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Comment Re:Missing Option: (Score 1) 139

Yeah... that meme is getting old. Some of us are married over 20 years now. I started reading /. in 2000. Lost my older UID when I left for a few months, came back, but couldn't recover my password because I no longer worked at the company that owned the email address I registered with. UID name I'm using dates back to the mid-'80s. Some of us have been around a while.

Trust me dude. You might have it better... My wife is definitely not a morning person. Nothing like waking to the sound of your wife shouting at the children to get your day started right...

Comment Re:2 trillion tons (Score 1) 139

You start with one 10 ton/day reactor. Next quarter you build a 50 ton/day reactor. Then you build a 250 ton/day reactor. Then you build a 1000 ton per day reactor. Once you hit maximum scale that's economical, you reproduce the reactor and work on efficiency. Most petroleum refineries are not one big giant crude oil distillation unit. They're many systems working in parallel. And there's more than one refinery...

Comment Re:Great! We can take it out of the ground (Score 1) 139

Your math is off. If there is demand for 100 barrels of oil for use as fuel, we will pull 100 barrels out of the ground and burn it. If we substitute 10 barrels of oil from recycled plastics, then we only pull 90 barrels of oil out of the ground. In both cases, we still burn the same 100 barrels of oil. The plastic existed already -- the energy required to pull the oil out of the ground and process the constituents into the chemicals pre-cursors for the plastic had already been spent. There's only a small net increase in CO2 production due to losses from reprocessing the plastic (again), which may be offset by not producing CO2 when extracting the oil from the ground and transporting the crude which it replaced.

Comment Re:Pointless pork for manned spaceflight (Score 1) 65

It takes more than a year to get the robot to the surface with it's instruments. These robotic probes are often a decade in planning, manufacture, testing, integration and launch. In fact, the robotic probe will likely be sent on a slower, less energetic path; so, it will take longer to get there. That's not the point. In the same amount of time on the surface, the human can accomplish considerably more.

Comment Re:Pointless pork for manned spaceflight (Score 4, Insightful) 65

While I don't have a high opinion of the SLS stack or of Congressional pork... One of the problems NASA is faced with is justifying their existence, which in the public eye (i.e. our representatives in Congress) has to include some form of manned spaceflight. This while not having the funding wherewithal (as provided by the same Congressional representatives) to complete a flagship manned planetary or lunar exploration program.

You can't completely discount manned spaceflight as having absolutely no scientific value; because, there is scientific and technical value in performing a manned mission to an asteroid parked in orbit. There's a quote that goes something like: "A geologist with a rock hammer could learn more in an hour than the robotic probe learned in a year." It's a gross oversimplification but there's some validity to it. By putting people on the site, we can learn quite a bit about the makeup and structure of the sample asteroid that might not be possible with a single pre-designed robotic probe, regardless of how well designed. A human in-situ can make observations and connections based on experience that a robot might not be equipped to make. Said human could then make decisions based on that information, which might be different than decisions made by a remote operator.

In addition, in the process of designing and flying the vehicle we gain valuable technical information necessary to support various human. We get improved engine designs for vehicles, human or robotic. We get better life-support designs which can be applicable to terrestrial applications as well as space. We get better harsh environment suits. We test the ability of our systems to support "long-endurance" human spaceflight outside the cozy protected orbit ISS resides in.

Now, if your argument is simply that we shouldn't be putting humans into space at all, as it's too dangerous and/or expensive... I don't know that I have a counter argument that you'll find acceptable. Sure, we can do some things more cheaply using robots and automation. That's true with many human endeavors. McDonalds is working on automating food production in their restaurants, for example. Agriculture can be largely automated. Manufacturing can be automated. Art can be automated. We use human labor because humans are cheap(-er) than using machines or humans introduce artistic / cultural variation, or humans can make observations and connections based on experience that machines cannot (yet) make, or we just have a surplus of humans looking for something to do...

Sending people to space is expensive because of the energy cost (boost out of the gravity well) and life-support cost. There's no getting around the energy required to boost out of the gravity well; but, we can improve the vehicle and drive costs down. Life support costs we can reduce through infrastructure improvements. If we're ever to have any kind of presence in space, we have to start somewhere; and, that's going to require putting humans into space to obtain experience that cannot be obtained remotely via robotic telepresence. If we're going to reduce the cost, we have to build infrastructure, which is largely going to require some human supervision. We're going to go there eventually; the root technology is available now.

Comment Re:"Held together lightly" (Score 1) 65

Not a lot. However, they've been in free fall around the Sun for as much as 4.5B years. The pile of rubble will pick up the odd grain of sand, chunk of ice or small piece of gravel every now and then as it orbits; and, it will stick together and grow. Or it will fly apart as was evidenced by Hubble sees asteroid breakup

Comment Power? (Score 1) 79

And how will you power said cube sat and chip sats? You're way out at Jupiter, where sunlight is a bit scarce and you're in orbit around the planet, meaning what sunlight you have is not available for the entire orbit as you pass into eclipse. Oh, and you have to transmit the data with more than a few milliwatts of RF; you're way out at Jupiter, ~350M miles is close approach. It works in Earth's orbit because sunlight is much more intense and you only have to communicate over a few hundred miles distance.

Comment Re:Pricing of other bikes is off (Score 1) 85

You're absolutely right; but, people who buy Wal-mart bikes either aren't bike people; or, know they're getting a throw-away and live with it. A $79 bike will be heavy, poorly built, uncomfortable (because one size fits all, right?), the cheap derailleurs will not work reliably, the free hub and cassette will fail fairly early on. To add another price-point, you can pick up a low end bike from a local bike shop for about $450.

Comment Re:Next up: We need a centrifuge in orbit! (Score 1) 76

I'm not forgetting China. In fact, I believe China and Russia are negotiating an agreement to cooperate on future space ventures. This should put the U.S. on notice that it's about to be outdone; but, I fear Congress is not capable of looking more than 2 to 4 years into the future and is concentrating too much on local politics.

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