by neufer » Fri Jun 02, 2017 2:45 pm
Case wrote:Boomer12k wrote:
So.... can we "surf" to Alpha Centauri on one?
Math homework problem: how close does a black hole merger have to be, to create a wave strong enough that a space ship from Earth can ride it to the next star? As the wave is directional, how much steering is possible? How do we get off the wave at our destination?
The best emitter of gravitational waves is a close circularly orbiting binary pair of neutron stars or black holes.
Likewise, the best absorber of such gravitational waves is a
matching identical adjacent close circular orbiting binary pair of neutron stars or black holes.
(Note, however, that a close
elliptically orbiting mismatched binary pair of neutron stars or black holes can
self propel itself.)
Even in such extreme cases the reaction motions are no where near relativistic.
Light sails take maximal advantage (i.e., almost total reflection) of the free massless particles impinging on them
but are extremely inefficient in making use of the energies involved (i.e., momentum impulse = 2E/c). Gravitational wave sails take minimal advantage (i.e., almost total transparency) of the free massless particles impinging on them and
they are equally inefficient in making use of the energies involved (i.e., momentum impulse = E/c).
[quote="Case"][quote="Boomer12k"]
So.... can we "surf" to Alpha Centauri on one?[/quote]
Math homework problem: how close does a black hole merger have to be, to create a wave strong enough that a space ship from Earth can ride it to the next star? As the wave is directional, how much steering is possible? How do we get off the wave at our destination?[/quote]
The best emitter of gravitational waves is a close circularly orbiting binary pair of neutron stars or black holes.
Likewise, the best absorber of such gravitational waves is a [b][u]matching identical adjacent[/u][/b] close circular orbiting binary pair of neutron stars or black holes.
(Note, however, that a close [b][u]elliptically orbiting mismatched[/u][/b] binary pair of neutron stars or black holes can [b][u]self propel itself[/u][/b].)
Even in such extreme cases the reaction motions are no where near relativistic.
Light sails take maximal advantage (i.e., almost total reflection) of the free massless particles impinging on them [b][u]but are extremely inefficient in making use of the energies involved (i.e., momentum impulse = 2E/c)[/u][/b]. Gravitational wave sails take minimal advantage (i.e., almost total transparency) of the free massless particles impinging on them and [b][u]they are equally inefficient in making use of the energies involved (i.e., momentum impulse = E/c)[/u][/b].