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What's the problem with an escort?  I used to be a foreign national, and got escorted around a whole bunch...  usually with everyone eye-rolling, but I was just happy there were procedures in place.

Extra costs and people
I don't see that as a problem.  Of course an escort requires that.  ???

Question.  Would SpaceX have to copy LC-39A's emergency facilities exactly or would they be allow to "innovate"?  I could see two different emergency scripts depending on LC being a pain but curious if anyone has a more concrete answer.

Specifically, is the pad escape system requirements or risk driven?

It’s not obvious that a zip wire escape system would significantly reduce risk compared to hunkering down in Dragon and trusting in the LES, in particular for a vehicle where the crew are strapped in, the CAA is retracted, and the LES is armed prior to prop load.

Slidewire or similar escape systems are not for crew who are already strapped into the capsule for launch.  It's for anyone working on the tower in case of an emergency or if other means of exit are blocked, particularly in the case of a fire.
There seems to be a lot of opinion and uncertainty in the area of planetary protection probably because the matter really hasn’t be properly looked at recently. I suspect that the critters in Congress won’t want to go there at the moment, because no human mission is likely any time soon so why do today what you can put off until tomorrow? Not only that, but more information may be available in the future to help inform a decision (after the Mars sample return mission for example).

When the time comes I would expect the US Administration to take the lead, prepare the ground and ensure that appropriate changes were put in place (no doubt after extensive discussion and negotiation with a range of stakeholders in public and private). Any such changes would be likely to go hand in hand with a space policy announcement about human Mars landings.

It’s hard to say what any future planetary protection rules might state in any detail, but they would surely make it clear who the regulatory body was, would give at least a passing nod to the idea of “harmful contamination” and allow non-harmful contamination within bounds to enable humans to visit.
I would say that all the vehicle in the story can be self driving, or remote controlled.  However, many of them can also be driven from the cab, for situations that were not provided for in the design and that a limited AI cannot handle.
There are cab-less vehicles, such as trucks on regular runs, mining trucks, etc.
And the Landcruiser doesn't actually have a driver's seat.  It can be controlled from any computer console.  To the chagrin of the owners, after all that's how it was hijacked in the first place.
I think you have covered it well. I can think of useful add-on for cab-less vehicles. A jump seat on the front bumper to drive it back to the shop if self drive is having a issue. Maybe a cabinet with emergency supplies like a blowup shelter, comm gear and first aid stuff? This is fun.
Glad you're enjoying the story and discussions!

Interesting idea, although if the vehicle is entirely 'fly by wire' the added control from a local panel and seat might be limited.  The question is already here in the real world, with non mechanical steering and electronic brakes and self driving vehicles.
Eventually, as you add features to the seat, you reach the point where you might as well have a cab. 
The cab also provides an airlock, so it can be a shirtsleeves work environment.  but as happens earlier in the story, the airlock door is not always reachable... :)
This will depend on how vehicles are really used on Mars and how easy getting in and out of a spacesuit can be.  In the world of the story, most older vehicles will have cabs, while many newer ones might do entirely without.  As the Mardsen mine is broke, they use old equipment with cabs.
Alternatively, or additionally, it adds another backup to the Starship landing, where three engines light, and one is shut down to land on (the minimum and maximum of?) two.
If there is a problem after relight with one of those two engines, this tests quickly relighting that third engine.
Why not do the servicing mission with Polaris Dawn?  They've given themselves extra training time. 

It does strike me as a wild thing to do on the crews first EVA.  I'm not sure it's wilder than the missions NASA's own astronauts have done on their first missions?

This would not be done on the first Polaris Dawn flight.

A Hubble servicing mission would be a separate NASA-run flight.

Question, does anyone know? How many astronauts that have done Hubble servicing are still in the active astronaut corps?

Megan McArthur and Drew Feustel are the two remaining STS-125 crew members still active.

Note that Megan McArthur has flown on a Crew Dragon (Crew 2). She operated the shuttle robotic arm on STS-125. Drew Feustel was one of the four spacewalkers on STS-125.

Drew Feustel did three EVAs to service Hubble on STS-125, including to replace the Advanced Camera for Surveys (which was not originally intended to be servicable), and replacing batteries, so he's very familiar with Hubble. He's got to be 100% the go-to EVA guy if there is a new Hubble servicing mission.

Megan McArthur was STS-125's robotic arm specialist and was the last person to "touch" Hubble. She's already familar with the Dragon spacecraft.

Having both onboard such a mission would be both appropriate and fitting.
I would expect that the whole transfer port and support structure could be sent up as a single Starship package, with any extra mass capacity being used to carry up propellant for other uses.
In this proposal, the center of the station does not need not be the center of rotation.

The outer yellow structure can be moved to always be on the center of rotation (about 1m of travel).  It matches the green structure on the non rotating station and provides a rotating connection point that transmits no force to the non rotating station except whatever in needed to keep the two elements aligned.

The airlock acts like a shuttle.  The operation is as follows:
-Starts attached to the rotating section and turns with it.
-When it is loaded with passengers, or cargo, it closes the rotating side hatch.
-It moves away from the spinning station and spins down to 0.
-Its support structure moves to align with the center of the yellow ring, it is then aligned with the non rotating station, but supported by the rotating station.
-It moves sideways and connects up with the non rotating station, the outer door opens and materials and people transfer.  At this point is is held by the non rotating section and is turning in its support structure.  Or in another frame of reference is is now fixed to the non rotating section and the support structure is rotating around it.

The shuttle doesn't have to start at the center of the rotating section, it just need to be able to be moved to align with the center of rotation.

Larger versions of this can provide multiple tracks and multiple entry points.

Power is transmitted by induction rings, and information is transferred by high frequency link or optically.

I guess it could just be defining the parameters of the start box, but I bet they want to know how quickly they can get the booster headed back after ship separation.
That would imply an evaluation of alternatives to the "baseline" separation concept in which the Booster would pitch up into a power-on backflip while the Ship separates under centrifugal force (like Starlink v1.x). That approach would not require an engine restart event until the landing burn. But if they want to do the stage separation more like Falcon RTLS with a MECO followed by a boostback burn, then this would be the type of engine test they'd want to run.

The "flippin' stage" maneuver will be cool to see them attempt, but maybe it's prudent to have a backup plan involving a MECO and a set of electric linear actuators to effect a positive stage separation (improvement over pneumatic pushers for reusability).

Or maybe a combo. Start power flip, separate, kill engines, wait for rotation to complete,  then restart engine subset and head home. Why boost the wrong direction for 9 seconds or whatever. Save fuel and reduce stress instead at the risk of complexity?

Wouldn't it be better to: Start power flip, kill engines, separate, wait for rotation to complete,  then restart engine. That way avoiding recontact of SS and SH?
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