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Comment Re:Energy cost [Re:Cost of access is key.] (Score 1) 314

Where are you getting $0.10 per KWH?

The other poster gave some enlightening information on boosters and propellants please give us more details.

I was not addressing boosters or propellants. I was addressing a single point, that "the shear amount of energy" is the problem. There are indeed reasons that getting into orbit is expensive. But the amount of energy, in itself, is not a major cost.

Comment Energy cost [Re:Cost of access is key.] (Score 1) 314

In other words, you can't cheat gravity or the laws of thermodynamics. No one seems to listen, but my initial assessment is that the shear amount of energy required to launch a viable space colony is going to be prohibitive.

Orbital velocity is about 7.8 km/sec, so the energy cost of getting into orbit is 1/2mv^2 = 30 MJ/kg, or about 8.5 kW-hr/kg. At an energy cost of 10 cents per kilowatt hour, that would be an energy cost slightly under a dollar a kilogram.

Energy cost, in and of itself, is not the problem.

Comment Polynesian expansion across the Pacific (Score 2) 314

And the Polynesian Islands were populated before Europe had boats.

No, they weren't.

"Polynesian ancestors settled in Samoa around 800 BC, colonized the central Society Islands between AD 1025 and 1120 and dispersed to New Zealand, Hawaii and Rapa Nui and other locations between AD 1190 and 1290."

Your Eurocentric view is blocking you from seeing that explorers predate Columbus and made ocean crossings long before

Yes, that part is right.

Comment Cost of access is key. (Score 2) 314

Right now, the barrier to increasing use of space is the cost of launch. It's indeed true that, with launch costs at their current levels, utilization of space resources isn't likely to be commercially viable (at least, not for applications other than the ones already being done, such as observation and communication.)
The critical question is, can the cost of getting to space be reduced? And if so, by how much?

Comment Re:Space Ship One? (Score 1) 121

Oops, good point, that should have been mentioned indeed. In my defense, I'll say that this was a quote I pulled from the Geekwire article (which has since, to their credit, been revised)
SpaceShipOne re-used everything except the actual rocket engine (that is, the combustion chamber and ablative nozzle) which was replaced for each flight (much like a model rocket, now that I think of it).

Submission + - Blue Origin "New Shepherd" makes it to space... and back again

Geoffrey.landis writes: Blue Origin's "New Shepherd" suborbital vehicle made its first flight into space (defined as 100 km altitude)... and successfully landed both the capsule (by parachute) and the booster rocket (vertical landing under rocket power). This is the first time that a vehicle has made it into space and had all components fully recovered for reuse since the NASA flights of the X-15 in the 1960s.
Check out the videos at various places on the web

Comment Yes, he was arrested [Re:That won't last long...] (Score 5, Informative) 788

The school certainly overreacted, but...

1) the kid was not arrested

Yes, he was. He was taken away from the school by the police in handcuffs. That's an arrest.

I think what you meant to say was, the kid was not charged. That's correct. He was arrested, but released without charges.

Comment Citation needed. (Score 2) 108

Do you have a source for this? I do like the fact that they are trying to close the loophole before it is implemented but I can find little to back up your claim.

You might try to do your own homework at, where everything is published for all to see.

No, when you cite an alleged fact, you should give the citation.

Presumably you have a citation, if it's a real fact and not something you made up. When you don't provide it, a pretty good guess is that either
(1) it's something you just made up, and hence I shouldn't waste my time to try to track the non-existent fact down with an internet search, or
(2) it was too much trouble for you to do the internet search to find-- and if it was too hard for you to find, being sarcastic about why I won't spend my time finding it is completely hypocritical.

Executive summary: when you cite a fact, it is your burden of proof to provide the citation.

Comment Re:Summary missing information (Score 3, Informative) 120

And the magnetic field stopped why?

Mars, being half the diameter of Earth, has a higher surface to volume ratio. Thus, it cooled faster. Presumably the liquid core froze, or at least, enough of it froze to stop the dynamo of molten metal that creates the magnetic field

Comment Geheime Staatspolizei [Re:drones] (Score 2, Insightful) 318

Wrong? Not really, no.

The U.S, Constitution-- heard of it?-- demands that the government cannot deprive citizens of life without due process of law.

It is possible that the people hit by the drone strikes have had some legal process applied to who gets targeted... but due to the secrecy, we don't know that. From all the evidence I can see, the "due process" is that one CIA guy says "I think this person should be on the list."

When I was a kid, you could tell which countries were dictatorships: those were the ones who had secret courts and secret police with secret powers with no limits and no oversight. In German, there is even a word for such secret police-- "Geheime Staatspolizei", literally "secret state police." More commonly called the Gestapo.

Now I live in a country with secret courts and secret police. I don't like it.

What is that due process, how is it implemented, and by whom? Without that question answered, we live in a dictatorship, and simply don't know it.

Comment Re:drones (Score 4, Informative) 318

No US citizen was murdered by a drone, they were killed, legally. The law of war permits that. When you fight with the enemy in an armed conflict against the US you are part of the enemy and can be killed just like any other enemy combatant. That is what those US citizens had done, and it cost them.


Some of the Americans killed were fighting with the enemy. "Some" is not the same as "all".

Comment Links (Score 2) 318

The article linked is actually an editorial in the New York Times:

Links to the actual case, from the Associated Press, on the Boston Globe site:
"American can't sue FBI over abuse claims, federal appeals court says",

Link to the decision:

Mommy, what happens to your files when you die?