Since the path that the launch vehicle will take is very well defined (unless something goes wrong!), and the paths of most objects that would intersect this path can be predicted, it becomes a juggling act to get a time when the launch vehicle will have a clear path, and your ground assets are available.
Since it takes a certain amount of time to get the launch vehicle ready, you work "backwards" from when you know your path will be clear on your trajectory to determine when you start your countdown.
The launch provider I work for has several people who do nothing but plan things like this, in coordination with USSTRATCOM, NASA, the FAA, the European Space Agency, the Russian Space Agency, and all the other other launch providers.
In the 9 years I've been doing my part (Communications, Range, and Telemetry) we've only had one "external" hold, and that was caused by NASA having to move the ISS a bit because the ISS was going to have a close approach of some space junk.
It's called a COLA (COllision Avoidance) hold, and if everybody does their planning properly, doesn't usually cause a problem.
One of the things considered is the ascent speed of the launch vehicle, as it's going pretty fast during it's passage through various altitudes.
HTH!
73, Jim KQ6EA
On 09/24/2013 04:22 AM, MICHAEL wrote:
For the longest time I have been wondering how a satellite is placed in orbit without hitting anything else? I have seen pictures of all the stuff circling the Earth and it just baffles me how anyone can get anything in orbit without hitting anything. Can anyone explain this?
Mike/N8GBU
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