Space-elevator tether climbs a mile high

Actually that has been addressed, several times. In fact, look up thread just a few posts and you find a few.

That all depends on how fast you lift it, how tight the cable is, and the mass of the assembly.

Did some more reading. It seems my assumption about the cable being held in tension by a weight at above geosynchronous orbit was correct.

Never mind all the questions then as they're irrelevant in that type of setup.

Thanks anyway.

You're right. You did mention it in your posts #s 184 & 187.

The horizontal force you mention is refered to as what's needed to counteract "coriolis" acceleration.

And I was wrong about the counterweight out at 62,000 miles being at a horizontal velocity of 41,000 miles per hour. My brand new calculator tells me that the actual horizontal velocity of the distant counterweight is on the order of 18,000 mph.

So if the tether ever separated, the counterweight would not fly off into space, never to return, but would, instead, loop up in a tremendous eliptical path and pay a splashing visit to the earth a little later, with whatever "tail" was still attached to it following.

Correct.

And any payload lifted to that height and released would still need rocket assist to achieve escape velocity. Also, any payload attached to the ribbon between 22,000 miles (geosynchronous orbit) and 62,000 miles will be adding to the tension on the Earth anchor.

In space, the anchor would be a geo-stationary orbiting counterweight. You cannot do that above the pole.

The tether point is very secure and can be and will be protected by some of the most lethal and capable laser defense systems, firing lasers at the speed of light to disable any attacking force in seconds once identified and acquired...ZAP...Zot...end of Plot!!!

The lift cables are very straight in geosynchronous orbit, like a spoke on a wheel...this nano carbon fiber cable system, is so strong approaching 100 giga pascals...( that is 100 plus times greater strength than steel) and this carbon fiber is the only material known on earth strong enough to take the centrifugal forces that keep the whole thing attached to the Port connection here on earth...this will be a remarkable achievement... I want on the first commercial lift!!!

A few more points about the elevator concept-

-The cable is in tension, but the center of mass must be at the geosync alittude. Below geosync, gravity > centripetal acceleration, and the cable will be pulled tight to earth. Outside the geosync orbit, the rotation will cause the cable to be tensioned away from earth. If the overall center of gravity of the system shifts (much) from geosync, the entire structure will begin to wrap around the earth (Eastbound if it loses altitude, west if it gains).

-Payloads released fron the geosync point outwards would be accelerated beyond orbital velocity by the rotation, and would achieve an inexpensive interplanetary boost. Payloads (or counterweights) moving on the outer portion of the cable could be used to counterbalance payloads lifted from earth.

-It is correct that the flex in this system will add some incredibly complex dynamics, and I've simplified/ignored that for the most part here. The dynamics of the system are strictly a function of weight, position, and velocities, and are solvable. The control system (managing both the movement of payload, counterweights, and a large array of small control jets) would be just as large an accomplishment as the material breakthrough of building the cable, in my mind. Extremely difficult, but not impossible.

another space tether:

http://spaceflightnow.com/news/n0709/15foton/

Recoverable craft shot into space for science mission
BY STEPHEN CLARK
SPACEFLIGHT NOW
Posted: September 15, 2007

Russia launched a recoverable capsule crammed with more than 1,300 pounds of international scientific and engineering test experiments on Friday to begin a 12-day excursion in space.

The Foton M3 capsule, loaded with an array of Russian and European payloads, was launched at 1100 GMT (7:00 a.m. EDT) aboard a Soyuz rocket from the Baikonur Cosmodrome in Kazakhstan.

A carrier called FLOYD on the Foton capsule will unreel nearly 19 miles of tether material in the early morning hours Sept. 25. A 12-pound craft called Fotino and a disposable instrumentation box known as MASS will be attached to the end of the tether, which is as thin as a typical fishing line.

Fotino will fly ahead and below the Foton spacecraft during much the automated two-and-a-half hour activation and deployment process. At the time of Fotino’s release, the capsule will be in a gravity-induced backward swing relative to Foton, according to Michiel Kruijff, technical director for Delta-Utec and lead engineer for the YES2 mission.

Fotino will become the smallest spacecraft to re-enter Earth’s atmosphere, and the nearly 20-mile length of the tether will make it the longest ever flown in space.

Tethered delivery systems could provide opportunities for inexpensive return options for small payloads in orbit. Engineers have considered using such systems to return equipment from the international space station, but Kruijff said safety issues will likely thwart those concepts.