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Comment Re:Cause rockets are the way (Score 2) 266

Yes. Like every other new complex technology it takes time to find all the problems and fix them. Early cars had a tendancy to catch fire and break down. Steam engines would explode. Airplanes would crash. Will rockets ever be as safe as airplanes probably not on a per launch bases but on a miles traveled perdeath they will be safer than cars are today.

Comment Re:Why? (Score 3, Insightful) 59

Rocket engines are incredibly powerful for their mass. Other engines are much more complex and have higher mass to thrust ratios. The tanks for fuel are very low mass compared to the fuel they contain. Scram jets require a booster system of some type to get them supersonic. Once super sonic they work until they run out of atmosphere and then the orbital system needs rockets to get into space. So in order to reduce the mass of oxidizer they add a subsonic to sonic booster system and then to operate in space they add a rocket. Seems much simpler and lower cost to just add bigger tanks to the rocket and forget all the other stuff.

Comment Why? (Score 5, Insightful) 59

I just do not see why people keep trying to eliminate the weight of oxidizer and propellent. IE scram jets or space elevators when the cost of propellants is so small. The propellent cost for a Falcon 9 launch is only $250,000. The Falcon 9 can put 50,000 lbs of cargo in low earth orbit that's just $5 per pound for propellent. Propellent does not matter. What matters is the cost of the vehicle. We need 100% spacecraft reusability for 1,000's of launches to get the cost of space travel down. Space X is working towards that goal. The current engines that use Kerosene will wear out rather quickly because the engines need to run with excess oxidizer to prevent them from being fouled by carbon build up. The oxidizer causes the engine to rust out(titanium rust). The new Space X engine uses liquid methane fuel. It can be run with a more perfect oxidizer/ fuel ratio and eliminate the corrosion problem so much longer life.

Comment Re:Robots at the wrong side of economics (Score 1) 1052

Price is the means used to allocate resources in a market economy. When prices of a product or service is high relative to others it signals the economy to move productive capacity from a low priced meaning highly surved product or service to the one in higher demand. This is why market economys kick the shit out of command economys. Price provides the feedback to tune the economy to the highest productivity possible. The "greedy bastards" who serve the market best and fastest are rewarded the most. When people are free to choose what they buy and what they make the people who satisfy the wants and needs the best make the most. The only people in a market economy who can "gouge" you on prices are those that the government protect with copyright, patents and regulation that inhibits entry into the market. I am always amused when i hear people who say the government needs to stop those durty profiteers from gouging them when it is already the government that enables them. It shows their entire lack of understanding about how our economy works. A business cannot force you to do anything only the government can. All a business does is offer you stuff you want and/or need at a competative price. The government has a place in controling monopolies however a company useually does not become a monopoly without serving customers well unless it has government backing.

Comment Re:But... (Score 4, Interesting) 193

Unfortunately you are traveling faster than escape velocity. Therefore you CANNOT "enter orbit". The planet will only deflect your path. The laser idea is just that an idea. Interesting but totally impractical and unworkable. Better to put a liquid salt thorium nuclear reactor and ion drives onboard the space craft. Or use an EM massless drive if it turns out to be real and not an experimental error. The light weight thorium reactor could use both ion drive for long haul low acceleration to conserve reaction mass and for a burst of high acceleration you could use the thermal output of the reactor to heat reaction mass and expel it directly. Interesting idea for a hybrid nuclear rocket system.

Comment Considerate adds What a concept (Score 1) 287

Absolutely Right! I do not mind adds served considerately. On the side or below. When an ad pops up over my screen I close the window and go somewhere else. Most content is not worth being annoyed over. If the publishers want people to look at their pages impose some limits on what the advertisers can do. I would like to see a web browser designed so popups and pop overs are not possible and a filter that makes all links to sites that do not impose considerate advertising standards just disappear. In other words every link on a page is previewed if it is found to contain crappy adds and maybe even paywalls that link is either removed or replaced with a warning saying bad ad Pay wall etc so you do not even have to click it to find out. When traffic to those sites dry up they will begin to act better.

