s (snce motion hasn't started yetor v = 10m/ss                                                                                                                  mansur123 says:                                    @achtpanz88 Yes it does.                                                                                                                  leadershipcouncil says:                                    How fast did I throw up? LOLLL                                                                                                                  Exildeutscher says:                                    thats because you have to throw against the pull of gravity. so basically you throw it at x m/s UP, which is your initial velocity, at the half-way mark, the velocity changes to x m/s DOWN, or -x m/s UP. From there on, the velocities start to cancel each other out, leaving you with 0.                                                                                                                  achtpanz88 says:                                    I have a question: In a projectile motion (one motion), does the time for the object to travel from the starting point (y*0=0) to the highest point equal to the time for the object to travel from that highest point to the end y=0?                                                                                                                  hollyflowerrose says:                                    I understand why final velocity is zero, but it always seems to me that initial velocity would also be zero, because the ball has not been thrown yet. What am I missing here?                                                                                                                  RichardJordan100 says:                                    ball throwing                                                                                                                  gklrajan says:                                    gr8! i tried to solve it the other way i.e. by taking vi=0 nd taking vf=unknown nd i got the same answer 35m/s  thankyou! for giving such a gud aproach 2 dis prblm cuz wat v usually do is mug up the formulae nd aplly it but this is really get! after watchin ur videoes i started appretiating phy but nyway its too late nw.. i'm alredy prep 4 medical!! thanks a lot sal!                                                                                                                  RodimusX says:                                    thanks so much for posting all these wonderful videos! they really do help me out a lot. i have always loved physics until this year where i had such a difficult time keeping up. i really wanted to enjoy it again so you are definitely being a real big help. i appreciate it.                                                                                                                    NewMnT says:                                    Your vids r real helpful. Thankx for uploading.                                                                                                                  Evidenced says:                                    He solved the problem without resorting to formulas. Since you knew the t = 3.5 secs and g = -10m/s^2  you know that v_i must be 35 because 35  (1)10  (1)10  (1)10  (1/2)10 = 0. Now that you have v_i and v_f, you just average the two and plug it in d = (v_a)(t). (you can average them simply because the velocity is linear and the acceleration is constant).                                                                                                                  bkjoelover says:                                    why cant we use the distance= (vf2-vi2)/2a?

'''Projectile space launch''' - the use of ground-based accelerators to help put payloads into orbit.

Putting things into orbit is expensive. The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. [^ "Ground-based, hypervelocity accelerators for low-cost delivery of large numbers of small, high-g tolerant payloads to LEO are a near-term technology that can provide significant payoff for a relatively small technology investment." NASA, April 2012. [[http://www.nasa.gov/pdf/500393main_TA01-ID_rev6-NRC-wTASR.pdf | Launch Propulsion Systems Roadmap: Technology Area 01]], p.2^] The global environmental impact might be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot, which has high global warming potential (GWP).[^Adam Mann, "[[http://www.nature.com/news/2010/101022/full/news.2010.558.html#B1 | "Space tourism to accelerate climate change"]], 22 October 2010, [[http://en.wikipedia.org/wiki/Nature_(journal) | Nature]], doi:10.1038/news.2010.558^],[^Geophysical Research Letters, v.37, 2010, "[[http://www.agu.org/pubs/crossref/2010/2010GL044548.shtml | Potential climate impact of black carbon emitted by rockets]]", Martin Ross, Michael Mills, Darin Toohey, doi:10.1029/2010GL044548^]

[[Project Persephone]]'s focus on aid and development projects in [[equatorial alpine regions]] is strongly motivated by the likelihood that these regions can be made ideal for projectile space launch. Of course, such regions also tend to be relatively undeveloped and energy-poor. Space launch tends to require expensive labor ([[recurring engineering costs]]) from developed countries, and it's also quite energy-intensive.  However, some schemes for projectile launch, such as the [[ram accelerator]], could require relatively little energy per unit of mass orbited, and only very simple infrastructure requiring relatively little expert operation and maintenance.

