Depends on what your margin for error is. In other words, define "worthless."
In general, I update keps weekly. But for most LEOs and casual ham operation, you could probably go 90 days or more and still find most birds with your Arrow and handheld within a few minutes.
For ISS or other spacecraft with the ability to adjust the orbit with thrusters, etc., you'd only be good until the next orbit boost. -- Mark D. Johns KØJM / MØGZO / ex-9H3DJ / ex-KØMDJ Brooklyn Park, MN USA EN35hd ----------------------------------------------- "Heaven goes by favor; if it went by merit, you would stay out and your dog would go in." ---Mark Twain
On Sat, May 12, 2018 at 12:02 PM, Ron VE8RT ve8rt@yknwt.ca wrote:
I understand that there won't be a good answer for how old can TLE's be before they're of no use. If you were going to be offline for an extended period, roughly, for a LEO, how long would you go before they're worthless?
Ron VE8RT
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