On Sun, Feb 25, 2018 at 10:10 PM, Tim <xxxxxx@little-possums.net> wrote:

. . . shooting straight for them at about 100 miles per hour.

So, about the speed of a bullet train . . .

If the payload isn't right there, at the right place and time to latch on . . .

A straight and level stretch of track, a governed speed of 100 mph, a big hook and an even bigger V-shaped hook funnel (like on the front of planes used for Fulton extractions) . . .

. . . current tether materials can't support the 7+ km/s rotation required for a stationary pickup.

According to wikipedia (admittedly not the best source), we're about halfway there (3.5 km/s with off-the-shelf materials), although I noted an admission that the pick-up end of the tether would be subject to significant erosion due to friction heating (e.g. would need to be replaced often).

Still, I believe the OP was willing to assume working hot fusion as a common technology, so I think 7+ km/s not unattainable in his TU.

Richard Aiken

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