You're talking about something that is compact and has a mass of between a few grams and a few tens of kilograms.
The article is about a 2 tonne spacecraft attached to a tether, which is anchored by a harpoon, and the article talks about braking forces of less than 5G.
A 500km long carbon nanotube rope (3600MPa Ultimate Tensile Strength) strained to 75% breaking strength (2700MPa) and handling a force of 200 kilonewtons (2 tonnes times 10G) would need to have a cross-sectional area of about 70mm^2, and would have a mass of about 50kg.
It'd need either a pretty long tether - at a minimum 500km assuming a 10G acceleration and 10km/s initial relative velocity, or 5000km for a more sedate 1G acceleration.
The italic cursive shown in that article is already taught in Queensland primary schools - in fact, it was taught 20 years ago when I was in primary school.
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OK - my maths was out by 3 orders of magnitude. A 500km long 70mm^2 Carbon nanotube rope would have a mass of about 50 tonnes, not 50kg.
Even with 3.6GPa ultimate tensile strength (2.75x10^6 N.m/kg specific strength) of carbon nanotube ropes, it won't work.
Assuming a 2 tonne craft (as specified in the article), assuming 100% loading:
Required specific strength, assuming a rope with a mass of 2 tonnes, giving a total mass of 4 tonnes: (10^6m x 2x10^5N) / 2x10^3kg = 1x10^8 N.m/kg
You're talking about something that is compact and has a mass of between a few grams and a few tens of kilograms.
The article is about a 2 tonne spacecraft attached to a tether, which is anchored by a harpoon, and the article talks about braking forces of less than 5G.
A 500km long carbon nanotube rope (3600MPa Ultimate Tensile Strength) strained to 75% breaking strength (2700MPa) and handling a force of 200 kilonewtons (2 tonnes times 10G) would need to have a cross-sectional area of about 70mm^2, and would have a mass of about 50kg.
It'd need either a pretty long tether - at a minimum 500km assuming a 10G acceleration and 10km/s initial relative velocity, or 5000km for a more sedate 1G acceleration.
The italic cursive shown in that article is already taught in Queensland primary schools - in fact, it was taught 20 years ago when I was in primary school.