Forgot your password?
typodupeerror

Comment: Re:No, who cares? (Score 1) 260

by khallow (#48035467) Attached to: Could We Abort a Manned Mission To Mars?

Again, you claimed Apollo as an example of the superiority of flesh based exploration. When you find it it wasn't, you claim the example is irrelevant. I find your constant refuting of your own arguments a bit bizarre.

I didn't "find it wasn't". The bottom line on Apollo is that it was a national prestige projection which had scientific research as a lower priority. Despite that and various other constraints, such as the short time actually spent on the Moon, they did enough research to shut down all unmanned surface exploration by the entire world for forty years.

Comment: Re:No, who cares? (Score 1) 260

by khallow (#48032037) Attached to: Could We Abort a Manned Mission To Mars?

Yes. Which is to say, the arguments for electric light won us over when we saw it in action, and electric lighting inevitably replaced the technology that preceded it. Just as robotic exploration has now replaced the technology that preceded it (human based exploration).

You are conflating vastly different meanings of "as a species". The species didn't invent the lightbulb, and the species didn't adopt the light bulb. Most of humanity didn't even have a thing to do with the creation of the societies that made invention of the light bulb possible.

And your "inevitable" replacement of previous technologies by the light bulb took generations. It was in high volume use long before the majority of humanity ever used one.

Finally, we go to the painfully obvious point that only a few people had anything at all to do with the invention of the light bulb. It didn't take humanity to make a light bulb, it took a few people working in labs over the course of 50 or so years to do so.

Currently, even putting things into Earth orbit take considerable economic effort. That will change just as it has for the past few centuries. Eventually, it'll drop to the point where a group with sufficient economic resources to make it happen will do so.

The discoveries (as far as it goes) weren't enough to justify the cost. The purpose of Apollo was to beat the Ruskies to the moon. Rumour has it that Kennedy was presented with a proposal to send a probe to Mars, he rejected it in favour of a manned mission to the moon. Thought it was more showy. Upshot is, any science that happened was merely incidental, and none of it in this century requires or recommends itself to having a human physically present on the moon. Want to place a mirror on the moon? Send a probe. Need a moon rock sample? Land a probe, get a sample, blast off back to earth.

All of which is completely irrelevant to both the capabilities of manned space flight and the capabilities of future groups of people to engage in manned space flight. The "incidental science", for example, happened and we can use that as an example of human endeavors in that sort of environment no matter the motives of the time.

As the questions at the end of your post, they are remarkable only for their lack of ambition. For example, you could have asked instead "Want to establish a colony on the Moon?" which is a bit more involved than just picking up a few more rocks from the Moon. Well, you'll need people for that.

Comment: Re:There Ain't No Stealth In Space (Score 1) 442

by khallow (#48031927) Attached to: The Physics of Space Battles

Going from 3,000 K to 2,000 K is "cooling".

Going from 3,000 K to 3K is also cooling. This is what I'm speaking of. Do you have a point to your argument? Perhaps you ought to look at actual video of rocket plumes in space. They really do cool very rapidly to below ionization temperatures.

PHYSICS says that the exhaust will expand. Eventually the exhaust cloud will be larger than the area covered by the "shield". At which time the exhaust will be visible.

How visible? You're chasing a straw man here. I'm not interested in perfect invisibility, I'm interested in "stealth", making a vehicle hard enough to detect that it can sneak up on a target and get within range of making a useful attack.

Comment: Re:There Ain't No Stealth In Space (Score 1) 442

by khallow (#48031877) Attached to: The Physics of Space Battles

It is instead a free expansion of gas and that leads to NO cooling.

That is incorrect. What happens is that as the exhaust plume expands, the motion becomes correlated. Everything has random motion, but only particles moving in the same direction will stay near one another. Thus, the random motion of heat translates naturally into translation motion. That's how the temperature will drop from expansion.

Comment: Re:There Ain't No Stealth In Space (Score 1) 442

by khallow (#48023383) Attached to: The Physics of Space Battles

Explain how the exhaust will cool to background radiation levels.

The assumption here is that the exhaust is in the form of a gas. Once it passes through the constriction of the rocket nozzle, it expands (the effect is to turn thermal random motion of the particles of the exhaust into directed velocity). Expansion of a gas causes cooling. After leaving the bell, there are no more restrictions to expansion of the gas aside from the small amount of matter in space.

In addition, the much increased surface area of the exhaust plume allows for greater radiation of heat to space.

That is what you posted. And they will take 300 years to reach the Oort cloud.

And again, so what? I already explained why I posted that. No one is going to use the behavior of Voyager spacecraft, particularly beaming a highly directed signal at the target you're trying to sneak up on, as a strategy for stealth. It was an inappropriate example for the article to use. That's the only reason I mentioned it.

You claim that a cloak of invisibility is possible.

I say that physics says it is not.

Then use physics to make that argument not assertions that I brought up Voyager. And please characterize my arguments correctly. I'm not saying that invisibility is possible, but rather that stealth is.

