Author Topic: Integrating ITS and NASA for Mars missions  (Read 3408 times)

Online redliox

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Integrating ITS and NASA for Mars missions
« on: 09/26/2017 04:34 AM »
Since the unveiling of the SpaceX's Interplanetary Transportation System a year ago, we have already seen a few changes in their would-be-plans, namely: Red Dragon won't fly to Mars, and there will at least be a smaller version of ITS created.  Between now and the opening of the 2020s we will see further changes, many likely in response to competition from Boeing, Lockheed, OrbitalATK (soon to have a different amalgamated name), and Blue Origin.  Of course, what every enthusiast regarding Mars talks about is...the unofficial race between SpaceX and NASA itself.

Basically, I did a thought experiment on how SpaceX could cooperate with NASA.  Going by what's currently known, it could be boiled down to 2 different approaches each entity adopted: Mars surface v.s. Mars orbit.  NASA wants to eventually get down to the surface, but the way down there is convoluted by the politics of rocket scientists, aerospace industrialists, and actual politicians whose priority isn't really the Martian surface but things like generating jobs and money (which means if those goals are met they could care less about footprints on the red planet).  SpaceX, or more specifically Elon Musk, seems to have taken the Mars Direct approach close to heart and is attempting to merge it with a logistical approach.  However politics and engineering aside, again it boils down to arriving at Mars from orbit or directly.  Are the 2 approaches mutually exclusive though?

In a few previous threads, I spoke about the possibility of there being a mini-ITS (how prophetic eh?  8) ) and also that exploring the Martian moons could be factored in without requiring a logistics nightmare.  The best element NASA came up with that made some sense from ARM and part of some of the current Mars orbit plans is SEV, the Space Exploration Vehicle that is just a hair reminiscent of the Odyssey's pods from Arthur C. Clarke's 2001.  I looked at that, then the ITS setup, and thought "could these 2 work together?"

The would-be-mission setup (bare-bones version):
1) SEV-vehicle launched from Earth and, via solar electric, put into either Deimos or Phobos orbit.
2) 1st ITS launched unmanned and lands on Mars.
3) 2nd ITS launched with crew and lands on Mars.
4) Crew transfers to 1st ITS and launches to Deimos/Phobos orbit.
5) Rendezvous with SEV.
6) SEV performs a ~week-long visit to a Martian moon.
7) SEV returns to ITS.
8) ITS returns to Earth.

In this case, it's modeled after Mars Semi-Direct.  The ITS would retain the ability to bypass the moons and return to Earth if the SEV is compromised; the moon mission is optional.  The SEV does leverage current NASA work (ARM and otherwise) and, between fleeting moon visits, could double as a communication relay (especially if from Deimos orbit) and perhaps a means of retrieving launched Mars samples.  Also, the SEV could be launched ferrying a propulsion stage in case the ITS' ISRU or engines lack the means to fully return to Earth (Deimos' higher orbit would be more taxing as well for circularizing the orbit).

Tea Monster did the renderings for me some time ago, and also mentioned his thoughts about the upcoming 'mini-ITS' possibilities.  I will add a few further renderings he came up with in the near future.  Most likely I'll wait until after the IAC announcements to see what Elon thinks up next.
« Last Edit: 09/26/2017 05:08 AM by redliox »
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Offline Peter.Colin

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Re: Integrating ITS and NASA for Mars missions
« Reply #1 on: 09/26/2017 06:26 PM »
Nice Pics, cooperation is always a good thing!
It’s certainly possible, to do it like this.
But why not land with the BFS on both moons and then return to Mars to refuel?
Maybe NASA could also develop a huge tanker vessel in Mars Orbit, that is filled with Methalox produced on Mars and periodically topped off by a SpaceX tanker ship.
Methalox in Orbit has several advantages.
The tanks don’t need to land; the fuel needed to get fuel into orbit doesn’t need to be storred; less fuel is wasted in refuel-landings.
A lot of technology goes into such a tanker ship that NASA is perfectly capable of, and making another lander seems double work.
Also creation of other in situ resources, seems like a task for NASA.
« Last Edit: 09/26/2017 06:39 PM by Peter.Colin »

Online ThereIWas3

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Re: Integrating ITS and NASA for Mars missions
« Reply #2 on: 09/26/2017 08:12 PM »
Throwing in an entirely different propulsion technology just because one NASA center is working on it just complicates things.  The best place from which to explore Martian moons is from Mars, by Martian residents.  Imagine how much you could see just with optical telescopes on the Mars surface?  Yeah I know there is dust - but you are 30K times closer than here.
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Online spacenut

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Re: Integrating ITS and NASA for Mars missions
« Reply #3 on: 09/26/2017 08:54 PM »
When SpaceX gets ITSy going, maybe NASA should design missions and equipment around the launch capability of ITSy.  What size would the payload bay be on an ITSy?  Internally?  8m x say 15m and weigh around 100 tons.   

Online redliox

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Re: Integrating ITS and NASA for Mars missions
« Reply #4 on: 09/27/2017 02:06 AM »
When SpaceX gets ITSy going, maybe NASA should design missions and equipment around the launch capability of ITSy.  What size would the payload bay be on an ITSy?  Internally?  8m x say 15m and weigh around 100 tons.   

