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> That's mostly guessing, though, as I'm not a rocket scientist and can't find hard information on this.

Yeah, my understanding is that you're wrong on this, though I too am not a rocket scientist. But a few points:

> SpaceX has launched and landed about 10 of these rockets, and has so far reused one. That rocket was first used about a year ago.

While this is factually correct, extrapolating from this will not give any useful insight.

> the amount of effort needed to prepare a rocket for reuse relative to that needed to produce a new rocket

It may be somewhat counter-intuitive, but an already-flown rocket is easier to fly a second time than it is the first time: it's already been "flight-proven." For example, a lot of defects on a microscopic scale simply cannot be detected ahead of time, and the only way to truly detect them is to test the rocket. This is why there are static fires ahead of launch. And it is also why there is a lot of over-engineering (in many things, not just rockets, but airplanes etc.)

The important thing here is that they land the rocket without too many additional stresses. It's not like the Space Shuttle boosters which were dumped into the ocean and had to deal with a lot of refurbishment.

> if they were, I think they would have launched a used rocket earlier.

The first one will always take longer. They're also finalizing the design, and had an accident investigation last year that was a big burden.

> I understand the enthusiasm, but

I'm not sure you do, but I hope I may have convinced you otherwise ;) The answers to your questions could really be "close to 100%" and "a few weeks to months" (more optimistic people will say "days or hours" to that last question).

What they've managed today is a huge milestone, and they're iterating on an astonishing timeframe. They hadn't even landed a single rocket a few years ago, and that was the truly difficult part. It's incredible how fast their progress has been, especially in the context of the space industry generally.

> especially in the context of the space industry generally.

You mean the industry that landed a man on the moon inside of ten years?

Bear in mind their launch manifest, right up until yesterday, assumed that no cores would be re-used and so they had a full slate of flights booked with customers guaranteed first-flight hardware, which they already had in production. They couldn't completely restructure their manufacturing and launch schedule just because they had landed a few cores, some of which we know have been damaged too much to be safely re-used.

Now they have proved the principle of booster re-use they can adjust their manufacturing and launch schedules to take advantage of that going forward.

If I were a SpaceX investor or customer I'd want the manufacturing pipeline and launch schedules to be based as much as possible on facts, not hopes. But now that core re-use is a demonstrated fact, they can be adjusted accordingly without posing unacceptable business risk.

>They will have been extra cautious this time, but from the above, the answers _could_ be "about 10%" and "almost one year, taking way more effort than building a new one does".

not sure if 1 year is actually correct. From what i've read SpaceX originally was not planning on reflying this core, as it was their best flight tested article and they did not want to risk loosing the value of having it for future reference, but then a later landing with another core was a bit rougher than anticipated and they did not feel comfortable with the margins of reusing that core. So part of that year they were waffling on if they wanted to fly this core or not.

> Does anybody have that?

No. Because it's never been done before. We'll just have to wait and see.

But: for this particular flight, SpaceX claims to have spent 4 months in refurb, and it seems to have been very thorough. Inside information suggests that a lot of this was in upgrading things to current spec. Four months is already a significant time savings on production, which is currently said to be about a year.

I find it hard to believe that reflying hardware won't be economical. But NASA's failure to do so with Shuttle seems to have broken people's brains in this area.

>"almost one year, taking way more effort than building a new one does".

Nope-

"Next goal is reflight within 24 hours."

https://twitter.com/elonmusk/status/847594208219336705

http://spacenews.com/spacexs-reusable-falcon-9-what-are-the-...

Of course the first missions won't that effective for cost savings, but the future ones will be.

Sheesh, one step at a time, ok?

They already stated that they want to hit 24h turnaround for the F9 core within one year.