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Comment: Re:Why let it crash? (Score 3, Informative) 23

by necro81 (#48930781) Attached to: The Big Bang By Balloon
Another Antarctic balloon experiment, BLAST, was designed for re-usability. On its third flight, the parachute failed to properly detach, and ended up dragging the telescope for more than 100 miles across the ice, mostly destroying it.

This doesn't mean that one shouldn't try to recover and reuse experiments, but it does present new program-level risks.

The answer as to "why don't they?" could be as prosaic as: they didn't get funding for a multi-year, multi-launch program, or couldn't squeeze the reusability and refurbishment into their program budget.

(For those interested, that third mission was the subject of a neat documentary film.)

Comment: Re:No way! (Score 1) 512

by necro81 (#48883713) Attached to: Senator Who Calls STEM Shortage a Hoax Appointed To Head Immigration
If there was any justice and sense to the English Language, "common sense" would be a curse word and shunned in polite conversation. Politicians, especially, have bastardized the use of the term for their own ends such that it hardly has any meaning aside from doublespeak.

I find this to be a fun game to play: anytime a politician starts talking about "common sense," replace it in your head with some sort of expletive. My preference is "Fucking Shite", as in

We need Fucking Shite solutions to our problems, not political speeches meant to ignite class warfare

-Rep Martha Roby, (R-AL)

This makes looking through a copy of Thomas Paine's pamphlet on the subject particularly amusing.

Comment: Re:It was the press coverage that was the disaster (Score 1) 76

by necro81 (#48883585) Attached to: The Camera That Changed the Universe

I recall reading about the mirror when it was being made, the precision with which it was polished was mind bogglingly accurate

Be careful how you use the terms "precision" and "accuracy," because they have very specific meanings to engineers and metrologists. Yes, the precision was mind-boggling. The accuracy, on the other hand, well...

Comment: Re:It was the press coverage that was the disaster (Score 1) 76

by necro81 (#48883537) Attached to: The Camera That Changed the Universe

Despite the slight change in the curvature of the main mirror, Hubble's images were pretty amazing

Amazing maybe, but far below what was promised. There isn't any way to gloss over the fact that the project managed to screw up the single most important component in the telescope. The mirror ended flawed and in orbit not because it was too technically challenging, but because of arrogance, sloppiness, and poor oversight. The taxpayers have a right - even today - to be pretty steamed about it.

Imagine if someone sold you a sportscar, promising it would handle like a dream and hit 200 mph on the straightaway. When you finally receive it and test it out, it shimmies like a banshee and can only manage 100 mph. When you call to complain about it, you find out that during construction, the technicians got drunk one night, ground the cam shaft wrong, and left out one piston. The company sold it to you anyway, not because they were trying to cover anything up, but that they simply didn't know anything was wrong, because they'd never bothered to test drive it before shipping it. Your argument is that we should still have been happy to have it because it's better than the Honda Civic we were used to driving. And, given the etymology of the word , "disaster" is a good choice.

Comment: Re:B-but externalized costs don't real! (Score 4, Informative) 202

by necro81 (#48813577) Attached to: Obama Planning New Rules For Oil and Gas Industry's Methane Emissions

Simply changing EPA rules by Presidential decree is dictatorial

The EPA is empowered, by Congress, to make such rules. The EPA falls under the executive branch, and so takes direction from the President, within the broad legislative mandate to protect the environment. In any event, the President hasn't actually issued new rules by decree - he's got certain goals, and has set the EPA to the task of actually drafting the rules and regulations through their normal process (which, for better or worse, includes lawsuits).

A President can't drop such regulations by decree, because that would violate the EPA's mandate and other existing laws enacted for the environment.

Comment: Re:FRAM vs NAND (Score 2) 52

by necro81 (#48774615) Attached to: NASA Update Will Deal With Opportunity Flash Memory "Amnesia"
I did a bit of reading on the subject from TI, which has FRAM integrated into some of its MSP430 microcontrollers. If anything, the technology seems to be well-suited to the space environment, because bit storage is accomplished via a crystal structure change (polarization), rather than through charge storage.

Comment: Re:Thanks, assholes (Score 1) 573

by necro81 (#48753705) Attached to: Gun Rights Hacktivists To Fab 3D-Printed Guns At State Capitol

I believe that there is one very high end 3D printer that has made metal weapons that work very well

That weapon was made using a DLMS (direct laser metal sintering) machine, which fuses metal powder using a powerful laser. This kind of machine goes for upwards of $1million, and isn't exactly turnkey. (I know: my company has one, and although it's amazing, it tends to not produce a usable copy of a new part until the 2nd of 3rd try.) Plus, it required a fair bit of post-machining.

Your example reinforces my point - if you want a "reliable and somewhat accurate weapon", you use metal, and metal rapid prototypers are not hobbyist equipment, and may not ever be. Plus, even if it were, you still need a reasonably well-equipped machine shop to finish the metal parts and assemble a working gun.

Comment: Re:That's not the approach you want to take for Ma (Score 1) 151

by necro81 (#48745751) Attached to: In Daring Plan, Tomorrow SpaceX To Land a Rocket On Floating Platform

Do a powered descent with the Dragon Capsule, and return to orbit with Dragon under its own power to rendezvous with the upper stage that will bring it back to Earth

Dragon does not have enough fuel to both land and launch again. SpaceX hasn't demonstrated that it has sufficient capacity to even do a powered landing. I'm not saying itcan't, but you can't look at a Dragon capsule and consider it a vehicle capable of powering itself to orbital launch velocity, even on Mars.

Comment: Re:Thanks, assholes (Score 4, Informative) 573

by necro81 (#48745495) Attached to: Gun Rights Hacktivists To Fab 3D-Printed Guns At State Capitol

3D printers will allow anyone to print a reliable and somewhat accurate weapon cheaply one day. At the moment they are still expensive, but won't stay that way for long

The notion of a "reliable and somewhat accurate weapon" coming from a $2,000 FDM (fused deposition modeling, i.e., plastic extruder) is laughable and drastically oversells the ability of the technology. Oh, sure, you can produce a gun today that'll kill someone, but don't expect 3D printers to enable the next Continental Army.

Perhaps a gunsmith could say otherwise, but my understanding is that a "reliable and somewhat accurate weapon" requires metal. 3D printing of metal is going to stay expensive for a long time, maybe for good, if only because the power it takes to sinter/melt metal is high and isn't going down. A 40-kW laser in every tinkerer's basement isn't likely. I've seen FDM-like metal printers that are more or less wire welders on an XYZ base, but the results leave much to be desired. Even then, a printed metal part will still need a decent amount of post-machining, in which case you may be better off fab'ing your gun from solid stock.

(I use 3D printing (FDM, SLS, DLMS) in my day-to-day job, have experience with hobbyist 3D printers)

Comment: Re:Extending the life of Hubble... (Score 2) 97

by necro81 (#48744529) Attached to: Hubble Takes Amazing New Images of Andromeda, Pillars of Creation

In what way aren't they capable?

Well, the big one I can see is that they lack an airlock for EVAs. They also lack a cargo bay for bringing up tools and replacement parts. Lastly, they don't have a remote manipulator like the shuttle's arm, which was an essential tool for the servicing missions - first for capturing and positioning the telescope, then for moving the astronauts around.

With several launches, you could put together an orbiting service platform that contains these things. Unless things change greatly, however, the cost of putting together such a platform approaches the cost of building a whole new telescope!

I'm sure that we'll get there eventually (a LEO servicing platform), if only because fixing satellites could be a genuine business venture, but I don't think it'll happen within Hubble's remaining life.

The herd instinct among economists makes sheep look like independent thinkers.