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Background on the Falcon 9 Launch

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Re: Background on the Falcon 9 Launch

#131

Post by Retric »

blizkreeg wrote: post #17

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…

"Bachelor of Science degree in physics at Penn's College of Arts and Sciences." https://en.wikipedia.org/wiki/Elon_Musk

Sure, he does not have a MS or PHD but he was trained in physics.

Re: Background on the Falcon 9 Launch

#132

Post by ChuckMcM »

sillysaurus3 wrote: post #83
blizkreeg wrote: post #17

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…

This hero worship is utterly stupid. It's also a disservice to children. We're teaching them that there are heroes, and then everyone else. Bull. Work as hard as Elon did, and you'd make the same progress. It also required luck. No PayPal, no Elon. And there could only be one PayPal, at precisely that time in history. A better question is, why did Carmack fail where Elon succeeded? Armadillo Aerospace was supposed to…

There is one school of thought that goes that SpaceX's mission to "Get people to Mars" requires so much more than simply putting things in orbit that people set their expectations that this is only the beginning. If you set your expectations that you just wanted to get to space and straight back down again, you don't invest in things which would be helpful to a Mars mission.

So while building a resuable booster for rockets might be the entire goal of some company, for SpaceX it was only the first step in a lot of bigger goals in order to make it feasible to go to Mars. And in so doing, and creating a capability that they can sell today to fund future development.

Re: Background on the Falcon 9 Launch

#135

Post by 1stop »

marcosscriven wrote: post #108
1stop wrote: post #105

Earlier quoted context omitted.

Pretty sure inertia IS a force. But I think this point has been laboured enough. Tomayto...Tomarto.

A force is the product of mass and acceleration. Its SI units are kg.m/s^2 Inertia is an inherent property of mass. If it were the same as a force its units would be the same. So it's really not tomayto...tomato I'm afraid. It's right and wrong. You are right the point has been laboured, but it upsets me to think you would go on under this misconception.

Gravity is also an inherent property of mass... It's also a force.

Crazy huh?

Re: Background on the Falcon 9 Launch

#136

Post by aparent »

soperj wrote: post #133

"nitrogen attitude thrusters" Think that was supposed to be altitude? edit: just saw this at the bottom and it made me smile; "Apologies for any typos in the above."

Attitude is correct. It refers to thusters controlling the orientation of the rocket.

https://en.m.wikipedia.org/wiki/Attitude_control

Re: Background on the Falcon 9 Launch

#137

Post by erikpukinskis »

mikeash wrote: post #12
mannykannot wrote: post #2

"[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.

Blue Origin is cool but it's certainly not astonishing to me that a billionaire is able to send a rocket on a suborbital trajectory and recover it. It's certainly more than I've ever done by a long shot, but it's not a very interesting achievement unless you're interested in five-minute space tourism. I don't think BO's achievement here has many implications for space travel.

It's amazing in 10 years we've gone from an X-prize to do exactly that to "not interesting".

Re: Background on the Falcon 9 Launch

#138

Post by manigandham »

blizkreeg wrote: post #17

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…

Learn to stop thinking that everyone else are just "mere mortals".

We're all humans here. Productivity is a complicated output of intelligence, ambition, application, luck and financial fortune.

Re: Background on the Falcon 9 Launch

#140

Post by alerkay »

mannykannot wrote: post #2

"[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.

You're right, both achievements are huge.

That said, I'm not too sure I understand the line "the kinetic energy transfer at a 100 km reference altitude is what matters"...

What is the "kinetic energy transfer at 100km" ? Why not say that what matters is the "kinetic energy transfer", period? It doesn't make any sense to me to put it the former way.

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