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Comment Re:Same here. (Score 1) 110

> There's no way to filter these without going to a strict whitelist (and even that has some chance of a collision error) and unfortunately whitelists aren't suitable for all people.

The way to deal with this on cellphones is to set the default ringtone to "none", and whatever ringtones you prefer to your legitimate contacts. Most telemarketers won't leave a message. The ones that do, I can screen at my own leisure.

Comment Re:Why should I care again? (Score 1) 109

My broker sent money via ACH to my credit union. They sent it four days ago, and it just arrived today. Bitcoin doesn't take weekends or holidays. An hour or less to fully confirm a transaction is like lightning compared to the traditional banking system.

Note that ACH means Automated Clearinghouse i.e. the money is sent via computers. And it still takes up to 4 days.

Comment Re:Wow (Score 0) 104

I never forgot about them, but mined or accumulated steadily from mid-2011 to mid-2016. When the price and my accumulation goal were met, I started selling, which I will do for the next few years, so as not to take a big capital gain all at once. I've already covered my original investment, so it's all profit at this point. I can't predict what the price will do in the future, so it might end up a small or a large gain. We'll see.

Comment Re:What do you want to be ? (Score 0) 104

The service that the Bitcoin Network provides is transfer of value, without restrictions from borders, lack of bank accounts, or high fees, and it does this fairly fast. It's better than bank wire transfers, PayPal, or Western Union in many cases, so some people use it. Bitcoins as value tokens are a necessary part of the Network they are part of, they are the accounting units for transactions. The usefulness of the Network is what gives the coins value, since they are scarce and necessary to perform the Network's function.

Comment Re:What do you want to be ? (Score 1) 104

> Bitcoin is, by all definitions, a fiat currency.

No, that's not what a fiat currency is. "Fiat" is Latin for "let it be so", as in "Fiat Lux" (let there be light) from the Bible. A fiat currency is one that a government authority says is a currency. Commodity money is the kind based on a commodity that has value. Cattle, sea shells, gold, and silver have all been commodity money at one time or another. Usually the most easily traded and widely accepted good ends up that way. Bitcoin is easily traded, being fully electronic, and has other properties good for money (divisibility, durability, scarcity, etc.) and has therefore become a well traded commodity. It is not yet widely accepted aside from the community of merchants and users, so it is not yet a full currency at the level of dollars or euro.

Comment Re:What do you want to be ? (Score 1) 104

There is no such thing as an "official blockchain server". My home PC becomes a bitcoin network node whenever I run the software, and updates my copy of the blockchain when I do so.

Ingenious software is what keeps everyone's copy of the blockchain the same and un-alterable. Solving that problem was the key invention of bitcoin's creator(s).

Comment Re:What do you want to be ? (Score 1) 104

One third of Americans are "unbanked", and higher numbers in less-developed countries. One bout of unemployment or illness, and your credit and bank accounts can be lost for years. Or has happened in my case, Bank of America decided to make the automatic credit card payment twice in one month, for no reason. Fortunately I caught it right away, but I was overdrawn for two days and still had to pay a fee. Someone who doesn't catch it could run up all kinds of fees from bounced checks, and then banks don't want you as a customer.

Comment Re: In addition... (Score 1) 179

> I don't believe the claim that "solar photo-voltaic electricity is now less expensive than grid electricity" as bare fact.

That only applies to utility-scale tracking arrays, not to residential:

Rooftop residential fell to $2.98/Wdc in the 3rd quarter of 2016, while utility tracking came in at $1.21. Tracking systems tilt the panels to follow the Sun, and therefore produce more power than fixed ones on rooftops. So overall, the utility systems are about three times cheaper. Why are they so much less? It is much more efficient for a work crew on level ground than on a sloped roof, and they don't have to pack up their gear and drive to a new location every two dozen panels. You only need one big connection to the utility grid for a solar farm, rather than one for every house, so less wiring/transformers/etc.

