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1

For the latest TLES you can use Celestrak; 1, 2, 3 and there are some collections of some historical (but not recent) TLEs as well. You can access a huge collection of historical TLEs in Space-Track after you register and read the rules. See this answer for more on that. When I first started I also though I'd have to scrape them from websites! See also ...


2

The numbering of 01-99 you refer to is the one used for the PRN of the satellites. The SVN is numbered using 3 digits in IGS files and is therefore not going to run out anytime soon. PRN's are often reassigned to different satellites, as this Wiki article shows. If you take a look at this ANTEX file you can see there are two identifiers, a double digit (e.g....


2

According to Silverbird, it may be that neither Atlas V 552 nor Falcon 9 block 5 can put 8.8 tons into the necessary 1200 km x 20000 km 55º transfer orbit. Silverbird's data is estimated, and has a fairly wide band of uncertainty, so it might be possible on the Atlas, or the satellite might be able to expend more of its own delta-V to complete ...


41

Could you fit all six into a FH fairing? If not, would a slightly larger one be enough? I can't find dimensions for GPS III sats, but this Lockheed Martin image shows how much of a Delta Medium 4-meter fairing is taken up by a single one: Looking at the dimensions of the fairing in the Payload Guide, I think the satellite is about 5m long by 2.5m wide. ...


7

Originally, it was because the GPS satellites are heavy. An Atlas E/F with SGS-1 upper stage could just barely put a GPS Block I satellite into a 12-hour orbit, while the Delta II was designed around placing a single Block II satellite into orbit at a time. Now, it's because the constellation is complete. GPS Block III satellites are being launched to ...


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