Communities in alpine equatorial regions might be able to provide most of the basic material and energy for launch.  In particular, the [[ram accelerator]] shows promise for providing high accelerations from tubes that, with appropriate engineering[^"Gasdynamic Operation of Baffled Tube Ram Accelerator in Highly Energetic Mixtures", A.J. Higgins, C. Knowlen, C.B. Kiyanda, Submitted to: 20th International Colloquium on the Dynamics of Explosions and Reactive Systems. http://www.galcit.caltech.edu/~jeshep/icders/cd-rom/EXTABS/178_20TH.PDF^] might be made from materials far less exotic than many of those seen in high-performance aerospace applications.  The energy from the byproducts of [[sustainable forestry]], and using off-peak electricity surpluses from [[small hydro]], [[wind power]] and [[geothermal energy]] might be more than adequate. If the crater of a dormant or extinct volcano considered as a launch point contains a caldera lake, the same drilling equipment used for tapping geothermal sources might be used to bore a "pilot tunnel" from the crater to the base, for small hydro. Development of such energy sources in candidate regions for local community use and for supplying their neighboring communities, should take precedence as a Project focus. The Project would help supply the needed equipment and expertise in exchange for promises of an adequate share of energy, if and when the time comes for projectile launch development.

There has been research, even relatively recently, on boosting partly air-breathing spacecraft up to supersonic speeds along more-or-less horizontal tracks, with a view toward eventually hosting man-rated launchers[^"First Stage of a Highly Reliable Reusable Launch System", Kurt J. Kloesel, Jonathan B. Pickrel, Emily L. Sayles, Michael Wright, Darin Marriott, Leo Holland, Stephen Kuznetsov, AIAA 2009-6805. http://pdf.aiaa.org/preview/CDReadyMSPACE09_2074/PV2009_6805.pdf^].  However, Project Persephone doesn't aim for manned launch, which is inevitably expensive.  Instead of relatively low horizontal acceleration as a prelude to hypersonic aerodynamic stages, it looks instead to sites for high-angle, very high acceleration launch from mountain slopes, particularly those of extinct or dormant stratovolcanoes near the equator, obviating the need for complex air-breathing propulsion stages.

A common objection to projectile space launch is that nothing of any complexity could survive it -- at best, it's thought that only bulk materials might be shipped.  However, complex unpiloted aerial vehicles have been designed that fold into a package formed as a standard 155 mm artillery round, demonstrating in tests that they can function after being subjected to 12,000 g accelerations.[^"Flyer Assembly", Patent No 6,392,213 B1 Issued May 21, 2002 http://www.draper.com/digest03/patent103.pdf^] The payloads required for [[telebots | telebotic]] construction of [[exovivaria]] can almost certainly be engineered to survive similar launch stresses, if necessary.

Another common objection to projectile space launch is that the vehicles would simply disintegrate in the lower atmosphere.  However, it's been estimated that even low-mass projectiles exiting an accelerator at sea level could survive transit of the atmosphere with less than half of their mass devoted to cooling or ablative shielding.[^http://www.cs.cmu.edu/afs/cs/usr/mnr/st/std027, http://www.tbfg.org/papers/Ram%20Accelerator%20Technical%20Risks%20ISDC07.pdf^].  For larger projectiles at higher altitudes, the mass requirement for thermal protection has been estimated as low as 1% of total mass accelerated.

A more serious objection to projectile space launch from the Earth's surface is environmental: atmospheric shock waves.  The muzzle shock wave from [[light gas gun]] launches at Lawrence Livermore was strong enough to kill nearby plant life. '''(Ref needed)'''  Endangered animal species, such the Andean Condor, might be displaced from some habitats, and significantly disturbed in others.  Sonic booms from the projectile might be very alarming and stressful to people even hundreds of kilometers away.  Careful siting, timing and advance warning might ameliorate the problem to some extent.  With an exit point from a volcano crater, perhaps a significant portion of the shock could be deflected upward; higher launch altitudes would tend to reduce shock intensity; and higher altitudes also correlate with more remote locations, with fewer human and animal inhabitants.  Sonic shock environmental impact is an important criterion for narrowing the choice of sites, and will likely be an ongoing research topic even after likely sites are chosen for preliminary development.

!! References

* The Space Review, "Space and (or versus) the environment", http://thespacereview.com/article/1395/1

[^#^]

Putting things into orbit is expensive. The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. The global environmental impact might be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot, which has high global warming potential (GWP).[^Adam Mann, "[[http://www.nature.com/news/2010/101022/full/news.2010.558.html#B1 | "Space tourism to accelerate climate change"]], 22 October 2010, [[http://en.wikipedia.org/wiki/Nature_(journal) | Nature]], doi:10.1038/news.2010.558^],[^Geophysical Research Letters, v.37, 2010, "[[http://www.agu.org/pubs/crossref/2010/2010GL044548.shtml | Potential climate impact of black carbon emitted by rockets]]", Martin Ross, Michael Mills, Darin Toohey, doi:10.1029/2010GL044548^]

