Posted on 10/19/2020 11:02:50 PM PDT by BenLurkin
Fusion power is the technology that is 30 years away, and always will be, according to skeptics, at least.
Despite its difficult transition into a reliable power source, the nuclear reactions that power the sun have a wide variety of uses in other fields.
The concept fusion drive, called a direct fusion drive (or DFD), is in development at the Princeton Plasma Physics Laboratory (PPPL).
Though still under development, the engine itself exploits many of the advantages of aneutronic fusion, most notably an extremely high power-to-weight ratio. The fuel for a DFD drive can vary slightly in mass and contains deuterium and a helium-3 isotope. Even with relatively small amounts of extremely powerful fuel, the DFD can outperform the chemical or electric propulsion methods that are commonly used today.
The specific impulse of the system, which is a measure of how effectively an engine uses fuel, is estimated to be comparable to electrical engines, the most efficient currently available. In addition, the DFD engine would provide 4-5 N of thrust in low power mode, only slightly less than what a chemical rocket would output over long periods of time. Essentially, the DFD takes the excellent specific impulse of electric propulsion systems and combines it with the excellent thrust of chemical rockets, for a combination that melds the best of both flight systems.
Most outer solar system missions rely on radioisotope thermal generators (RTGs) for their power source. But a DFD is, in fact, a power source in addition to being a source of thrust. If designed correctly, it could provide all the power a spacecraft needs for an extended mission lifespan.
(Excerpt) Read more at phys.org ...
A billion miles away.
That’s at least 300 bucks worth of gas.
Will Slim Pickens be riding it?
1.85 billion miles round trip in 2 years.
That works out to 105,000 mph.
What happens when a space craft hits a tiny space pebble at 105,000 mph?
Depending on the speed and direction of the pebble, I am thinking the kinetic energy would blast a hole right through the space craft.
Use 8 of them and get there in 3 months?
Warp drive will get you there in seconds :)
Spacecraft, Earth, Moon?
Pretty much the same thing that happens when a tiny space pebble strikes the spacecraft at 35,000 mph.
Hint: That scene in "The Empire Strikes Back," when the Millennium Falcon attempts to escape the Empire by deliberately manoeuvering into an asteroid field, grossly exaggerates (by a factor of roughly 100 trillion) what a stable* asteroid field looks like.
Regards,
*"Stable" = won't decay / self-destruct / re-coalesce within 10,000 years (a miniscule time-frame on the cosmic scale).
You would need a deflector shield like the Enterprise .
The Three-Body Problem pertains to three bodies - all of which have appreciable mass (i.e., enough mass to gravitationally affect the other two bodies). Not even the International Space Station (weighing in at 420 metric tons) is anywhere close to massive enough to have any non-negligible effect upon either the Earth or the Moon.
Regards,
Where do you put the beryllium sphere?
Love, Fred Kwan
Nice .. DFD would be cool as a rocket engine!!
i hear there’s a big tom cat on titan... (red dwarf fans know what i’m talking about)
Exactly alexander! Your comment is great. Furthermore for the forum:
It is roughly a doubly restricted 3 body problem.
mass of Saturn >> mass of moon >> mass of spacecraft
But it isnt that either. You have the sun and the other moons and avoiding the rings to consider if you are taking second or third order influences into account.
These things are done numerically.
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