Comment If they only considered the customer (Score 1) 581

At one time an upgrade was an upgrade. Things worked better, faster, simpler and you got some nifty new features. It was more stable and secure. Now every new upgrade seems to come with many undesirable side effects. Interfaces change. Settings move or are eliminated. Productivity drops. Stuff that used to work does not. After a couple of times having updates/upgrades break your system you turn the updates off. If Microsoft had done a better job of crafting updates to not break or change settings so the system remained stable as far as the user was concerned then people would welcome the changes. I have still not forgiven Microsoft for the switch to the damned Ribbon interface in their office products.

Comment Comprehensible User Interface (Score 1) 508

The user interface on computers, tablets and phones have continued to "evolve" beyond comprehensibility. Constantly changing the interface does not make it better only different and in many ways worse. Hiding menus and requiring several different ways to access settings makes for a very poor user experience. The Apple clean look, Androids and windows attempt to replicate it just shows that the programmers know nothing about human factors and interface design. It should be obvious how to do something not hidden. Searching for how to open a menu is not fun its a pain in the ass. It should be easy to turn off annoying garbage functions not take 15 minutes of internet searching to learn the secret handshake of the month.

Comment Fuel cost is not the issue its the rocket (Score 2) 151

Fuel is a small cost of a space launch. Only about $250,000 per low earth orbit launch is fuel. The big cost of space flight is the throw away rockets. Going to extreme measures to save fuel is not a wise use of resources. With the boost capability of the Falcon 9 it would take maybe 100 flights to carry the amount of fuel and resources needed for a flight to Mars and back. Assuming 100% reusability the cost to carry the fuel to orbit is only $25million. Developing and building a refueling station on the moon and manning it would probably cost many billions of dollars. Spending billions to save millions does not make much sense. The thing that will make space travel cost reasonable is getting to that 100% reusability and long operating life. A rocket with 120 flights to orbit would only have 40 hours of run time on it. Current Jet engines can run for thousands of hours between rebuilds. The Air frame can go much longer than that. Once we get rockets and engines with those same types of run times and perfect vertical return landings flying to space will not cost much more than the fuel and it is cheap.

Comment Body Armor and Fire only after fired upon (Score 1) 712

2 Simple rule changes. All officers must wear body armor. No officer may initiate force greater than used against them. In other words. You may not touch someone until touched. You may not hit someone unless hit. You may not fire on someone unless fired upon. There were 126 officers killed in 2014 and police killed 1107 people. So who is really at risk here. We the people suffer much more harm from the cops than the cops do from us. A significant number of the police deaths could have been prevented if they had worn body armor. Proper armor would reduce the need to "protect themselves" by killing a kid with a pellet gun. Yes these rules would make policing more difficult. Instead of killing people shoot/spray/dust them with tracking aids. Then chase them slowly relentlessly until they give up or become aggressive and force must be used. The idea is to train the cops to talk people into giving up peacefully instead of needing to resort to violence. If the cops knew they could not push people around the job would not appeal to the wrong kind of people. Probably not a workable idea but it would be nice to try.

Comment Remarkable Number? How many is a remarkable number (Score 1) 367

It's not remarkable at all. People believe professional wrestling is real, homeopathy is real, ghosts, devils and gods are real. So what makes belief in a well made movie depicting mostly good science less believable than all that other hogwash. People are programmed to believe. Being skeptical is hard and a vastly smaller number of people ever question anything they are told or shown even if it not presented as the truth.

Comment Strength of tape and plastic sheet (Score 3, Interesting) 242

Spoilers below: I agree liked the movie. Good science on the orbital mechanics and many of the issues. The ending was far fetched. The small amount of mass expelled by blowing the hatch would have little effect on the speed of the ship.The risk of unintended irreparable damage would be massive. Why not use attitude thrusters or just turn the ship around and use the main engine sounded like they had plenty of fuel. I would think they would have considered needing to make course adjustments before hand and stopped the habitat rotation so attitude control was easy. I was disappointed when he used plastic sheet and duct tape to replace the airlock that blew off the habitat. No way a thin sheet of plastic is going to hold 12psi needed to make the habitat habitable over that 8 ft diameter hole. Similar issue with the bubble taped to the rover for storing supplies. Might be possible with some kevlar fiber reinforced material but not the clear poly sheet he appears to use. Sealing the plastic to the habitat and rover adequately would be just about impossible. Still liked the movie and may read the book.

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