Comment: Re:Full article hidden inside pay-wall (Score 1) 64
Thanks, but he was referring to the Nature article itself, i.e. the scientific publication: "Embryology of Early Jurassic dinosaur from China with evidence of preserved organic remains".
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Thanks, but he was referring to the Nature article itself, i.e. the scientific publication: "Embryology of Early Jurassic dinosaur from China with evidence of preserved organic remains".
You missed the point: you can bring in large empty bottles, or small bottles filled with liquid, but not large bottles with a small amount of liquid. The regulations are arbitrary and near-useless.
The video is for Chrome(ium), WebKit, and now Blink developers, not for the end users or the browser(s).
Heh.. Proof right there that you're not affiliated with a US government agency.
That's right, I'm not, and neither are the developers of STRaND-1. I'm not even American. The world is a big place, not all of it is funded by the US government.
Off-the-shelf hardware, though - that would be a bigger deal. It's doomed to failure, but if somehow it could work that would be huge.
Why do you say that? We use COTS hardware pretty much everywhere in our missions. It turns out that the radiation environment isn't really that terrible if you are below the Van Allen belts. Why pay through the nose, both in terms of dollars and in terms of horrendous lead times, for space-qualified parts when commercial, industrial, and automotive parts work just fine?
Precisely; her comments have absolutely nothing to do with the demand of higher speeds and quality service, but rather the supply. Her argument is circular -- we don't offer good options, so customers don't choose good options, therefore customers don't want good options, thus there's no need for us to offer good options. That's an awesome flow chart you got there, TWC.
I should clarify my first sentence: the prime contractor for SAPPHIRE is MDA, the customer being the Department of National Defense. It is the BRITEs that were developed for Austria by SFL.
Also on the PSLV-C20 launch are the Canadian military satellite SAPPHIRE, and the twin spacecraft BRITE-Austria and UniBRITE, developed in Canada for TU Graz and University of Vienna respectively. ISRO put out a pretty good brochure describing the launch.
You can find some good photos of the stacking and launch vehicle integration here, here, and here. You can watch the launch live on Monday morning here.
Needless to say, we're all pretty stoked around here ^__^
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.
If you learn one useless thing every day, in a single year you'll learn 365 useless things.