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Comment Re:last chance to buy quality Sharp products (Score -1, Flamebait) 41

None. Sadly, idiots like that run around screaming about Obama and how O is going to take their guns/rights.
These are the same kind of idiots that back police for killing a kid in the street for being black, but has no issues when a bunch of mental right wing nut jobs take over gov. buildings in a terrorists action, they will back it.

Comment I worked on some of this. (Score 5, Informative) 159

Many *MANY* years ago I was working as a software engineer at Philips Research in the early 1980's when they were looking into ISDN systems somewhat like DSL for the UK market - the business of sending anything over twisted pair copper is a nightmare. I wasn't directly working on the electronics (I was doing software) - but I shared an office with people who did...and they had a heck of a time characterizing the wires that their signals had to go down.

As I recall, the problems mostly come where one wire is spliced into another. Much of this infrastructure was put in the 1900's and it's horrible. Sometimes wires are just twisted together and capped, sometimes twisted and taped, sometimes twisted and just left open to the elements, sometimes they are soldered. Sometimes the places where the wires are joined gets wet when it rains. Sometimes the tightness of the twisted wire connection depends on the ambient temperature. The amount of cross-talk between wires is all over the map as different kinds of insulation was used (and much of it has degraded over the years). At the subscriber end, there were all kinds of phones being used - plus ugly stuff like "Party lines" (where two houses share a phone line!) that had been abandoned leaving extra wires in the ground that were still connected to the network.

All of those things affect the ability to get a decent amount of bandwidth down a wire that was never designed to do it. So the electronics has to be smart about the signal being reflected at each splice down the line and causing 'echoes', and designing affordable circuitry to detect and cancel those echoes was a nightmare. The amount of attenuation you'll get is all over the map - everything has to self- adjust and monitor to give it any chance of working.

So, as poor as DSL can be - it's a miracle it works at all over crappy old telephone wires.

    -- Steve

Comment whittington remains an idiot (Score 1) 309

Seriously, this guy is an idiot.
Ok, he does not like ARM. Yet, he claims that it does not have any scientific or engineering merit. Neither are accurate, or even close to accurate.
To move part of an asteroid will require a new tug. This will require new engineering that will then be used for asteroid mining. it can also be used to save the earth from an inbound asteroid.
Then you have several astronauts in space around the moon for several weeks. We have not sent anybody beyond LEO since the 70s and none for several weeks. This will require new engineering to protect the crew and will provide a great deal of science about radiation.

finally, we have the boulder itself. The astronauts will be able to work on it, and figure out a number of things: Namely how to deal in lowGs.
If we are going to mars, it is very likely that we will land and stay on one of the moons FIRST. They also have low G. So, this really does make sense.

Finally, NASA does not have to re-direct all of its resources to go back to the moon. NASA has been hard at work on developing new private space's capabilities. In particular, they have over 4 companies working on different re-usable lunar landers.

Sadly, ppl like whittington is too wrapped up in the past to think of what Eisenhower and Kennedy wanted for NASA, which was that they would go above and beyond, not just repeat.

Comment Re:Lost ability? (Score 1) 309

The problem isn't "going to the moon" - the problem is staying there long enough to do something useful while you're there. What was done in the original Moon missions could be done much more efficiently with robots.

The things we need people for is much more long-term - and the Apollo technology couldn't do that.

I don't buy the argument that the moon is a good stepping stone to Mars - the difficulty of creating and maintaining all the infrastructure to manufacture rocket fuel and get it up into lunar orbit (or back to Earth orbit) is way harder than just going to Mars.

Mars has more gravity, a source of CO2 for plants, a sane day length (also for plants), water (probably) just underground rather than in the shadow of the rim of some craters that never see sunlight (which might be kinda hard to work in, don't you think?)

At the very least, I'd want to see a robot crawl across a lunar crater and take a photo of the water ice piled up there before we made any kind of a judgement as to how useful the moon is.

The main reason I see to go there is to collect Helium 4 for fusion reactors...and then the water would be a bonus. That's a commercial opportunity that a big company could actually go and exploit.

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