Putting things into orbit is expensive. The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. The global environmental impact might be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot, which has high global warming potential (GWP).[^Adam Mann, "[[http://www.nature.com/news/2010/101022/full/news.2010.558.html#B1 | "Space tourism to accelerate climate change"]], 22 October 2010, [[http://en.wikipedia.org/wiki/Nature_(journal) | Nature]], doi:10.1038/news.2010.558^][^Geophysical Research Letters, v.37, 2010, "[[http://www.agu.org/pubs/crossref/2010/2010GL044548.shtml | Potential climate impact of black carbon emitted by rockets]]", Martin Ross, Michael Mills, Darin Toohey, doi:10.1029/2010GL044548^]

Putting things into orbit is expensive. The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. The global environmental impact might be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, it should be possible to launch lots of cargo into orbit with much less degradation of the atmosphere by pollutants such as soot, which has high global warming potential (GWP).[^"[[Space tourism will accelerate climate change, warn scientists as Sir Richard Branson unveils world's first commercial spaceport | http://www.dailymail.co.uk/sciencetech/article-1323494/Sir-Richard-Branson-unveils-worlds-commercial-spaceport.html]], Daily Mail, 25 October 2010^]

[^#^]

Putting things into orbit is expensive. The recurring engineering costs required to orbit payloads using projectile space launchers should be far lower than those for rocketry, perhaps by an order of magnitude. The overall environmental impact might be lower as well. For example, by avoiding or minimizing rocket firings in the atmosphere, degradation of the ozone layer by exhaust pollutants can be avoided.

The [[recurring engineering costs]] for putting a given mass into orbit with projectile space launch should be far lower than those for rocketry, perhaps by an order of magnitude.  The overall environmental impact might be lower as well.  For example, by avoiding or minimizing rocket firings in the atmosphere, degradation of the ozone layer by exhaust pollutants can be avoided.

[[Project Persephone]]'s focus on aid and development projects specifically in [[equatorial alpine regions]] is strongly motivated by the likelihood that these regions can be made ideal for projectile space launch.  Of course, such regions also tend to be relatively undeveloped and energy-poor.  Space launch tends to require expensive labor ([[recurring engineering costs]]) from developed countries, and it's also quite energy-intensive.  However, some schemes for projectile launch, such as the [[ram accelerator]], could require relatively little energy per unit of mass orbited, and only very simple infrastructure requiring relatively little expert operation and maintenance.

Communities in alpine equatorial regions might be able to provide most of the basic material and energy for launch.  In particular, the [[ram accelerator]] shows promise for providing high accelerations from tubes that, with appropriate engineering[^"Gasdynamic Operation of Baffled Tube Ram Accelerator in Highly Energetic Mixtures", A.J. Higgins, C. Knowlen, C.B. Kiyanda, Submitted to: 20th International Colloquium on the Dynamics of Explosions and Reactive Systems. http://www.galcit.caltech.edu/~jeshep/icders/cd-rom/EXTABS/178_20TH.PDF^] might be made from materials far less exotic than many of those seen in high-performance aerospace applications.  The energy from the byproducts of [[sustainable forestry]], and using off-peak electricity surpluses from [[small hydro]], [[wind power]] and [[geothermal energy]] might be more than adequate. If the crater of a dormant or extinct volcano considered as a launch point contains a caldera lake, the same drilling equipment used for tapping geothermal sources might be used to bore a "pilot tunnel" from the crater to the base, for small hydro. Development of such energy sources in candidate regions for local community use and for supplying neighboring communities in candidate regions, should take precedence as a Project focus, with the Project supplying equipment and expertise in exchange for promises of an adequate share of energy. 

Communities in alpine equatorial regions might be able to provide most of the basic material and energy for launch.  In particular, the [[ram accelerator]] shows promise for providing high accelerations from tubes that, with appropriate engineering[^"Gasdynamic Operation of Baffled Tube Ram Accelerator in Highly Energetic Mixtures", A.J. Higgins, C. Knowlen, C.B. Kiyanda, Submitted to: 20th International Colloquium on the Dynamics of Explosions and Reactive Systems. http://www.galcit.caltech.edu/~jeshep/icders/cd-rom/EXTABS/178_20TH.PDF^] might be made from materials far less exotic than many of those seen in high-performance aerospace applications.  The energy from the byproducts of [[sustainable forestry]], and using off-peak electricity surpluses from [[small hydro]], [[wind power]] and [[geothermal energy]] might be more than adequate.  Development of such energy sources in candidate regions, for local community use, and for supplying neighboring communities in candidate regions, should take precedence as a Project focus.