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Comment Re:First (Score 4, Interesting) 250

Curiously, in my youth in the 60's, we referred to Luna-9 as a "hard landing", and the first "soft landing" was Surveyor 1 three months later. Now, it's clear that the Luna 9 lander really was a soft landing (similar to the landings of the Mars Pathfinder and Spirit/Opportunity rovers) and we were just ragging on the Soviets.

Comment Can go somewhat faster... (Score 4, Interesting) 236

Sending a neutrino beam through the earth will be faster than taking the great-circle route across the surface of the earth.

Of course, one would have to send a ridiculously large number of neutrinos to be sure to have them detected, but that's just an engineering problem.

Comment Re:Put some old news in a new context (Score 1) 237

With fiber optics...I don't think it's very easy. Especially with the new doped fibers that do their own recharging.

It used to be that there had to be transceivers every so often along the fiber, to turn the optical signals back into electronic signals, then generate new laser pulses. The new cables basically build lasers into the fiber, allow it to refresh the signal without going through that process.

Comment Elevation changes make hyperloop almost impossible (Score 3, Informative) 253

Among the many problems with hyperloop is elevation changes. If you're going even 1000 miles per hour, the minimum turning radius to stay less than half a g is 25 miles. There are 4000 ft mountains between LA and SF, and either you have to build a 80 mile long tunnel through them (pretty expensive) or build a viaduct that is 2000 ft high and 100 miles long. Going around the mountains might make more sense, but you're going to end up way out to sea.

Comment Not going to look anything like the simulation... (Score 2) 143

If the mountain is a 2km away the reflection from the mirror is going to be very broad indeed. The sun is a half-degree across, and half-degree times 2km means that the edges of the mirror beam will be about 20 meters wide, nice soft edges and not the harsh ellipse shown. The ends of the ellipse will have edges more like 100 meters wide.

Comment Not the problem... (Score 1) 348

There are thousands of visual effects artists who are, or soon will be, out of work -- who would be happy to model anything for you. Schools today are training thousands more every year.

I think the biggest problem is that people don't want something unique -- they wants something everybody else has.

Think about it -- say you could print your own phone; and it would be unique; custom fit to your hand (say), and really the best possible phone for you. How many would want that, vs. the phone that everybody else has?

Comment Could dark matter be super low-energy neutrinos? (Score 5, Interesting) 151

Back when it was thought that neutrinos were massless, it was impossible to believe that there were huge masses of neutrinos surrounding galaxies, as they would have to travel at the speed of light. But now that we know that neutrinos have mass, maybe they could travel a lot more slowly, slow enough to be captured by a galaxy.

Think about it; there are a huge amount of neutrinos created every microsecond in every star in every galaxy, and they hardly interact with anything. They've been accumulating since the big bang.

What happened to the early photons? Those created as the universe first became transparent initially were very high energy indeed, but as the universe has expanded they've lost energy, to the point that they correspond to a temperature of just 3 degrees kelvin. What happens to neutrinos of a similar vintage?

Comment Re:nothing new here (Score 5, Interesting) 114

I was working at SGI at the time, late 1991. The cheapest way to buy expansion memory was to buy Indigo's and throw out the rest of the computer. SGI was just feeling the first tickles of the commoditization of computer hardware, and was looking for ways to make their components unique (and keep them expensive.)

Comment Like a backward Pixel Qi screen (Score 1) 170

The Pixel Qi LCD screen does exactly this to get high-efficiency color; splitting the RGB colors from the LED backlight to direct it to individual LCD cells. The idea of applying the same ideas to cameras are not new.

A big challenge with this idea, and many others, is that for cameras with variable focal lengths, the light hitting the edge of the sensor might come from almost straight in front (for a long lens); or from an extreme angle (for a wide-angle lens) causing significant issues with this kind of optics-in-front-of-the-sensor camera. For a fixed-focus lens as on a cellphone (like 90% of cameras built today) it's not an issue.

Comment Eerily reminiscent of 3 cable cuts in 2008 (Score 5, Insightful) 166

During a week in 2008, three undersea cables were cut off of Egypt. At the time (and still) the cuts were attributed to ships dragging anchors -- although the fact that there were three cuts so close in time was, and remains, hard to believe.

So, now we see people intentionally cutting a cable. Hmm.

During the second world war, there were teams of saboteurs who were tasked with cutting telephone cables across France, in preference to almost any other target, because it was much easier for the British to intercept radio messages than telephone messages. I can't imagine any other reason for this.

Comment Ambidextrous pitchers? (Score 1) 260

I've never seen or heard of an ambidextrous pitcher. Can you imagine the benefit, though? Switch-hitters are prized for the ability to adapt to a pitcher, but if the pitcher could adapt to the hitter? It'd be amazing.

Now, it might be impossible -- that competitive pitching requires you to make your body significantly asymmetrical -- perhaps the extra mass of the muscles on the other side would slow you down.

I mean, we've had an All-Star pitcher with just one arm! And he pitched a no-hitter in the bigs! Why can't we have an ambidextrous pitcher?

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