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Old May 26th 19, 05:32 PM posted to sci.space.policy
Niklas Holsti
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Posts: 168
Default Two Starships in "bolas" rotation

On 19-05-26 15:16 , Jeff Findley wrote:
...
Once
Starship/Super Booster is flying to earth orbit, its primary mission
will be Starlink satellite deployment. Yes you can keep flying up to 60
Starlink satellites at a time on Falcon 9 (more polar orbits will either
have less satellites or require Falcon Heavy launches), but when the
goal is on the order of 12,000 satellites (by the mid 2020s), that's at
least 200 Falcon/Falcon Heavy launches in a few short years! If we
guess those launches cost on average $50 million each, that's $10
billion in launch costs just to get the initial constellation up and
running!


According to Wikipedia, $10 billion is indeed the Starlink cost estimate.

Starlink launches would use the "satellite delivery" version of
Starship, right? So that has to be developed. But it seems to me that if
these things are reusable, and rapidly reusable, to the degree that
SpaceX is planning, one or two Super Heavy boosters and one or two
satellite deliverers should be enough to finish building Starlink and
maintaining it.

That is an operational use of Super Heavy and the Starship. If Starlink
proves to work after the minimal number of satellites is up, it seems
likely that SpaceX will be able to finance and run such Starlink
operations in parallel with further development of the crewed Starship
version and the Tanker version.

And keep in mind the lifetime of these satellites is relatively short
(from memory something like 3-5 years), so this isn't a "one time"
thing.


I think that lifetime refers to a failed, dead satellite, in the lower
orbits, yes? AIUI working satellites use ion engines that will extend
their lifetime.

(There are developments in air-breathing ion enginges for very low Earth
orbits that could make the lifetime independent of the launched
propellant mass.)

If Starlink is successful, SpaceX will be continuously launching
its own Starlink satellites for some time to come.


Yes, but if those launches are part of day-to-day Starlink operations,
reusing the same launchers, why should they prevent further development
aiming at Mars?

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Niklas Holsti
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