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Comment: The incredible shrinking nucleus (Score 1) 4

Well, I guess that takes a bit of the sting out of the missed impact opportunity.

If the nucleus really had been 50km in diameter (original estimated maximum), and if it had hit Mars, it would've significantly increased Mars' atmosphere with one blow. I'll confess that I was a bit disappointed when we realized that wasn't going to happen.

A comet this small would still have made an impressive boom, but it would have been perhaps a bit less world-changing.

Comment: Highway analogy (Score 1) 101

I'd recommend against pushing that highway analogy. It makes it too easy for them to come back with:

"You don't get to drive 150mph on a highway designed for 70mph."

"We need to make sure overweight trucks don't destroy the road surface for the rest of our drivers."

"If everyone drove as much as you do, the roads would be so jammed that nobody would be able to get anywhere."

Each of these points is flawed, but the analogy you posed doesn't do much to help that.

Comment: "Troll"? Really? (Score 1) 77

by jeffb (2.718) (#48170141) Attached to: An Air Traffic Control System For Drones

Apparently I should've leaned less on snark in my original comment.

By mandating central control, you're making so many assumptions -- the central controller is correct, the central controller scales successfully to the maximum traffic level, there is reliable communication at all times between the central controller and every autonomous agent, every autonomous agent correctly reports its position and status to the central controller, every autonomous agent responds correctly to direction from the central controller, and those are just off the top of my head.

I think the odds of getting every one of those elements right are vanishingly small, compared to "each autonomous agent implements collision and congestion avoidance to the best of its ability". This isn't my field, so I may be far, far off base, but I'm honestly not trying to troll here...

Comment: Where have I seen this pattern before? (Score 0) 77

by jeffb (2.718) (#48167919) Attached to: An Air Traffic Control System For Drones

Autonomous individuals sometimes do bad things or get into conflicts. The solution is a central, controlling authority that knows what's best for them. A central, controlling authority can always work things out better than autonomous individuals, because it has all information and always knows the best way to act on it.

Wow, why hasn't anyone thought of this before?

Comment: Re:As well they should. (Score 1) 243

No, I'm really not; I'm looking at graphs from references and tutorials, some at a pretty introductory level, some at a more advanced level. None of them are from sites trying to market anything -- unless you're implying that Big Grow Lamp has infiltrated and corrupted biology texts stretching back decades.

You raise interesting points (in other subthreads here) about green light penetrating further into a growing plant, and I'll certainly grant that the absorption curves don't reach zero in the yellow-green range.

I'm not in a position to watch or listen to a video; can you link to any other information about the "ZERO LIGHT growing technology" you mention?

Comment: Re:As well they should. (Score 2) 243

Also, green light is great for plants. Don't let old science fool you. Why do you think an HPS lamp works so well despite about 80% of its visible light output being green and yellow?

When I GIS "photosynthesis spectrum", I see a million different curves, but they all peak in red and violet-through-blue-green. Even if you don't look at emission and absorption curves, just look at a plant. Its leaves are green. That means that it's reflecting more green light relative to other colors. That should be a clue that green light isn't the most efficient choice for feeding plants. (It's not conclusive, of course; nature's paths aren't always optimized for efficiency.)

Why do HPS lamps work so well? I don't know, but here are some possibilities:

They're many times more efficient than incandescent grow lamps, so you get more usable light per watt even if its spectrum isn't ideal.

HPS grow lamps are tweaked to produce more red light.

HPS lamps put out a huge total radiant flux, so they're just brighter than alternatives, in both useful and wasteful wavelengths.

Can you provide some supporting evidence that "green light is great for plants", when it's near the bottom of the photosynthetic absorption spectrum?

Comment: Re: I have seen some malware trying to infect my M (Score 1) 172

by jeffb (2.718) (#48045997) Attached to: New OS X Backdoor Malware Roping Macs Into Botnet

And this differs from the average user of every other consumer or business platform in what way, again? I mean, average Windows or Android users may not "think their machine is impervious to viruses", but they seem to "see no issue in" downloading random "music" or "videos" or "software" from even the skankiest sources.

It used to be that a combination of perhaps-somewhat-better security design and low platform population kept Mac users relatively safe even in the face of "average" ignorance and complacency. They're probably still safer than they would be on Windows (perhaps even Android), because they're still a bit of a niche market, but the margin continues to narrow.

Comment: I wonder what a government node could do. (Score 4, Interesting) 85

by jeffb (2.718) (#48031815) Attached to: Hong Kong Protesters Use Mesh Networks To Organize

Mesh networking, peer-to-peer, power to the decentralized people -- it all sounds great. But some of those people will still be on the side of the government. I wonder how much information one mesh node could accumulate to incriminate other participants? How many of "the people" will be willing to participate in an uprising like this if they know that a government stooge is likely no more than two or three hops away?

Comment: Fine. Legislate for externalities. (Score 4, Insightful) 488

by jeffb (2.718) (#48024011) Attached to: Energy Utilities Trying To Stifle Growth of Solar Power

There's a long tradition of regulating electrical utilities -- their new-plant construction, their service build-out, and most especially their rates. If connecting single-household solar installations and buying back power from them is imposing an undue burden, and they can prove this, adjust the tariffs accordingly.

But you shouldn't quash an entire emerging industry just to protect an old and established one. Unfortunately, that seems to be one of the main duties of legislatures.

Comment: Psst. It's 3D printing for LIFE EXTENSION. (Score 1) 26

by jeffb (2.718) (#47999933) Attached to: 3D Bioprinter Creates "Living Bandage" Skin Grafts For Burn Victims

I repeat. It's 3D PRINTING FOR LIFE EXTENSION -- specifically, preserving the life of patients who would otherwise face a fairly quick (and extremely painful) death.

I'm listening for that faint sound of a certain Fark refugee's skull rupturing in the distance.

Machines certainly can solve problems, store information, correlate, and play games -- but not with pleasure. -- Leo Rosten