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New video about a full TAL to Istres


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I was hoping for actual date guesstimates: timing is everything. If there are only one or two Crew Dragon flights left after Starship is certified, then SpaceX will eat the loss and fly Crew dragon at a loss once or twice, and maybe keep flying Cargo Dragon for CRS. If there are (say) four more CCP flights after Starship is certified, they might get creative and come up with a way to use Starship.
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Concerning artificial gravity, I decided to play with a few numbers on spincalc for a simple jogging track.

The typical jogging speed on earth is about 4-6m/sec (https://www.healthline.com/health/average-jogging-speed)
Allowing for some hull and shielding thickness, a track might conservatively have a 4m radius. (8m diamiter+1/2m hull/shielding on each end)

At 4m/s floor tangent and a 4m radius, your feet will be experiencing 0.4g at 9.55 rotations per minute
At 5m/s floor tangent and a 4m radius, your feet will be experiencing 0.637g at 11.9 rotations per minute
At 6m/s floor tangent and a 4m radius, your feet will be experiencing 0.918g at 14.3 rotations per minute

Assuming a 2m tall person, their head will have the same rotation per minute as their feet but a 2m radius of rotation.


At a 2m radius, your head will be experiencing 0.2g at 9.55 rotations per minute
At a 2m radius, your head will be experiencing 0.32g at 11.9 rotations per minute (just below marsG)
At a 2m radius, your head will be experiencing 0.46g at 14.3 rotations per minute

This assumes the starship itself is not spinning at all- this is strictly individual movement, so intermediate axis isnt even an issue. These G loads dont seem unreasonable, though the difference between head and foot might take a bit of getting used to.

Also, this doesnt even need a specialised ship- you could easilly have a jogging track/outer corridor in the lunar starship for physiological testing between excursions.
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Yes, of course, gimbals are required even for coplanar satellites.

The issue arises when there is a user in a different plane and a different altitude. Depending on the relative positions of the satellite and the user, the slew rate of the gimbals may be very high.

Also, apart from generally pointing the user receiver upwards, where do the user ISR(s) affix to the spacecraft?
If the slew rate is "very high", then you should not attempt to establish an ISL. Pick a satellite that is farther away or is moving in a more appropriate direction.

One popular theoretical approach is to place your major networking satellites at a higher altitude. the usual lower-altitude satellites connect in rings, one per orbit, and several satellites in each ring connect up to the higher "network". The satellites in the "network" do not serve terrestrial users, but they have lots of ISL with each other.
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Due to start in just over 2 hours:

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Missions To The Moon (HSF) / Re: Artemis 1 Discussion Thread
« Last post by AS_501 on Today at 06:20 pm »
FTS batteries will be now serviced in the VAB?
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Missions To The Moon (HSF) / Re: Artemis 1 Discussion Thread
« Last post by Orbiter on Today at 06:19 pm »
The majority of the launch windows, including the ones with long launch windows, are at night for the next two periods. It's hard for me to imagine NASA will purposefully aim for a day launch if the windows to do so are so limited.

https://twitter.com/NASASpaceflight/status/1574459046882676738/photo/1
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Do we have even rough ideas of a timeline for Polaris 2?

Will Polaris Dawn slipping back 3 months likely push it back as well?

My expectation is that Starship orbital flight would be more responsible for pushing back the second Polaris mission. I don't think Starship *landing* would impede Polaris 2 per se, but landing obviously should be at the top of the priority list after that.
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