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Comment Re:The Future is Yours! Only 10 small payments of (Score 1) 77

Good points. But, hey, 150B USD have been spent on the pretty much pointless ISS. Surely humanity can afford another 50B or 100B or so to keep the handful of inhabitants healthier. I'm not against man in space BTW, but I think the Skylab approach of a lab that was staffed for a few months every now and then to perform experiments that actually had some merit would be a lot more cost effective.

Comment Re:Cool (Score 1) 77

Yes, although a bolas might be difficult to spin up? I'm a lousy physicist, but I think you need to apply exactly equal (and opposite?) accelerations to both the weight and counterweight lest the center of mass and thus the whole object start to wander off? Also, I think accelerating and decelerating a bolas-like Mars mission might be tricky?

Comment Re:Cool (Score 1) 77

A centrifuge would (and probably will) work fine. Problem is that it has to be BIG. Otherwise your astronauts will be wandering around with different parts of their body subjected to different accelerations. e.g. If you spin up a 2 meter tube, a 2 meter tall astronaut "standing" upright will have his/her feet and head pulled in opposite directions by whatever "weight" you choose to configure. Probably not a good idea -- at least not long term.

Comment Re:This is old news (Score 1) 146

God only knows what motivates the far Right. I think many of them don't like renewables and therefore dislike Solar City. And in that specific case, they may have a valid point. The SC operation seems kind of shady to me. SC gets the money. The homeowner gets probably expensive electricity and all the risk.

Why they dislike Tesla, Space-X, and the battery factory escapes me. Private businesses competing with other private businesses. In the case of Space-X, purportedly doing a better job than NASA. What's not to like unless they like me think Musk is ... ahem ... less than honest ... at times in his claims? It's not like those folks can possibly have functioning BS filters.

Comment Re:Kalman filter (Score 2) 110

"How in hell did they test their Kalman filter to allow such bad data to reach the decision logic? (I assume they used one.)"

1) A Kalman Filter probably is not really appropriate here because the parachute has just been deployed and you wouldn't have state statistics available to filter the input data. Doesn't mean they didn't use one with ad hoc statistics. That's not as uncommon as perhaps it should be.

2) Presumably the IMU is expected to tell you the probe has run into the planet (i.e. landed) and it's time to get rid of the 'chute before it lands on your probe and also time to shut down the thrusters lest they bounce the probe across the landscape or flip it upside down. Depending on how often the IMU is read out during landing, a full second of bad data may be pretty convincingly NOT noise.

Not that I know anything about landing Mars probes.

Comment Re:Not worth the materials its made of (Score 1) 117

"These batteries are not rechargable and a complete waste of time and effort."

Of course they are rechargeable. They seem to be quite similar to NiFe Edison Cells which are used in a few applications because of their virtues -- long life and tolerance of overcharging and deep discharge. The Edison cells have some problems which discourage them from wider use including inefficiency and, IIRC, high self discharge rate.

Comment Re:So? (Score 3, Funny) 117

"The electrodes are prepared with ammonium fluoride, argon, platinum/calomel, potassium hydroxide, and hydrochloric acid"

"When scraps of steel and brass are anodized using a common household chemical and residential electrical current, the researchers found that the metal surfaces are restructured into nanometer-sized networks of metal oxide that can store and release energy when reacting with a water-based liquid electrolyte."

Common household chemical? Just checked. I'm flat out of Aluminum Fluoride and Platinum/Calomel. The Argon tank is empty too. I do, as it happens, I do have a bit of HCl in the garage. Can I substitute peanut butter and laundry detergent for the chemicals the experimenters used?

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