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Comment: Re:Because titan has ice, pluto isn't even a plane (Score 2) 98 98

Technically the Pluto-Charon system is not a primary with a satellite, but a double system. The center of mass of the system is not within either body, but in the space between them. .

As I love to point out, the problem with this definition is that it also applies to the Sun-Jupiter system.

This is true and will remain true for another billion and a half years at which point the Sun will have expanded enough to put the barycenter under the surface of the photosphere. The barycentric point (as it is known) if at 1.068 solar radii.

The location of the barycentric point is of some interest, but isn't really very meaningful in defining the properties of two body systems.

Comment: Re:Motorcycle Safety Perceptions (Score 1) 236 236

The 6 mile wide rock from the sky? Nothing you can do about that.

Untrue. With enough detection time even very slight changes in orbit will prevent a collision. Humans need to take on the task of "sheep herding" the big risky rocks int he solar system, making sure they stay in nice stable non-Earth-intersecting orbits.

Comment: Re:Do people really take this risk seriously? (Score 3, Informative) 236 236

Right, and this is one threat that if we do detect it far enough in advance, we can actually prevent it from happening! And having a good detection system is the key, if we detect the threat many decades in advance even the largest "planet killers" can be deflected for modest amounts of money.

Comment: Re:The bases have to be built from local material (Score 1) 46 46

Wait, scratch that. The majority of the dwellings will need to be underground to avoid the radiation. Instead of a 3D printer, take a tunnel boring machine.

You can't make everything you need out of holes. Your tunnels will need doors, partitions, tables, etc., etc. No IKEA on Mars and the shipping charges are horrendous. There are lots of things besides main structural walls to be made.

Comment: Re:Cost bigger issue than sonic boom (Score 1) 73 73

Thanks for all your calculations, but you entirely neglect auditory acoustic response issues, or the fact this energy is coming exclusively in rapid rise impulses.

There is more direct information in this readily available. We read here that the
"Concorde's sonic boom noise level was 105 PLdB. The PLdB that researchers believe will be acceptable for unrestricted supersonic flight over land is 75, but NASA wants to eventually beat that and reach 70 PLdB."
The measure PLdB is "perceived level of decibels" which takes into the account that impulsive, rapid rise sounds appear louder to humans. A 105 dB sound is a very loud sound to anybody. There would be hundreds, perhaps even thousands, of supersonic flights coast-to-coast a day if this became commercial. If you were under a common flight corridor, you might hear one of these every few minutes all day long.

The NASA article discusses though the fact that aircraft design can lessen sonic booms, and that is real key to making this a viable transcontinental technology.

But where we really need supersonic flight is on trans-Pacific flights! Where are the hypersonic trans-Pacific airliner projects these days?

Comment: Re:What's with all these "kinds" of music? (Score 1) 361 361

There are exactly two different kinds of music - good music and bad music. What makes music good or bad is left up to the individual - everybody has different opinions. I'm 62, from a small town in Alabama, a child in the fifties, high school in the late sixties, college in the early seventies, and guess what? I like it all! From classical to the latest, there's good to be found (and a LOT of crap). There's even good and bad music from the same artist, e.g. Eric Clapton early was great, but kinda lame later. I usually listen to music played randomly from my collection. You could hear an old bluegrass song followed by Nirvana followed by Bach followed by a gospel song followed by a Disney tune. The only thing all the songs have in common is that they're only the good ones. On the road I listen to XM. The presets are Symphony Hall, Met opera, Lithium, Classic Rewind, Bluegrass Junction, and BB King's Bluesville.

Amen to this! I like everything - if it is good. I enjoy discovering new styles, genres, bands. I have been around awhile, but I was one of Pentatonix's first fans for example. Went to one of their concerts a few months back - Cello/beatboxing was showcased and it was cool! Check out Mattisyahu: his Hassidic/Reggae/Rap fusion is brilliant. Here's a tip - listen to an unfamiliar style/genre more than once. I listen to music from all over the world. It takes time to appreciate the nuances that each style/genre brings. (Bluegrass is one of America's greatest contributions to music.)

Comment: Re:A Lot of Software Defies Easy Explanation (Score 1) 244 244

I am a big proponent of agile methods (see the agile thread today), but here I disagree. A UI is part of the system architecture, and architecture fundamentals do need to be defined early in development (but then refined and evolved as development proceeds). Agile is definitely not "making stuff up as you go along".

Comment: Re:You cannot know *WHO* is voting (Score 1) 258 258

There is no evidence of significant voter fraud anywhere, that's why voter ID proponents never cite any real cases. The only problems with corruption of the voting system occurs when the votes are counted, or measures to deny people the ability to vote.

Comment: Re:You cannot know *WHO* is voting (Score 0) 258 258

... really I have no issue with mandatory voter ID -- you just need to severely over-engineer the solution to ensure it's not a burden on those in society with the least time/money/options/eduction.

And the fact that these voted ID laws never include proactive provisions to get IDs into the hands of all voters for free reveals their true intent quite clearly. Heck, Ohio is trying to enact a poll tax (banned explicitly by the Constitution, 24th Amendment) by requiring a voter ID card that you must pay for.

Comment: Re:A Lot of Software Defies Easy Explanation (Score 1) 244 244

I actually agree with this. The documentation does need to evolve with the implementation, and if you don't, it is as you say. But having a clear concept about how it is to be used, and working out a coherent description of using it is a very strong design tool to make a usable, understandable system.

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