Feasibility study of a mission to Sedna – Nuclear propulsion and solar sailing

Sedna's perihelion is ~76 AU - more than twice as far as Pluto, which took New Horizons nearly a decade to reach.

Sedna's apehelion is over 500 AU.

> The Direct Fusion Drive rocket engine is under development at Princeton University Plasma Physics Laboratory

Is it ... is it actually working? How close are they? And even if they get it to work next year, will it be something well-engineered & reliable enough to send it into space for 10 years and expect it to work?

> Modelling shows that this technology can potentially propel a spacecraft with a mass of about 1,000 kg (2,200 lb) to Pluto in 4 years.

They're apparently targeting an in-orbit test in 2027. Even if this were to slip to 2030, and becomes commercially available in 2040, I expect that would be plenty of time for a rendezvous with Sedna's perihelion

Hopefully this time round it goes a bit better than that.

My hope with Pulsar Fusion is that their existing thruster business provides the necessary revenue to both keep them solvent, and attract continued investment, until they're able to get their Fusion Drive off the ground.

It was bad enough that Richard Branson discredited private orbital spaceflight with the overly long development process for a vehicle that made the Space Shuttle look like a paragon of safety and low costs -- Skylon was so much worse.

https://www.newscientist.com/blogs/shortsharpscience/2009/03...

'Trying to build a spaceship by making aeroplane fly faster and higher is like trying to build an aeroplane by making locomotives faster and lighter - with a lot of effort, perhaps you could get something that more or less works, but it really isn't the right way to proceed. The problems are fundamentally different, and so are the best solutions.

As Mitch Burnside Clapp, former US Air Force test pilot and designer of innovative launcher concepts, once commented: "Air breathing is a privilege that should be reserved for the crew".'

(The original link says "Page is Gone")

And here's some more quoting

Could a single-stage-to-orbit spaceship, something that could operate rather like an aeroplane, be built with just rocket engines? Well, actually, yes. In the 1980s, NASA and the US Air Force spent about $2 billion trying to build the X-30, a single-stage spaceship powered by scramjets (with help from rockets, of course). It never flew. At the same time, for comparison, NASA's Langley Research Center studied building a single-stage pure-rocket spaceship. The results were interesting.

The pure-rocket design was more than twice as heavy as X-30 at takeoff, because of all that LOX. On the other hand, its empty weight - the part you have to build and maintain - was 40% less than X-30's. It was about half the size. Its fuel and oxidiser together cost less than half as much per flight as X-30's fuel. And finally, because it quickly climbed out of the atmosphere and did its accelerating in vacuum, it had to endure rather lower stresses and less than 1% of X-30's friction heating. Which approach would be easier and cheaper to operate was pretty obvious.

The Langley group's conclusion: if you want a spaceship that operates like an aeroplane, power it with rockets and only rockets.