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Comment Re:3500 degrees (Score 1) 81

Because when you mix 2 things at temperature T, it doesn't make a thing at temperature 2T. Don't mistake temperature for energy.

Wait, wait, wait.. Are you guys thinking about is a physical connected heat transfer? Then yes, adding two sources at 1000C will not get the temperature above 1000C (you need an active heat source and insolution for that). But this isn't a physical heat transfer. It is an energy transfer over light, and this case the new matterial unconnected to the old can have different material and different insulation. Using physical connected heat logic makes no sense here.

Comment Re:3500 degrees (Score 1) 81

Because when you mix 2 things at temperature T, it doesn't make a thing at temperature 2T. Don't mistake temperature for energy.

?? What are you smoking?

Of course it isn't. But if you add two accelerations to eachother you get twice the acceleration. The stable temperature is based on where the acceleration and deacceleration of temperature meet (how much is added and how much is lost). When you add more, that balance changes upwards.

Comment Re:3500 degrees (Score 1) 81

I had the same question. It seems to me that the only limiting factors would be total power (shouldn't it scale linearly with the number of bulbs?) vs. the rate at which heat is removed from the target location via thermal radiation or convection.

I suppose you'd also have to consider what happens when your target vaporizes, since you'd no longer have a solid object at the focal point to absorb the radiation.

That is also the only way a relation to the filament material would make sense. If the target is made of the exact same material, it would vaporize at the maximum temperature of the filament. But why would it be the same material?

Comment Re:Nope (Score 2) 81

optimal setup for concentrating natural sunlight

But it's not. Sunlight is for all intents and purposes collimated due to the extreme distance of its source. While these lamps can be "swivelled (sp?) to concentrate light on a single spot", that will tell you little about the setup applicable for use with sunlight.

Have you heard about mirrors? And mirrors on swivels?

See also Solar power towers

Comment Re:3500 degrees (Score 1) 81

That's a lot really. What kind of lights are these?

The summary obfuscates this but whatever the amount of incandescent bulbs you are focusing on the same spot, you cannot get a temperature that is higher than the filament in the bulb (the black box temperature of the bulb). And 3500 is a lot for an incandescent bulb.
Maybe it's another kind of lighting then. Like a combination of different LEDs.

Okay. I will bite: Why not? You add energy from multiple lamps. Light superpositions and photons excites what they hit if they are absorbed, because they can't really do anything else. The maximum possible temperature at the focal point, shouldn't have anything to do with the original material.

Comment Re:The actual real problem with Mars... (Score 2) 85

The profit (a minority of their profit, it should be added) is coming from saving taxpayers money. What the heck is your problem with that?

If they were making some amount of launches cheaper - sure - but that's not the case.

Yes, it is the case; they cost vastly less than ULA.

Comment Re:The actual real problem with Mars... (Score 1) 85

What I *do* have a problem with is him parlaying this success into a full blown cult of personality

I'm sorry, I must have missed the speech where Musk announced that he is the savior of humanity and its new lord and master.

I'm sorry it gets under your skin that people appreciate the man and what he's doing, but that's hardly something he's been actively "parlaying this success into".

Comment Re:Maybe I'm missing something. . . (Score 2) 85

Most of SpaceX's launches are for private companies. And their real profit plan is satellite internet; these random couple dozen launches per year for the government and private companies is nothing compared to the value of being able to provide cheap high speed internet access everywhere on Earth without having to lay wires. But that requires thousands of satellites to be launched.

Interestingly enough, this also appears to be Blue Origin's profit plan, via their work with OneWeb.

Comment Re:The actual real problem with Mars... (Score 4, Insightful) 85

What's the problem with SpaceX getting government launch contracts? No, seriously. They're charging less than ULA and thus saving the government a ton of money. What's your huge problem with saving money and having the money that is spent go to a company that's focused on great things rather than some conglomerate of huge military-industrial giants?

I've never understood this animosity.

Comment Re:Flaws.. (Score 1) 70

Perhaps ebay have become aware of a security flaw in the keyfob, and are thus trying to migrate users away from them?

Their flaw is that they are literally unbreakable, so they are moving to something entirely trivial for most big interested parties to intercept and decrypt. I wonder why?

Comment Re:think of the children! (Score 3, Interesting) 146

Actually yes. Scientific or not, a list short enough for kids to learn in grade school is a damn good idea

Well, then, it's time to start teaching that there's only 8 rivers in the world, and all others are dwarf rivers and don't count as rivers. And 8 bones in the human body, the rest being dwarf bones that aren't really bones. And 8 particles in physics, and all others dwarf particles and don't count as particles. And 8 galaxies in the universe.... you get the picture.

. And for fuck's sake, Pluto and the other KBOs ARE DIFFERENT ENOUGH from the asteroids

Since we're apparently going into shouting mode, Pluto IS FAR MORE LIKE THE TERRESTRIAL PLANETS THAN THE TERRESTRIAL PLANETS ARE LIKE THE GAS GIANTS. If anything should be kicked out of the planet club, it's the gas giants.

The issue isn't whether KBOs should have their own classification. They do: KBOs. The question is whether it makes sense to group dissimilar objects (terrestrial planets and gas giants) but artificially exclude other objects in hydrostatic equilibrium, objects with active geology, internal differentiation, fluids, and all of the other hallmarks we associate with planets. Nature has given us a very clear dividing line: objects in hydrostatic equilibrium are where you go to see tectonics, mineralization, fluids, search for life, etc, while objects not in hydrostatic equilibrium are where you go to learn about the formation of the solar system, find its building blocks, learn about what life was built from, etc. Nature rarely gives us such meaningful dividing lines, but in this case, it has, and we should respect it.

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