You can calculate a lot from this information. From the rotation period and velocity we get a radius of 57,000 km, and an equatorial rotation velocity of 12.5 km/s.

From the mass we get a surface gravity of 389.6 m/s^2 (about 40 g's), but the centrifugal acceleration from rotation is -2.74 m/s^2. Thus the body would not be flattened as much as Jupiter. The density is about 24,500 kg/m^3, higher than Osmium. Iron at the core of a planet is quite compressible, so for a large body such as this, it can give such a high density.

One reason is fear. People who depend on a paycheck denominated in today's currency are afraid their pay and all their assets will be devalued if bitcoin replaces that currency. It's an irrational fear. There will be just as many opportunities to earn bitcoin as the alternatives it replaces. Things that have value (like houses) will still have value in a bitcoin economy.

The other thing is resistance to change. Lots of people don't like change.

You are confusing a data entry in a ledger (bitcoin transactions in the Block Chain), and the Bitcoin Network, which enables efficient delivery of money from one place to another. The latter has value for the service it provides, and from the software, hardware, and user base it includes. Those don't need backing by anything else.

The 60,000+ merchants who accept bitcoin today would disagree. In fact, data from the Silk Road indictment and the bitcoin Block Chain show drugs were never more than 4% of total transactions. It was way more than 4% of *news stories*, because a drug marketplace grabs more eyeballs than paying for socks and sheets, or web hosting, but that's the mainstream media for you.

The money they raised was in dollars, and will stay in dollars until fall. So the students will get $100 worth of bitcoins at the time they get it, although we don't know the number of BTC that will be yet.

It's solving the "Byzantine Generals" problem ( https://research.microsoft.com... ), which in simple terms is how to reach consensus without trust. In the context of a payment network like Bitcoin, the consensus to be reached is which transactions have occurred, and therefore what account balance each user has. Prior to the Bitcoin network, the only known method was a trusted third party, such as a bank, who keeps a central ledger of transactions and balances. The problem with a middleman is they can extract excessive fees, or arbitrarily decide not do business with you.

Bitcoin solves the problem using a distributed public ledger, with a "proof of work" function and chained hashes for blocks of transactions. The distributed ledger means everyone has a copy, and can independently verify the history of transactions. The proof of work generates consensus by adopting the longest chain of blocks as the true history. It had the most work put into generating it. Chained hashes use the hash of the previous block as part of the data for the next block (along with new transactions). So any change to past data is detectable.

Since the software is open source, and anyone can create private keys and associated account addresses for themselves, nobody can tell you they won't open a checking account or give you a credit card. Finding block hashes and collecting the rewards and transaction fees is competitive, so fees are set by the market, and not by an oligarchic entity.

The Block Chain technology creates trusted records for transaction data in an untrustworthy environment. But since you can hash any kind of data whatsoever, not just financial transactions, you can keep trusted records for any kind of data. This has usefulness far beyond bitcoin itself, although few of those uses have been developed yet.

> So, how does this work?

Internally, the bitcoin software and the Block Chain ledger track integer numbers of "satoshi", the smallest unit in the system. One bitcoin is equal to 100 million satoshi, in the same way USD $1 million is equal to 100 million pennies. Back when one bitcoin was worth a few dollars, it was convenient to use that unit. Now the developers are considering jumping to a coin unit that is 100 satoshi (a millionth of a bitcoin), since dealing with fractions appears to be hard for people.

> I'd thought it was an atomic unit,

I'm afraid that's a common, but wrong impression. Satoshi are the atomic unit, i.e. the smallest unit tracked in the software and ledger.

> How do you spend a fraction of a bitcoin?

Type in the amount into the wallet software of your choice. Here, watch transactions go by: https://blockchain.info/

> Are there bitpennies?

Not with that name. Most people use bitcoins (BTC), millibitcoins (mBTC), microbitcoins (uBTC) and satoshi as units, depending on what they are dealing with.

Stormtrooper replies: "These are not the cast we are looking for"

It's much worse than that. You know all that unseen mass holding the Galaxy together? It's gone over to the Dark Matter side of the gravitational force.

Flushed Away?

The right approach to this is to cover parking spots for electric cars with solar panels. That gives you enough surface area to get a reasonable charge. Since electric cars are still fairly rare, you only need a few such spots in a shopping center or business park.

You might want to check and see if there is a "Makerspace" (community workshop) in your area. The one's I'm familiar with have better machines than home users can afford, because the cost is split up amongst multiple people. Some of them are for-profit ventures, others are non-profit membership type places.

> I can't imagine I would need/want to 3D print something that often that having my own 3D printer would make sense.

What will likely happen is home centers/hardware stores, or independent businesses, will have pro-grade 3D printers that you can go to and print stuff out when you need it, like the Office Depot/Max/Staples stores have a copy center in the back with pro-grade Xerox machines.

> Everything else is wood, glass, polished chrome or brass, electronics, plant or animal based cloth/textiles

Hence why makerspaces are becoming popular, and why I am working on self-expanding production (where you make parts for more machines to expand your capabilities). A home 3D printer simply won't satisfy most needs that people have. A makerspace (community workshop) can afford to have multiple computer-controlled machines (CNC Router, laser, etc.) that can work in different materials and different sizes. For example, a 4x8 foot router table can cut up an entire sheet of plywood to make self-assembled furniture. Such a device is reasonable for a community shop, but unreasonable for most home users.

The next step will be a "MakerNet". A single community workshop may not have all the machines to make a desired product. So when you want something, software will divide up the product design files and send them out to multiple locations, who between them can do all the various parts.

If you are referring to the game currency, it's not secure against counterfeiting or inflation (Hasbro can print more whenever they want).

If you are referring to fiat currencies, they are in fact government or central bank monopolies, but also not secure against counterfeiting or inflation.