Slashdot is powered by your submissions, so send in your scoop

 



Forgot your password?
typodupeerror
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. ×

Comment Re:we can't even be bothered to get that right.... (Score 1) 160

"The passengers will travel beyond the moon and loop back to Earth, spanning roughly 300,000 to 400,000 miles. "

The distance to the moon is 238,900 miles.
I'm going to go way out on a limb here and postulate that a trip AROUND the moon is going to be something more than 477,000 miles.

It depends on your frame of reference, the Moon orbits the Earth, so you have to travel to where the Moon will be when you get there, rather than where it is when you left. Then on the return you have to travel to where the Eart will be when you get there as well. Add in the Earth is orbiting the Sun and it becomes a 3 body problem and can only be approximated.

Comment Re: All in the timing (Score 1) 160

But that is not the case. It is those who attempt to defend His Orangeness that are expending vast amounts of energy, having to work so very hard to keep their anger and hatred topped up.

You What I've noticed, When Trump is shown on CNN, He's very Orange, but on Fox, He's a more natural Pink. What's up with that; if the liberal media can't even get the white balance correct, what chance does the facts have?

Comment Re:What happens when it's on something HOT? (Score 1) 202

If you can make the nano-beads just a bit smaller, you could do the same tricks but with VISIBLE LIGHT. Think paints that would really glow at specific frequencies. Shine a blue light on it and it would glow red! Even if expensive, it could be used for specialized inks (think anti-counterfeiting).

That would be a Dichroic filter, that's what's in the reflector in your Dentist's light. It's adjusted to only reflect light frequencies that mimic a 4,500K blackbody.

Comment Re:My dad sent me this weeks ago (Score 1) 202

It would mean that if you have a box of this shit sitting around it would always be several degrees cooler than its surroundings.
If this were real it would be effectively free energy.
Strap this thing some thermo electric device and have it generate infinite energy while sitting out in the sun.

Yes you could, the efficiency would suck due to low deltaT, but it would be a cool science-novelty type thing.

Comment Re:its basically a sun shade that you can see thro (Score 1) 202

Even I can see through this lie. It's really just Maxwell's daemon sorting molecules. Just another BS story on Slashdot that will get hype for a few days and then no product will ever come to market. An obvious clue that even the "inventors" know this is complete bullshit is the claim "All the work is done by the huge temperature difference, about 290C, between the surface of the Earth and that of outer space,". Is anyone buying that crap? 'cause if you don't then it is pretty obvious this can't work.

Abstract: Passive radiative cooling draws heat from surfaces and radiates it into space as infrared radiation to which the atmosphere is transparent. However, the energy density mismatch between solar irradiance and the low infrared radiation flux from a near-ambient-temperature surface require materials that strongly emit thermal energy and barely absorb sunlight. We embedded resonant polar dielectric microspheres randomly in a polymeric matrix, resulting in a metamaterial that is fully transparent to the solar spectrum while having an infrared emissivity greater than 0.93 across the atmospheric window. When backed with silver coating, the metamaterial shows a noon-time radiative cooling power of 93 W/m2 under direct sunshine. More critically, we demonstrated high-throughput, economical roll-to-roll manufacturing of the metamaterial, vital for promoting radiative cooling as a viable energy technology. Scalable-manufactured randomized glass-polymer hybrid metamaterial for daytime radiative cooling

Pretty hard to get your research paper published in the peer-reviewed journal Science, unless it's at least scientifically plausible.

Comment Re:Too good to be true. (Score 1) 202

>Its interesting that they have made the film, yet have not demonstrated it in a practical application. That makes me skeptical as they are relying on performance claims when they shouldn't have to. Why could they not take the film and cover a small structure (like a shed), and simply tell us the resulting cooling effect? And maybe compare against a simple reflective coating

They have a peer-reviewed article published in "Science", other Researcher's have published papers on the same effect using difference materials and the "The Economist" article shows the Researcher's holding a big-ass roll of the stuff, there isn't much to be sceptical of.

Comment Re:Too good to be true. (Score 1) 202

It's not like we're getting rid of any incoming solar radiation. So this kind of heat pump would make the outdoor temperature higher which means it increases the warming that affects glaciers.

1. Glaciers don't melt much because of increased air temperatures, air just doesn't have enough heat to melt much ice.
2. This isn't a "heat pump", it's a radiator, it radiates infrared light at a wavelength the atmosphere doesn't absorb so the heat energy can go directly to outer space.
So yes we are actually "getting rid of any incoming solar radiation."

Comment Re:Cool (Score 3, Insightful) 202

No you couldn't embed them in glass, because the glass beads work by being resonate at a frequency that atmosphere is transparent to. The beads aren’t normal glass, they are transparent infra-red, most glass is rather opaque in infra-red. what you could do is apply it like a window tint, but I suspect it would have a lot of distortion and possibly an opalescent effect.

The film unsilvered is highly transparent to visible light, so the ideal application, would be to apply it to PV solar cells to help cool them and prolong their live span.

Comment Re:The solution is simple. (Score 1) 328

It is perfectly normal for science to yield contradictory results. That's why when you see a study reported saying taking Garcina Cambogia yields astonishing weight loss results you don't immediately run out to the health food store to buy miracle pills. It's absolutely routine for results like this not to stand up. The problem is that journalists are too ignorant of how science works to understand this.

The problem may be the while Garcina Cambogia causes 30% more weight to be lost, 30% more of zero is still zero.

Slashdot Top Deals

"It ain't so much the things we don't know that get us in trouble. It's the things we know that ain't so." -- Artemus Ward aka Charles Farrar Brown

Working...