Yeah, you can have omnidirectional antenna coverage for both uplink and downlink. Our S-band transmitter is capable of 1 Mbps omnidirectional downlink at 650 km. This is the preferred method if you can close your link and data budgets because it makes the system vastly simpler and inherently fail safe (if it crashes and you lose attitude control, you can still talk to it). A secondary directional downlink may be reasonable if you have very high data requirements (e.g. streaming video or ultra high definition imagery), but generally speaking you never want to be in the situation where you can't talk to the spacecraft if it can't point at you, even in big space.

Generally speaking, microsatellites are in the range of 10 kg to 100 kg. What you are talking about are cubesats, which are generally nanosatellites (1 kg to 10 kg) and picosatellites (< 1 kg). As others have said, the AMSAT programme is a great starting point; next August come out to the Cubesat workshop and, if interested, hang out for the USU Small Satellite Conference; lots of industry, academia, and government representation. We host a booth every year, as do most relevant players in North America.

A metal cube in low Earth orbit will equilibrate to about 25C if you cover the outside with solar cells and some reflective tape. The radiation environment isn't really all that bad below the Van Allen belts; use automotive grade parts and in general you'll be fine. No need to worry about lubricants because you shouldn't have any mechanical actuators (unless it's part of your payload or you really want to fly a reaction wheel). Good thermal ground planes in your boards and metal bosses tieing them to the structure will move heat away from components just fine. No need for a "point-or-die" solution, just put solar cells on all faces of your satellite; if you lose control authority (e.g. computer crash) you still generate enough keep-alive power. Gravity doesn't really have any impact unless your payload is a mechanical actuator, which again is not very common at the amateur cubesat scale. Leaks -- don't use pressurized gases or fluids; evaporation, just pick materials with < 1% total mass loss and less than 0.1% CVCM (i.e. Teflon insulation on wires instead of PVC).

As it turns out, amateur space isn't all that hard to do.

No mod points right now, but thanks for the clarification.

I would get it, but I don't believe it.

Tin whisker growth is another way not directly related to the flash cells. Commercial electronics use lead-free solder and no real whisker mitigation techniques. Eventually a whisker shorts between two things that shouldn't be shorted, conducts sufficient current for a sufficient amount of time, and poof, your drive is dead.

Whatever.. not interested in a reiteration war.

Arguments like yours annoy me on a few levels. First, you've already prejudiced yourself by declaring that you don't think highway driving is a reasonably safe mode of transport. Second, you seem to think that 25% more travel time is unacceptable -- when I travel back to my hometown every few weekends, I experience much greater variation in my travel time than 25% just based on the traffic and whether it is a holiday weekend or not. You've also neglected that most people driving for more than three hours tend to stop and take a break, even if it is not over lunch, e.g. to visit a restroom, buy a bottle of gatorade, whatever.

Third, I don't understand what you mean by "I don't know who has that kind of time on the road" -- just about anyone that is taking a long-distance trip, that's kind of the whole point! Lastly, you indicate that because it is not an ideal perfect solution, it has no business being here at all. Of course they have a lot of work to do, the entire electric vehicle industry is barely entering its infancy; but if technology developers don't push for change to happen, it never will. This is a good step in the electric vehicle industry, and I hope that it increases demand for technological development.

Quantum key exchange via satellite: QEYSSat.

You were with me until your stupid protocol argument. DNS and TCP/IP in general are used for many more things than just HTTP requests.

They are saying that their experimental results fit the predictions of the Standard Model Higgs boson, to a relatively high confidence level. This is the best that you can hope for from any scientific experiment.

Not in this case; there was an extra washer installed on one side of the arm mount for the mirror grinder, meaning that the arm was skewed. I agree with your general sentiment of reducing areas of potential confusion, though.

I prefer a "thou"; less ambiguous than "mil", which could be confused for "millimeter" (granted, one should not be shortening millimeter to mil).