At $1.21/W, and assuming the solar farm returns 8% annually and produces for 2000 hours/year, the net cost is $0.0484/kWh, which is competitive with wind and natural gas.

Comment Re:Only in America... (Score 1) 126

> Take for example asteroid mining, how long have we heard about that?

It's been a feature of science fiction since the early days. But making a serious effort at it depends on several things that are more recent:

* The discovery of 15,000 Near Earth asteroids, 90% of which have been found in the last 15 years : The Near Earth group are much easier to reach than the Main Belt asteroids. The more of them you find, the better the chance of some of them being the right composition and right orbit to mine.

* The development of higher power electric propulsion (ion and plasma) and high efficiency solar arrays, in order to power space tugs to bring back asteroid rock to a high Earth orbit. This has also happened over the last 15 years.

* Improvements in space robotics and high-bandwidth communications, which would allow real-time control of a processing plant in high orbit from the ground. This reduces the need for astronauts on site and lowers the cost.

* Growth of a market for the products of asteroid mining. There are now about 1400 active satellites in space : (see page 8) and the number is growing. Without a way to refuel or repair them, they have to be replaced at great cost. Asteroid mining can supply fuel, both for the satellite itself, and to bring them to a repair station. That market is worth billions a year, but again, 15 years ago it was much smaller.

Not surprisingly, now that the pre-conditions exist, people are making serious efforts to develop asteroid mining.

Comment Re: Only in America... (Score 1) 126

The solution to this is reflectors that send additional light into the greenhouses. I'm thinking of something like these linear concentrators:

but instead of focusing the light on a tube to boil water, they focus it on narrow windows in the greenhouse. Since Mars has a similar day length and axial tilt to Earth, the main thing is to increase the amount of light getting into the greenhouse. So the reflectors need to be about 2.5 times the area of the greenhouse floor. I assume most of the greenhouse will be buried under a layer of dirt, because the nights on Mars are *cold* and you want to maintain the greenhouse temperature. A slot at the top of the dirt layer leading to windows would allow the light in, and you can cover the windows at night if needed to retain heat.

The reflectors can be pretty lightweight, because of the low gravity, and relatively low wind loads.

Comment Theory (Score 5, Interesting) 205

My guess is it's a precessing pulsar with an offset magnetic field. Pulsars are well known to produce repeating pulses as their magnetic poles rotate in and out of view. To see the pulses requires they cross our field of view, meaning a specific alignment of the rotation axis vs location of the magnetic pole (which don't have to be the same). If there is a second body near the pulsar, with an orbit offset from the equator, it would cause the rotation axis to precess, just like the Earth's does due to the Moon and Sun. Therefore the alignment of the magnetic pole would move in and out of view, and we only see pulses on the rare occasions they line up just right.

This guess would be defeated if the pulses look nothing like normal ones from pulsars, and confirmed if enough data is collected to detect the orbital motion of a second body.

Comment Re:saturation (Score 1) 30

> is there such a thing as a possible saturation of the PV market?

Yes, in the near term when it supplies all the daytime electricity a grid can handle without becoming unstable. It's not always sunny, so the grid needs enough other power sources to compensate for bad weather. Estimates when this point would be reached with the current grid range around 20-30%. US electric production is between 1 and 2% solar at the moment. I say daytime because power demand is lower at night, and the sun doesn't shine then.

In the long term, with better transmission infrastructure (to overcome local weather), and storage solutions (solar thermal, or batteries), total solar could go higher

> could there be a day in near future (10 years) that there are PV on all the roofs that can handle it?

Only a minority of solar installations are on home rooftops. In the US, the majority are "utility" systems, with many thousands of panels installed at ground level. Most of these today are "tracking systems", that tilt rows of panels to follow the sun, and get more output. Because it's installed at ground level by specialized work crews, and needs fewer support systems per panel, it is 60% cheaper than residential. There is no shortage of open land. Commercial rooftops fall in between residential and utility. For example, WalMart and Target have each installed 300 MW of solar panels on their store roofs. It offsets some of the power used by the stores.

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