Low orbit altitude is defined as 100 - 1240 miles high. Any pilot that goes over 50 miles up or higher gains an astronaut rating. The lower the orbit, the lower the speed needed. I don't know what altitude will sustain a satellite for 3 months, but I would think it can lower than 100 miles. Anyone?
In the articles I've seen on space debris, I haven't seen anything about clean-up. Not sure you can. NASA is tracking it, though. As for a satellite that disposes of itself, I don't see how that happens in space unless it is sent into the atmosphere, which would burn it up.
It's good these satellites are launched in a way they become self-disposing. But touting the price ignores the cost/benefit ratio.Yes, they are a fraction of the cost, but you get a small fraction of the capacity, for a small fraction of the coverage area, for a small fraction of the day, for a small fraction of the nominal service life of other SATCOM systems.There is nothing lost in looking at technologies, and plenty to be gained from a pragmatic evaluation of the VALUE of these kinds of solutions.Sometimes it just makes sense to spend more, add another future-junk-satellite to the list, and get greater utility out of our tax dollar.
Beth, it depends on how high the debris is. Junk in LEO will come down by itself, eventually. Skylab did, as did Kosmos 954 (scattered radioactive debris over a 600 km swath of Canada in 1978). They were in fairly low orbits.
The toolbag that slipped away from a spacewalking astronaut in November 2008 eventually reentered in August 2009. The space station orbits at about 230 miles above the surface.
The higher the junk is, the longer it stays up. Satellites in geosynchronous orbit (22,000 miles aren't going to come down, which poses a different problem. The geosynchronous orbit is unique (a satellite orbiting the equator at that altitude appears motionless to an observer on the ground), and the real estate there is precious. When geosynch satellites are decommisioned, they now get boosted even higher, up out of that special orbit, to make room for new satellites.
Cleaning up the orbitals is going to cost. Getting some sort of device up there to pick up the garbage is going to cost $2000-$10000 per POUND just to get the device into orbit.
Naperlou, thanks for your thoughts on the launch issue. My first reaction when I saw this video is, how can they launch so easily? (Anyway, it looks easy in the video.) NASA's fabled X-programs spent decades trying to launch aircraft (like the National Aerospace Plane) into space, with limited success. They found that flying into space is difficult. That's why NASA spent so many years dropping gigantic multi-million-dollar booster rockets into the ocean. So how are they able to launch these things into space with such apparent ease?
Beth, space junk has been a growing problem for decades. The idea of sending yet more trash into orbit appalls me, too. The only "disposable" products of any kind we should be making these days should be compostable or recyclable. The myth that things can be thrown "away" becomes even m ore obvious when you look at space junk. There is no "away" in a closed system.
I guess I'm either naive or aren't as up to date on the current state of space exploration. I am absolutely appalled by that news. Does anyone know if we have programs to clean it up or if that is even possible? What happens to the debris--it just floats around forever?
Engineers at Fuel Cell Energy have found a way to take advantage of a side reaction, unique to their carbonate fuel cell that has nothing to do with energy production, as a potential, cost-effective solution to capturing carbon from fossil fuel power plants.
To get to a trillion sensors in the IoT that we all look forward to, there are many challenges to commercialization that still remain, including interoperability, the lack of standards, and the issue of security, to name a few.
This is part one of an article discussing the University of Washington’s nationally ranked FSAE electric car (eCar) and combustible car (cCar). Stay tuned for part two, tomorrow, which will discuss the four unique PCBs used in both the eCar and cCars.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.