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Comment: Too bad they couldn't test the escape system (Score 1) 316 316

Did this Dragon have SpaceX's new SuperDraco thrusters to allow emergency escape? It's disappointing that the rocket blew up, but it's really too bad they couldn't use this to demonstrate that their escape system works. That could have turned this from a big setback to a minor step forward in approving this thing to carry people.

Comment: Re:Voicemail considered harmful (Score 1) 395 395

I agree that it's faster for you to send a voicemail than an email. On the other hand, you don't dispute my point that voicemail is slower and more of a pain in the ass for the recipient.

So yes, voicemail is ideal for people who think that their time is more valuable than the people they're reaching out to contact. Which is to say, voicemail is the tool of choice for selfish jerks. Not that you intend to be one, but that's how it comes across to me.

Comment: Re:Voicemail considered harmful (Score 1) 395 395

Don't get me wrong, real-time voice is great for back-and-forth. But you can't do that by voicemail. All you can do is send a "we need to talk about X" ping. You say you're doing that with a followup email and text, which means the voicemail is redundant: all it's doing is forcing me to listen to you stutter for several minutes, verbally repeating a message I got with a quick glance at my phone an hour ago.

Comment: Re:Makes sense (Score 5, Interesting) 395 395

There's this amazing etiquette change going on in America today, the idea that you need to contact someone first before you can have a real-time interaction with them. You can't just show up at someone's door, you have to call first. You can't just call, you need to text first. Someday soon, it'll be rude to text without first checking someone's Weibo status or some damn thing. Our great-grandparents would be baffled.

Comment: Voicemail considered harmful (Score 1) 395 395

Recorded speech is slow, impossible to organize, and nearly unsearchable. If you're providing information to me verbally, you're wasting both my time and yours: just send me a copy of the data source you're reading from. If you're providing creative ideas, you should write those suckers down in an email or other document so they don't get forgotten or mis-attributed. If you're not calling to provide either information or creative ideas, you're not saying anything useful and I don't want to listen to your businessbabble.

Comment: Re:Don't give money to your alma mater. (Score 2) 348 348

Wow, that was the most condescending post ever. Not only am I well aware of how an endowment is operated -- this is a regular topic of faculty meetings, for god's sake -- my earlier post did assume only investment income was spent. A 3.5% return on Harvard's 1.7 million per student endowment would give an annual income of $60,000, which is equal to Harvard's tuition plus room and board. Historical rates of return for the last couple centuries are significantly higher than 3.5%, which would likely allow Harvard to keep up with inflation in perpetuity.

And by the way, I teach at a liberal arts college, but I teach physics. A liberal arts education is not the opposite of math and science: it's about creating well-rounded students who're strong in both humanities and the sciences. Since you've proven yourself incapable of either understanding a written argument or doing math, you clearly didn't get one.

So crawl on back to your troll cave, you've got nothing to contribute to this discussion.

Comment: Re:Don't give money to your alma mater. (Score 1) 348 348

... and that's great news, for a couple hundred brilliant but poor kids. But these three schools can only do so much. Meanwhile, millions of other talented and deserving students can't afford to attend college at all, or can only attend underfunded schools with decaying equipment and underpaid professors teaching classes of 500.

Comment: Don't give money to your alma mater. (Score 5, Insightful) 348 348

If you went to a Harvard, a Stanford, an MIT or a Texas A&M, and you happen to end up with more money than you know what to do with, you might be inclined to give a big pile of it to the university that got you started. And while that's a noble sentiment, you shouldn't. These places will continue turning out talented graduates no matter how much money you give them: you should give your money to a less-well-endowed institution, so that a larger number of students can get the same educational opportunity you had. Maybe your spouse went to a small liberal arts college. Maybe there's a place right down the road from your mansion that could use your help. But MIT and Stanford don't need your money, and they won't do much good with it.

A bit of data: Harvard's endowment amounts to $1.7 million per student. With a reasonable return on endowment investment, hey could quite literally abolish tuition forever if they wanted to. Just across the river is Boston University, a really excellent institution with a strong research focus and really great graduates, ranked #42 by US News. Its endowment per student is 1/25th of Harvard's.

Donating money toward improving education is a worthy goal, but don't get sentimental. Put the money where it'll do the most good for the most people.

(Full disclosure: I'm a professor at a liberal arts college whose endowment per student is mediocre at best.)

Comment: Re: Warning signs of lack of engineering (Score 3, Informative) 100 100

I don't do this for a living, so don't take me too seriously. The smaller you make the first stage, the more work must be done by the second stage, which means *it* must be bigger, increasing the useless mass that makes it into orbit. Also, the smaller the first stage is, the less it costs, so it's less valuable to recover...

You're absolutely right that there's an optimization problem to be solved here, and that a rocket optimized for first stage recovery might look very different from a stock Ariane 5 with wings on the bottom. But this rocket *does* look like a stock Ariane 5 with wings on the bottom, which makes me worry that they haven't done the math.

Comment: Re:Yes, and yes. That was then... (Score 2) 100 100

But aviation has gone backwards. When I was young, anyone with a few thousand dollars to spare could fly across the Atlantic in comfort at twice the speed of sound, and military pilots in a close approximation to space suits would be flying above them at nearly twice that speed.

What's progress? Is progress defined in terms of how fast we can get a handful of millionaires from New York to Paris, or in terms of turning an ocean into an insignificant obstacle for average citizen of the developed world? Today's airfares are about a third (in constant dollars) of what they were when you were young, and there are six times as many people flying. Turns out that the ability to fly to Paris at Mach 2 was a pointless waste of effort and money. What that changed the world was the ability to get there for less than two weeks' wages.

Comment: Re:Yeah (Score 1) 100 100

I do not think you know what a turbofan is based on what you stated.

The article mentions "turbofans" but the video at the bottom of the link clearly shows external propellers (i.e., a turboprop). It's the article that's confused, not the grandparent poster.

It does - but turbofans and horizontal flight with lifting surfaces is far more efficient than attempting to land vertically using a rocket engine, and we have 110 years of experience landing aircraft horizontally, or if you want to combine total experience, probably approaching on a million combined "man years" of experience landing aircraft

SpaceX has an actual flying reuse system that might or might not work. TFA is discussing a back-of-envelope concept that hasn't even gotten to the detailed engineering yet, much less flown. You might be right, landing with wings might turn out to be a better idea. But there's tens of millions of dollars of blueprints and welded aluminum to go before we can make an apples-to-apples comparison between them. In the meantime, SpaceX will either succeed or fail. There's no point in saying either design is "better" before that.

The price one pays for pursuing any profession, or calling, is an intimate knowledge of its ugly side. -- James Baldwin