Einstien was theorizing based on experimental results including the Michelson-Morley experiment on the invariance of the speed of light and on the observed precession of thje orbit of Mercury. These observations were at odds with classical physics but were explained by Special and General Relativity respectively.
What has also changed is the destruction of natures ability to recover from human insults. Our insults are orders of magnitude larger due to both population and technology and the remaining natural environment has shrunk due to our approriation and conversion of wetlands, estuaries and flood plains.
The 100 mile lower limit in my example was selected as an estimate of a point where drag was neglible. If not, change it to a point where it is effectively zero. Remember that the path of the endpoint is essentially straight down to 100 miles and then straight up.
The forces in my 1000 mile example are much less than they would be in the 55,000 mile full space elevator. The point is that the length would be driven by the available materials.
One weakness of the plan, as I see it, is the all or nothing nature of the plan. A less risky plan that could be a stepping stone to a space elevator is to start with a much smaller rotating tether in orbit.
Imagine a thousand mile long tether in orbit with its center of gravity 600 above the earths surface. In addition to orbiting the earth The tether would rotate about its center of gravity at a rotation speed such that its speed relative to the earths surface at its ends closent approch would be zero.
A rocket would have to ascend to 100 miles up and rondezvous with a a tether end that, for the moment, is stationary. It would remain atteached to the tether while the tether rotated 180 degrees about its center of gravity. At tht point the rocket would be 1100 miles above the earth and traveling at about twice orbital velocity. If the rocket detatched at this point would would be well above escape velocity.
Longer tethers would reduce G forces and avoid the need for the first 100 mile step. The ultime version of the tether would have a CG in geosynchronous orbit and aon end on the ground.
Carnegie Mellon University West at Sunnyvale CA has such a one semester course as part of its Masters Program. A description follows:
Managing Outsourced Development (MOD) Certificate consists of three separate tasks:
Task 1 - Project Initiation and Planning: Perform project initiation and planning by building a Project Charter, Project Plan, Procurement and Solicitation Plan, and a presentation to management that recommends the viability of the project, including the team's recommendation and rationale for outsourcing. The primary focus is on utilizing project management techniques to define the project and determine how it will be managed. In addition to building a complete project plan, the students will also build a procurement and solicitation plan. Students will present their recommendations to management to request budget and get the approval to move forward.
Task 2 - Risk Management and Solicitation: Enact your risk management process, from Task 1, by identifying, analyzing, and mitigating risks associated with the project. Perform the next step in solicitation planning by detailing out how solicitation will be performed and a vendor will be selected utilizing techniques that reduce risk. This effort includes developing the evaluation criteria for vendor selection and drafting the documents necessary for the solicitation package. The final piece is to write up your contract type recommendation that includes the benefits and drawbacks of at least three types of contracts.
Task 3 - Project Execution and Closeout: Perform project execution and close-out in a simulated environment. You will be provided with information associated with post contract award to start the simulation. Each student will be presented with a series of communications, that you need to analyze and develop action plans as well as communications in response. At the end of each scenario, after your individual response, you are to gather as a team and compile the "best of the best" results in a team response to the scenario. At this point you will also be asked to answer specific questions associated with the scenario. As you progress through the simulation, you are also expected to perform aspects of your project plan regarding monitoring and control and upload that information to your team site. The last scenario is for you to perform the project and contract close-out process as a team.
Slashdot Mirror
Einstien was theorizing based on experimental results including the Michelson-Morley experiment on the invariance of the speed of light and on the observed precession of thje orbit of Mercury. These observations were at odds with classical physics but were explained by Special and General Relativity respectively.
How about:
Religion is a con game.
Faith is gullibility.
I believe in evidence and logic.
What has also changed is the destruction of natures ability to recover from human insults. Our insults are orders of magnitude larger due to both population and technology and the remaining natural environment has shrunk due to our approriation and conversion of wetlands, estuaries and flood plains.
The 100 mile lower limit in my example was selected as an estimate of a point where drag was neglible. If not, change it to a point where it is effectively zero. Remember that the path of the endpoint is essentially straight down to 100 miles and then straight up.
The forces in my 1000 mile example are much less than they would be in the 55,000 mile full space elevator. The point is that the length would be driven by the available materials.
One weakness of the plan, as I see it, is the all or nothing nature of the plan. A less risky plan that could be a stepping stone to a space elevator is to start with a much smaller rotating tether in orbit.
Imagine a thousand mile long tether in orbit with its center of gravity 600 above the earths surface. In addition to orbiting the earth The tether would rotate about its center of gravity at a rotation speed such that its speed relative to the earths surface at its ends closent approch would be zero.
A rocket would have to ascend to 100 miles up and rondezvous with a a tether end that, for the moment, is stationary. It would remain atteached to the tether while the tether rotated 180 degrees about its center of gravity. At tht point the rocket would be 1100 miles above the earth and traveling at about twice orbital velocity. If the rocket detatched at this point would would be well above escape velocity.
Longer tethers would reduce G forces and avoid the need for the first 100 mile step. The ultime version of the tether would have a CG in geosynchronous orbit and aon end on the ground.
Carnegie Mellon University West at Sunnyvale CA has such a one semester course as part of its Masters Program. A description follows:
Managing Outsourced Development (MOD) Certificate consists of three separate tasks:
Task 1 - Project Initiation and Planning:
Perform project initiation and planning by building a Project Charter, Project Plan, Procurement and Solicitation Plan, and a presentation to management that recommends the viability of the project, including the team's recommendation and rationale for outsourcing. The primary focus is on utilizing project management techniques to define the project and determine how it will be managed. In addition to building a complete project plan, the students will also build a procurement and solicitation plan. Students will present their recommendations to management to request budget and get the approval to move forward.
Task 2 - Risk Management and Solicitation:
Enact your risk management process, from Task 1, by identifying, analyzing, and mitigating risks associated with the project. Perform the next step in solicitation planning by detailing out how solicitation will be performed and a vendor will be selected utilizing techniques that reduce risk. This effort includes developing the evaluation criteria for vendor selection and drafting the documents necessary for the solicitation package. The final piece is to write up your contract type recommendation that includes the benefits and drawbacks of at least three types of contracts.
Task 3 - Project Execution and Closeout:
Perform project execution and close-out in a simulated environment. You will be provided with information associated with post contract award to start the simulation. Each student will be presented with a series of communications, that you need to analyze and develop action plans as well as communications in response. At the end of each scenario, after your individual response, you are to gather as a team and compile the "best of the best" results in a team response to the scenario. At this point you will also be asked to answer specific questions associated with the scenario. As you progress through the simulation, you are also expected to perform aspects of your project plan regarding monitoring and control and upload that information to your team site. The last scenario is for you to perform the project and contract close-out process as a team.