Astronomy/cosmology questions...

[Buster's Uncle]

I wanna talk about orbital tether power and braking, too...

[Geo]

I wanna talk about orbital tether power and braking, too...

From what I read about it, its... flimsy...

[Buster's Uncle]

The only experiment I'm aware of, as discussed previously, melted/broke the tether in a hurry - but that's surely a straightforward engineering problem, probably solved with a simple thicker wire?

Of COURSE they used a flimsy wire - boosting mass costs.

[Metaliturtle]

The only experiment I'm aware of, as discussed previously, melted/broke the tether in a hurry - but that's surely a straightforward engineering problem, probably solved with a simple thicker wire?

Of COURSE they used a flimsy wire - boosting mass costs.

Is there a material that can withstand that amount of rotation? even if it's thick? That material science could make enough of?

[Buster's Uncle]

No rotation need apply - a tidal effect stretches the wire out into higher -and/or lower- orbit, the force pretty slight absent MILES and miles of wire, and passing a wire through a magnetic field -Earth's- generates current, it turns out, a LOT of juice, enough to melt a flimsy wire...

[Geo]

Of COURSE they used a flimsy wire - boosting mass costs.

I was reminded of that when talking to an engineer who works for (one of) the companies that constructed the PROBA3 probe.
Its a twin satellite setup where one probe creates an artificial eclipse of the sun for one flying in formation with it (to observe the corona). Both probes use a propulsion system to align themselves at the apogee part of their orbit.
One of my questions to this speaker was if during the design phase there had been talk about using tethers to keep those probes in permanent alignment, and he told me that wasn't on the table. A bit later I learned there's only 24-25 kg propellant in one probe, and a mere 12 kg in the other one, so it makes sense tethers weren't used in that setup. Those would probably have massed more then the propellant mass plus tank combined. I'm used to thinking of a probe having hundreds of kilo's of propellant onboard, not a mere couple dozen.

[Buster's Uncle]

They could have stayed away from metal for the tethers -maybe- but that tends to get into a bulk tradeoff if it even works, which isn't as inherent an expense, but can be very problematic depending on available space considerations.