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Comment: It's all about the physics stupid. (Score 1) 72

by DerekLyons (#49365843) Attached to: SpaceX's New Combustion Technologies

So, when the Wright Brothers were building their plane you were standing their telling them it couldn't be done eh?

Nope. Unpowered flight already existed by the time the Wright brothers headed to Kitty Hawk, and powered flight was right on the edge of possibility. The drives you propose, aren't. The problem is, you don't grasp that fundamental difference and thus assume that people who aren't as egregiously ignorant as you are the ones in the wrong.

Just because there isn't off the shelf technology at the moment doesn't mean we shouldn't strive for longer term solutions to interplanetary travel.

True. But those solutions must fall within the bounds of physics and chemistry - and nuclear reactors and ion engines, for the reasons I outlined, don't. Absent new physics, they never will.

Regardless of the propulsion system, having electrical power, lots of it, is the difference between coasting from A to B in a tin can vs something that could actually be called a Ship.

Only to someone who doesn't grasp physics in general as well as the mathematics behind orbital mechanics. Absent new physics, all vehicles in space are going to spend far more time coasting than under power.

Comment: Re:Wrong Focus (Score 1) 72

by DerekLyons (#49365115) Attached to: SpaceX's New Combustion Technologies

It's time to stop jetting around the solar system on chemical rockets. Designers and funding should be directed towards lofting and running multi-megawatt reactors. They would be used to power multiple ION engines

Yes... let's develop heavy power sources in order to power weak propulsion systems - what a great idea! Multiple ones aren't much better, you still need to power them, and you have to multiply a small number (thrust per engine) by dozens (or more) to get a usefully large number (thrust) for any significant spacecraft. (Which will still be far short, by orders of magnitude, for a useful size for a manned mission.)

Their extraordinary ISP is very attractive from an academic point of view and when considered in isolation... but real world vehicles aren't academic and the engines are but one part of the whole vehicle. When you start to design an actual vehicle and an actual mission, their extraordinarily low thrust-to-weight ratio precludes them from being useful except in a few very specific circumstances.

Comment: Re:Why does it need to be replaced? (Score 4, Insightful) 132

by DerekLyons (#49363319) Attached to: Russia Wants To Work With NASA On a New Space Station

As an engineer I want to reuse and expand and not throw anything away.

If you were truly an engineer (a real one, not just someone with an overinflated title), you'd know that things age and wear out.

NASA can't build tin cans that can survive in space for a hundred years? There are planes from WW2 that are still flying and those rattle.

A real engineer grasps the impact of parts count and complexity. Not only is the ISS not just a "tin can", those planes are orders of magnitude simpler than the ISS.
Not to mention that those planes take hundreds of man hours a year to maintain in flyable condition - and man hours in space cost tens of thousands per.

Things get at least a hundred times cheaper when they don't have to survive the stresses of liftoff.

Sure, as any engineer knows, you can easily manufacture things given enough infrastructure. Since you're an "engineer", you should be able to estimate the cost of developing a (currently non existent) weightless capable factory complex, and the costs of placing hundreds to thousands of tons on orbit, and the ongoing costs of logistics, support, and maintenance needed to produce those "hundreds of times cheaper" parts. You'll also be able to understand that a space craft is made of hundreds of different kinds of materials, only a few of which are amenable to recycling.

Comment: Re:The Hillary email thing is a nonissue (Score 1) 257

by DerekLyons (#49360413) Attached to: Iowa's Governor Terry Branstad Thinks He Doesn't Use E-mail

She has every right to delete email she sends and receives. Saying she doesn't is a slippery slope towards making all of us responsible for data retention wrt our own email.

That's the thing, these weren't her emails. They were the official communications of an elected official, OUR emails.

Comment: Re:We should lobby to break the cable companies (Score 4, Insightful) 535

Middle of nowhere? He lives in a county with 250k people and about an average of 650 people per square mile.

Yes, the middle of nowhere. (I live in Kitsap County as well.) That average is misleading because most of the people are concentrated in one of three major 'metro' areas, much of the county is low density or practically empty. (And he lives in one of the low density areas, in an area which county residents regard as being 'backwoods'.)

Comment: Re:No one is forcing anyone to do anything (Score 3, Informative) 535

DSL in his area is CenturyLink. The DSLAM that coves his house is in "Permanent Exhaust" meaning it's oversubscribed so far even CenturyLink won't add more subscribers, and they have made the business decision to NOT increase the bandwidth to the DSLAM cabinet further to be able to support more hardware. I.E. "I'm sorry, we're full. No, we're not adding any more capacity. Ever. Goodbye."

I live in Kitsap County and I looked up his address, and I can't say I'm surprised. He lives in a very low density area, and given current land use restrictions, that's not going to change. There's no money to be had in expanding capacity.

And ComCast is flat-out refusing to service his house/area entirely. Full-stop: Since they can't charge him the full line-extension fee ($50-60k) the portion they have to pay by law is too high so they'd rather refuse him service entirely. Welcome to the edge-case downside of regulation preventing the full cost from landing on the end-user.

No, welcome to the "edge case" of living in a very low density area outside of town rather than in a suburb.

