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Comment Re:Economics of that stunt are dodgy (Score 4, Insightful) 206

For the Merlin 1C, the only difference with the vacuum (second stage) version is the nozzle - a much larger expansion ratio. Other than the nozzle, they're the same engine.

The Merlin 1D variant is more deeply throttleable on the second stage, but it's unclear whether this is just a configuration setting or substantive hardware differences. I would imagine the former as much as possible.

But in any event, we concur -- lots of useful things to do with engines on their last flight.

Comment Re:Economics of that stunt are dodgy (Score 4, Insightful) 206

Even if they can't recover the second stage, if they can get reliable recovery/refurbishing/reuse of the first stage that'll completely change the economic equation. Say you can reduce the second stage cost by $1m by increasing the first stage cost by $1.2 million, today you won't do that because it's a net $200k loss. If you can reuse the first stage once for neglible fuel costs it becomes a (2*$1m - $1.2m)/2 = $400k profit per launch. If they can do it five or ten times, it's even more profitable. So I think there's a lot of potential improvements just redesigning to take maximum advantage of first stage reuse by making the second stage do less and cost less.

Also worth pointing out that those first-stage engines will have a limited number of flights they're good for. So on it's last flight, you stick the engine in a second stage. After all, you've got to get rid of your expired engines somewhere, so they may as well go in a second stage as a junkyard somewhere.

Each "time's up minus one" first stage yields nine expendable second stage engines, sorta kinda for free.

Submission + - Parse.com shutting down -- Thanks, Facebook. (parse.com)

waimate writes: Parse.com, a popular BAAS (back-end as a service), has fallen prey to Facebook. Declared by Fast Company as one of the top 50 most innovative companies of 2013, committed users shuddered when it was purchased by Facebook soon after. Today the other shoe finally dropped, when Facebook announced they are shutting the service down, leaving thousands of users scrambling for a viable replacement. It calls into question to what extent developers can trust *AAS providers, while at the same time creating an opportunity for a vendor to deploy a Parse.com compatible service. Many other service provision offerings exist, but none quite the same as Parse. Thanks for nothing, Facebook.

Comment Re:Soap Box time! (Score 1) 271

If I follow your logic, your hang-up is on the fact that "annual" implies 1 year, and raising something to the power of 1 is not raising it at all, and thus non exponential. But you're wrong. Lemme give you an example: e=mc^2. ARGH: Einstein was wrong! If you measure c in "light years per year", then c becomes 1 and 1^2 is still 1 therefore the formula is misleading! Nonsense, right? Unfortunately, so is your argument.

You're confusing something which is exponential across a number of time periods, versus the size of each time period when measured in years. Stop getting so outraged that t=1 because it doesn't. T is the number of intervals. 1 is the size of the interval when measured in years.

Primary school stuff.

Comment Computational Thinking (Score 4, Interesting) 212

This is a man standing too close to the forest to see the trees. He's right, but also completely wrong.

What is being taught is "computational thinking", not coding. Coding is just the conduit.

I've seen the stark difference in my work with primary and junior high kids (Scratch, Python, Javascript), where some kids learn sufficient language to enable them to do a bunch of neat things, but *still can't do it*. They're not making the neural connections between "here's a bunch of capabilities I have at my fingertips", and "here's how I put my capabilities together into a structure of my own creation to achieve my goal".

It's a skill that has application far beyond the keyboard. It's not about learning the syntax of a for-loop, it's about the epiphany that follows. Seeing a kids face when they (all too rarely) get it that they've become wizards and the sky is the limit, is priceless. They are visibly empowered and their view of their relationship with the world around them alters.

*That's* what it's about.

Comment Re:Modula-3 FTW! (Score 2) 492

Agreed the verboseness argument is bogus, otherwise the whole debate would consist of COBOL people on one side, and APL people on the other. They are at opposite ends of the spectrum of verboseness, and both languages largely suck, but for different reasons.

Comment Re:Modula-3 FTW! (Score 3, Informative) 492

+1 to parent. Strong typing raises compile-time errors that otherwise would end up as pernicious run-time bugs. That means less time debugging and more reliable software. It's the total opposite of the sort of hippie "oh man, just grow the data structure however you feel at the time" approach of Python.

Comment Re:youmail (Score 1) 237

After a few back and fourth texts .... the F&I guy would come to my house

Mmmm... couple of things here: 1) learn how to spell; it will do wonders for your credibility, especially if you live by text, and 2) learn not to finance things unless you have an ethical imperative for financing companies to profit at your expense. Yes, I know everyone does it, but everyone are stoopid.

Comment Re:Hard to beat MIT's Scratch. Free and graphical. (Score 2) 107

Scratch is awesome, and I've worked with many dozens of kids on it.

The huge conundrum has always been where to go "after Scratch". Python isn't it, because you can't easily share graphical games unless the recipient also has pyGame installed. Javascript hasn't been it for a lack of appropriate on-ramp.

But there's now a free online tutorial system aimed at "Scratch kids" who want to take the next step. http://s2js.com/ It tutors them through the bits of Javascript they need to know in order to write graphical games that'll run on their smartdevices. It's tutorial, simple development tool, private image storage, and deployment facility.

It's "Javascript as told to Scratchers".

Comment Learn assembler (Score 1) 637

Doesn't matter much which one, just learn to so some even trivial things in assembler. Then understand *this* is reality, and everything else is an abstraction.

For bonus points, then do it in hex without the benefit of an assembler to translate mnemonics into opcodes and calculate your relative addresses.

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