Starship Asterisk*

THX1138 wrote:None the less I personally agree that our present mode of transportation, for lack of a more fitting word “sucks “ Dragging our feet from moon to planets and or etc at a whopping 25,000 mph is not going to cut it boys. Maybe in 10 or 20 years someone will have perfected any one of a number of different propulsion techniques that are currently being envisioned, I certainly hope so.

http://www.youtube.com/watch?v=36lJMpzbOA4 wrote:And you can fly high as a kite if you want to
Faster than light if you want to
Speeding through the universe
Thinking is the best way to travel

It's all a dream, light passing by on a screen
And there's you and I on a beam
We ride the waves
Distance is gone, will we find out?
How life began, will we find out?
Speeding through the universe
Thinking is the best way to travel

BMAONE23 wrote:There is one good thing to be gained from a permanent presence on the moon...a Launch base that enters space at vastly greater speeds that could be gained by leaving a gravity well 1/6th that of Earth (unfortunately, everything needed would likely require boosting out of Earth's gravity well first before lunar assembly could occur)

http://en.wikipedia.org/wiki/Mass_driver wrote:
<<A mass driver or electromagnetic catapult is a proposed method of non-rocket spacelaunch that would use a linear motor to accelerate and catapult payloads up to high speeds. All existing and contemplated mass drivers use coils of wire energized by electricity to make electromagnets. Sequential firing of a row of electromagnets accelerates the payload along a path. After leaving the path, the payload continues to move due to inertia.

A mass driver is essentially a coilgun that magnetically accelerates a package consisting of a magnetisable holder containing a payload. Once the payload has been accelerated, the two separate, and the holder is slowed and recycled for another payload.

Mass drivers can be used to propel spacecraft in two different ways: A large, ground-based mass driver could be used to launch spacecraft away from the Earth or another planet. A spacecraft could have a mass driver on board, flinging large pieces of material into space to propel itself. A hybrid design is also possible (see coilgun, railgun, or helical railgun).

Generally speaking, mass drivers are practical for small objects at a few kilometers per second; for example 1 kg at 2.5km/s. Heavier objects go proportionally more slowly; and lighter objects may be projected at 20km/s or more. The limits are generally the cost of the silicon to switch the current and the cost of the power supply and temporary energy storage for it. However, energy can be stored inductively in superconducting coils. A 1 km long mass driver made of superconducting coils can accelerate a 20kg vehicle to 10.5 km/s at a conversion efficiency of 80%, and average acceleration of 5,600 gee. Even so, Earth-based Mass drivers for propelling one-tonne vehicles to orbit are unlikely to be cost effective in the near future.

The Earth's strong gravity and thick atmosphere make such an installation difficult, so many proposals have been put forward to install mass drivers on the moon where the lower gravity and lack of atmosphere significantly reduce the required velocity to reach lunar orbit.

Most serious mass driver designs use superconducting coils to achieve reasonable energetic efficiency (approximately 50%). The best known performance occurs with an aluminum coil as the payload. The coils of the mass-driver induce eddy-currents in the payload's coil, and then act on the resulting magnetic field. There are two sections of a mass-driver. The maximum acceleration part spaces the coils at constant distances, and synchronize the coil currents to the bucket. In this section, the acceleration increases as the velocity increases, up to the maximum that the bucket can take. After that, the constant acceleration region begins. This region spaces the coils at increasing distances to give a fixed amount of velocity increase per unit of time.

In this mode, the major proposal for use of mass-drivers was to transport lunar surface material to space habitats so that it could be processed using solar energy. The Space Studies Institute showed that this application was reasonably practical. In the prototypes, the payload would be held in a bucket and then released, so that the bucket can be decelerated and reused. A disposable bucket, on the other hand, would avail acceleration along the whole track.>>

THX1138 wrote:BMAONE23
How much more velocity “ round about “ would a moon based launch be able to attain?
The whole less gravity thing never occurred to me “ and sadly, no surprise there “ But are we talking like double or more of what we are doing now?
17,500 = 35,000 or ?