Point-to-Point wireless no longer covers his area due to a new tall building being built between their regional tower and his subdivision.

He doesn't live in a subdivision - he lives in the woods outside the built up area of town.

Seriously, I've said it three different ways but I'll repeat it a fourth time because it's important to grasp - he lives in very low residential density area outside of town. He doesn't live in the suburbs or a subdivision. I give and grant that Comcast is incompetent - but his options are narrowed and/or blocked as much by the fact of where he chose to live as by any law or regulation. The north end isn't Palo Alto or Mountain View.

Comment: Re:Gen Con? (Score 1) 873

by DerekLyons (#49339131) Attached to: Gen Con Threatens To Leave Indianapolis Over Religious Freedom Bill

Not really. Thirty years ago Gen Con was indeed all that and one of the premier cons of nerd world. Nowadays, with the rise of Multiple Comic Conventions, multiple anime conventions, and multiple incarnations of PAX... it's decidedly in the second tier and edging towards irrelevance.

Comment: Re:The design is relatively simple (Score 1) 339

by DerekLyons (#49333589) Attached to: Feds Attempt To Censor Parts of a New Book About the Hydrogen Bomb

The design of the bombs is not the problem.

Have you ever actually studied nuclear weapons design? (By which I mean the unclassified stuff that's available.) Yes, designing the bombs is a problem, especially if you want anything more than a very crude, large, and heavy device. (One that's virtually undeliverable by modern standards.) It's not an insurmountable problem, granted, but is a problem.

And it's an even bigger problem for thermonuclear designs.

There's two ways around the problem though... the first is to explode a lot of bombs and thus gain experience and information. The second is to "borrow" the experience and information from somebody else. The difficulty of obtaining sufficient material makes the first impractical in many cases, and what the feds are trying to do is make the second as difficult as possible as well.

Comment: Re:Wouldnt NiFe be a better battery chemistry here (Score 1) 184

They're going to be constantly replacing LiOn packs on any appreciable sized system. Why not go with a NiFe battery system that will last for fifty years?

Because Elon Musk owns Tesla - and a giga factory designed to turn out LiOn batteries like Carter's churns out little pills.

Comment: Re:Me depressed now (Score 2) 56

by DerekLyons (#49324017) Attached to: NASA's Abandoned Launch Facilities

But at its heart it's the result of the dramatic slashing of the NASA budget after Apollo, the end of the "space race," and constant political interference (mostly in the form of pork projects that Congressmen wanted NASA to lend credibility to).

Well, no. Not really.

Pretty much all of the Saturn V pads and buildings are still there, and still in use - having been repurposed multiple times. The Saturn I pads were abandoned in the late 60's because nobody thought we'd ever use them again. (And then along came Skylab.)

Other pads were abandoned for a wide variety of reasons... For example, we don't need as many as we used to because we don't have vehicles sitting on the pad as long as we used to. Others were abandoned because rockets don't blow up nearly as often, so we don't need "hot spares". Others were abandoned because the booster was replaced by a different one and the activity shifted to a different pad. Yet others because not only do rockets not blow up so often, their payloads fail less often and have a longer lifetime, so we don't need much of the the frenetic launch pace of the 60's. (Or multiple combinations of these.) Etc... etc...

The number of pads required aren't pushed by raw budget, they're pulled by user requirements. Now, I won't disagree that budgets effect the pull rate, but so do a variety of other factors.

Comment: It's all about the perception. (Score 2) 141

by DerekLyons (#49322849) Attached to: "Google Glass Isn't Dead!" Says Google's CEO Eric Schmidt

People where hostile to people with Cell phones in the 1980's, In college back in my day, if a student went to class with a Laptop we were hostile towards them. Portable technology takes a while to get into the culture.

Walkman's and portable CD players too... However the feeling was less about the technology or being portable (or new), and more about the price tag and what it was perceived to say about the owner. People walking about with expensive portable technology were classed alongside those walking about with expensive wristwatches - pretentious yuppie assholes with more money than sense.

You saw the same thing when iPods first hit the market, and again with iPhones, and again with iWatch.

Comment: Re:Batching and operations research (Score 1) 110

The biggest threat to Amazon right now is companies like Walmart realizing that their stores can also serve as warehouses and getting their IT up to snuff.

There's a lot of retailers who have realized it - and who have gotten their IT up to snuff and offer "order online, pickup in store in an hour" services. (Concentrating on getting the customer in the store isn't a mistake.)
The problem for these retailers isn't IT (as it so often isn't), it's the infrastructure and overhead involved in setting up an Amazon delivery type of operation. Amazon already has the back-end, a very efficient warehousing, picking, and packing operation - all they had to do was add to front end (dispatch, vehicles, and drivers). Not only does Walmart not have the back or front ends... a retail store isn't a warehouse, and the picking and packing will be much more difficult (and labor intensive, since they can't use the robots and conveyor systems that Amazon does). Amazon could simply build on their existing operations, Wal-Mart would have to start from scratch and be fighting with one foot in a bucket of cement.

What good is a ticket to the good life, if you can't find the entrance?