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Comment delta-V, gravity, Lagrange points, time (Score 1) 892

Space combat, to the extent that weapons would need to be brought within relatively short distance to a target and positioned, might be somewhat like combat between the great sailing ships. Instead of the wind, a ship would need to work with -- and against -- gravity. Changing orbits requires a lot of energy to apply well calibrated force in a given direction. This speeds up the ship, slows it down, etc. It takes lots more energy to change an orbit out of the plane of the Solar ecliptic. We typically refer to these energy requirements in terms of "delta-V" which means just what you think it does. Knowing how to wisely spend the energy on board to bring your ship into firing position would be a fine art of combat in space. Skillful energy management means knowing how to navigate by using single and multi-body gravity to your advantage because that can give you essential free delta-V (e.g., like the various "slingshot" maneuvers deep spacecraft now use to get to the outer planets). The Lagrange points around every massive body (there are 5) are points of gravitational equilibrium. Something positioned there doesn't move (much) relative to the nearby mass bodies. L points can also be orbited in various ways. The lowest energy trajectories in the Solar System are between Lagrange points -- but that can take a long time. Fast, more direct routes take much more energy. How long can you accelerate? How long should you coast? Interplanetary navigation is extremely hard and not many people in the world today can do it well. Combat would be a chess game of picking trajectories, changes in orbits, keeping options open as long as possible so not to tip your hand to the enemy, and feints to mislead them about your intentions. Once committed, it is likely that many engagements would be very high speed passes. So fast that human reaction time would be far too slow. That means the ballet of space combat would be worked out well in advance and handled in real-time by computers, along with any contingent actions requiring speed. Another key point is that with the distance between ships in deep space necessarily come light-time delays. Two ships separated by a distance on par with Earth and Jupiter would experience a one-way light time delay of around 9 hours. That means they are seeing what the enemy did 9 hours ago! So predicting an enemy's moves is very important -- and very hard. Firing ballistic kinetic weapons at a distance would be EXTREMELY problematic, although if you could predict where a ship would be a kinetic weapon would do massive damage due to the relative velocity involved. Energy weapons might very well deplete your total energy for maneuvering, so that is another tradeoff to manage. So I agree with other posters -- space combat would be mostly very boring for everyone apart from the planning of the engagement and the actual firing of weapons -- possibly being on the receiving end of weapon effects. Great topic!

Comment Tech been around long time (Score 1) 161

This kind of thing has been around a long time in the diplomatic community. I'm familiar with one company in California that provides these in various styles to governments world-wide. The briefcases carried by most high profile State Dept. employees are armored and they are taught to cover their torso with them if a shooting incident unfolds. Clipboards are a great idea. Maybe we should give them also to teachers, convenience store clerks, etc. I'll wage that some OWS protestors in Oakland and elsewhere could have used the armor too! I say armor power-ups for everyone.

Comment Just do it (Score 2) 544

If this happened to me I would make a big scene, refuse to turn over the camera and also charge anyone who tried to take away my camera with assault and theft. If the mall guards detained me I would arrest them for false imprisonment. People cannot go like sheep. You must fight back with barred teeth.

Comment Spider Silk from Transgenic Goats (Score 1) 49

"After injecting spider genes into a goat, a silk-like material, dubbed BioSteel®, is extracted from the goat's milk. Because of its compatibility with the human body, BioSteel appears to have some remarkable real-life applications (artificial limbs, tendons and ligaments). It is stronger than steel with a breaking strength of 300,000 pounds per square inch."

This research was being done by a company called "Nexia Technologies", which unfortunately went bankrupt. One might ask what happened to the goats. The Air Force Office of Scientific Research took an interest and rescued them. There is an interesting story associated with that at The Story of the Transgenic Goats (continued).

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