I say that if it was an invisibility cloak you wouldn't need tactics to take out anyone who isn't blind. The cloak would make you invisible. They would not see you. Tactics do not beat physics.

I think you're starting to see my point. Stealth isn't perfect. It would be relatively hard against large, sensitive detectors. But you can't haul those on a high acceleration warship (unless you're doing some sort of swarm-based sensing). Disable the detectors and you're left with far weaker systems. The methods we've been discussing would be much more effective in that case.

It's also worth noting that even rudimentary stealth efforts might be effective against self-guiding weapons or enemies who don't happen to have access to good sensory equipment. It can provide an edge or improve survivability.

Comment: Re:See mom? (Score 1) 113

by khallow (#48023187) Attached to: Mystery Gamer Makes Millions Moving Markets In Japan

Day traders profit off of the day to day fluctuations of the market, and government policies can and does have both immediate and systematic effects on those fluctuations.

Lots of things can cause fluctuations even the entry of new players or someone deciding to change the size of their investment in a corporation. Government interference is far from unique in this regard.

While it is true what day traders do isn't rape and pillage, the analogy I would equate to is accepting stolen or counterfeit goods.

This analogy doesn't make sense at all to me. I don't see that it is any better to pretend a government policy or regulation change didn't happen.

What I was saying is those things are not signs of not being an idiot, but signs of not having much empathy.

Which is part of the lesson IMHO. Training like this can help you turn off empathy when it is inappropriate and/or unhealthy for you.

Comment: Re:See mom? (Score 1) 113

by khallow (#48019919) Attached to: Mystery Gamer Makes Millions Moving Markets In Japan
The previous AC was speaking of stock markets. Those are relatively free.

In the absence of a free market, government sets the precedent that it's ok to violate the rights of others to further one's own interests. Being successful under such conditions is not a good indicator that one is intelligent or competent (i.e not an idiot), but whether one possesses the same traits as a psychopath - willing to exploit whatever loophole that exists, violating any rights that gets in the way, ignore the loss of liberty for all. "I got mine, screw yours"

While I agree, I don't see the connection to the discussion of day trading. It's obviously not particularly moral, but it's not taking candy from babies either. And if this guy is as good at it as he claims, then that's a better thing to be doing from his bedroom than a lot of stuff I can think of. As to his mental outlook, I think that's actually two useful lessons for us all.

First, knowledge learned in one area can be applied elsewhere sometimes in surprising places or ways. Who knew that playing a game could help you become a vigorous trader on a stock market? Well, now we know.

Then there's the mental attitude he speaks of. It takes a considerable mental adjustment to be able to accept such a high rate of failure as routine and develop a feeling for when something has failed or succeeded to the point of abandonment. Sure, it's not so great an outlook for child-rearing, but there's plenty such as trade or commerce of just about anything, where this is a useful approach.

Comment: Re:I would like to see a return... (Score 3, Informative) 120

by khallow (#48018643) Attached to: Apple Faces Large Penalties In EU Tax Probe
"to how taxes were done" by whom? When I see stuff like this, it's usually from a US citizen who doesn't have a clue what sort of loopholes were around 50 years ago.

We could have socialized medicine in the US if we could get this money.

Or we could have something useful. Or just not collect the taxes in the first place, if that's the best you can do with it.

Let's also kill right now, the notion that corporations are persons.

Definitely from the US. Well, I guess you'll be pleased to find out that everyone including the US Supreme Court already agrees with you. Corporations aren't people and there just isn't any disagreement on that. OTOH, corporate personhood is a legal fiction used to insure that the people involved with a corporation receive proper protection under a variety of developed world legal systems, including the US.

It's a fallacy designed to be pro-business.

Let me note that pro-business is far less harmful and crazy to human society than anti-business.

Comment: Re:There Ain't No Stealth In Space (Score 1) 442

by khallow (#48018517) Attached to: The Physics of Space Battles

You are claiming that. But you have not explained how it would happen.

You just quoted my explanation "rapid expansion of the propellant in a vacuum in addition to the above mentioned thermal radiation". My point was not that rocket exhaust is instantly invisible, but rather it cools off very quickly and is not as visible as claimed by you or the link that's been passed around. "Glow" in particular implies ionization. That goes away particularly fast in space.

Like your previous example of Voyager. Which you did not like once I pointed out that it would take 300 years just to reach the Oort cloud.

I didn't bring up Voyager, that was brought up by the article on the impossibility of stealth in space. Here's what that article stated:

As of 2013, the Voyager 1 space probe is about 18 billion kilometers away from Terra and its radio signal is a pathetic 20 watts (or about as dim as the light bulb in your refrigerator). But as faint as it is, the Green Bank telescope can pick it out from the background noise in one second flat.

Note that there's no mention of the facts that the signal in question is highly directional and narrow bandwidth, while the Green Bank antenna is massive. The observation is irrelevant to any attempt at stealth.

Tactics do not beat physics.

You first have to show that.

Nothing succeeds like success. -- Alexandre Dumas

Working...