11–20 of 142 posts
My favorite way to describe orbits is 'constantly throwing yourself at the ground but moving so fast that you just keep missing', hence the constant free-fall/zero-g.
"[100Km altitude] is the equivalent of the starting line of a race. The race itself is the kinetic energy." Did you get that, Jeff? The truth is, they have both achieved an astonishing amount.
My favorite way to describe orbits is 'constantly throwing yourself at the ground but moving so fast that you just keep missing', hence the constant free-fall/zero-g.
"The knack of flying is learning how to throw yourself at the ground and miss." ~ Douglas Adams
"[100Km altitude] is the equivalent of the starting line of a race. The race itself is the kinetic energy." Did you get that, Jeff? The truth is, they have both achieved an astonishing amount.
Comparing apples (going up then down) to oranges (getting into orbit). Pretty awesome to see these guys putting their cash towards this! Hope a rivalry heats up and I can goto Mars for $3.50.
My favorite way to describe orbits is 'constantly throwing yourself at the ground but moving so fast that you just keep missing', hence the constant free-fall/zero-g.
"The reason it's hard to get to orbit isn't that space is high up. It's hard to get to orbit because you have to go so fast."
But, I'm just in awe and I keep thinking 'how does he do it?'.
He's running two intensely technical and risky companies. Yet he seems involved in and knowledgeable about every aspect of their operations and tech. And finds the time to write a post like this before what is an incredibly important and defining endeavor.
What can us, mere mortals learn from him? We can't change our baseline raw intelligence (which effects how quickly and deeply you can learn new things), but are there other patterns we can replicate in our lives?
Clearly this man's intellect is through the roof. Reading this post and him explaining these concepts in such first-principle terms (despite not being a physicist/rocket engineer) indicates his in-depth understanding (nothing new there). I know he has a Bachelors in Physics but bear with me. But, I'm just in awe and I keep thinking 'how does he do it?'. He's running two intensely technical and risky companies. Yet he…
One thing I've not seen mentioned in the coverage so far: how much payload is sacrificed by the need to keep fuel in reserve for the return to base? I'm guessing the sacrifice is roughly equal to the mass of unburnt fuel in the booster at the point of booster separation, but don't much trust my intuition on these things.
> how much payload is sacrificed by the need to keep fuel
> in reserve for the return to base?
A more detailed answer is that building a system which can be reused is an economic proposition. So that the Falcon 9 can lift X Metric tons to orbit for $Y. The way in which they keep the value $Y low is by re-using the first stage. Every satellite project knows the throw weight of all the common launch vehicles and their cost per kilo. And that is how you plan you satellite design.
Now at the moment SpaceX gets 9 merlin engines and the first stage booster back for "free" (which is to say that the cost paid assumed it would be consumed in the launch) but as they learn what they can do they will use that cost savings to offer cheaper launch services (more business) until they have a full launch schedule and then keep any excess value for re-investment.
But an interesting question is this, given that they have a "used" first stage, who would be willing to launch on it? It has no track record and no reliability statistics other than it worked at least once before. To develop that information you need to re-launch them. And I'm hoping that SpaceX will make available some higher risk but lower cost "seats" on those test flights.
Clearly this man's intellect is through the roof. Reading this post and him explaining these concepts in such first-principle terms (despite not being a physicist/rocket engineer) indicates his in-depth understanding (nothing new there). I know he has a Bachelors in Physics but bear with me. But, I'm just in awe and I keep thinking 'how does he do it?'. He's running two intensely technical and risky companies. Yet he…