Well a thought that occurred to me while the ITS concept was relatively new was three-fold:
1) Subscale testing of hardware isn't unheard of; the closer in size to the intended vehicle/rocket the more relevant the data.
2) A 4:5 scale vehicle (i.e. 80% size) would have similar dimensions but only half the scaled mass of the final form.
3) While supporting 100 or even 50 passengers would be difficult, supporting a crew of 10 or less would be reasonably easy by comparison.

Regarding more recent events, consider this: the 9 meter diameter Elon plans is 75% the size of the original 12 meters he had in mind.  While done to accommodate his and NASA's current infrastructure, it means his mini-ITS will have a bit less than half its old mass.  Factors like rocket thrust, engine weight, and fuel capacity will naturally alter things, but weighing less when getting off the ground is good.  Assuming scale is simple, the dry mass of ITS would go from 150 mt to roughly 75 mt.
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Online redliox

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Re: Integrating ITS and NASA for Mars missions
« Reply #5 on: 09/27/2017 02:37 AM »
Throwing in an entirely different propulsion technology just because one NASA center is working on it just complicates things.

Correct, although many who favor electric propulsion would counter-argue that methalox is still infantile while SEP has been employed on a handful of probes and numerous satellites already.

My view on the matter is to segregate the systems to fitting vehicles.  The SEV, which would launch crewless and weigh substantially less than ITS, has the most to benefit from a SEP setup since it can take its time as well as remain stationed in a high circular orbit.  ITS would be meant to be crewed, quicker, and larger which benefits from chemical propulsion and its ISRU while sitting on Mars.

Boeing and Lockheed have massive plans (in the literal sense of mass) because everything is hauled from Earth.  SEP has a hard time efficiently moving very large items, whereas smaller vehicles like probes or SEV don't require nearly as much.  Likewise without refueling on Mars even a plan exclusive to high Mars orbit guzzles fuel.

The best place from which to explore Martian moons is from Mars, by Martian residents.  Imagine how much you could see just with optical telescopes on the Mars surface?  Yeah I know there is dust - but you are 30K times closer than here.

Also there's the fact you couldn't see the far sides of the moons or sample their dust.

I do agree that Mars is the best place to begin an exploration of its moons though.  Methalox could readily be manufactured on Mars and kept cool aboard ITS during the brief (less than a month) orbital stay by a moon, as opposed to Earth-hauled sources which would have to be chilled for months or be heavier storeable fuels like hydrazine.  This is why an orbital mission from Earth is a logistical nightmare, but surprisingly manageable if begun from Mars (on the return leg home) instead.
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Offline ncb1397

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Re: Integrating ITS and NASA for Mars missions
« Reply #6 on: 09/27/2017 02:52 AM »
When SpaceX gets ITSy going, maybe NASA should design missions and equipment around the launch capability of ITSy.  What size would the payload bay be on an ITSy?  Internally?  8m x say 15m and weigh around 100 tons.   

I've mused to myself about putting Orion in an ITS cargo bay as a daughter craft. The cargo bay doors on the original ITS did look to be about 5 meters x 5 meters.

Online redliox

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Re: Integrating ITS and NASA for Mars missions
« Reply #7 on: 09/27/2017 03:12 AM »
Nice Pics, cooperation is always a good thing!
It’s certainly possible, to do it like this.

I certainly like to think so too!

But why not land with the BFS on both moons and then return to Mars to refuel?

Short answer: ITS would make an awkward lander in micro-gravity.  SEV, on the other hand, was already conceived to operate in near-weightless-environs including the Martian moons.  Likewise a suited astronaut could do the job too, but even in LEO robotic arms are preferential and safer too; thus spacewalks at Mars would be dubbed "major no-no."

Assuming the ITS heatshields are designed for multiple reentrys with minimal restoration, a round trip back to Mars is possible.  However, bear in mind ISRU (especially in NASA-funded-startup phase) would take months to replenish ITS fully, and with the Martian moons' being 70% of the way in delta-v back to Earth a crewed trip with priorities would depart for Earth after the short moon mission.

Maybe NASA could also develop a huge tanker vessel in Mars Orbit, that is filled with Methalox produced on Mars and periodically topped off by a SpaceX tanker ship.
Methalox in Orbit has several advantages.
The tanks don’t need to land; the fuel needed to get fuel into orbit doesn’t need to be storred; less fuel is wasted in refuel-landings.
A lot of technology goes into such a tanker ship that NASA is perfectly capable of, and making another lander seems double work.

Where to store methalox would ultimately depend on where it's used most often.  Both are manufactured on planets, where rockets would also be launched from.  At least initially, it'd make the most sense to store it on the Martian surface.  However, in regards to Martian orbit, the depots you speak of would be of best benefit at Deimos or otherwise high Mars orbit if not simply shuttled directly elsewhere.  However when it comes to fuel, its best to obtain it from wherever you landed when possible; therefore Mars vehicles use Martian fuel, Earth uses Earthly fuel, and Lunar vehicles at least use Lunar oxygen (and either Earthly fuel or Lunar hydrogen if that polar ice is an option).

Also creation of other in situ resources, seems like a task for NASA.

Sadly they've had an entire generation to do so, but they have the burden of politics as well as shouldering numerous projects simultaneously in fairness.  The Mars Society, and possibly SpaceX, have spearheaded the effort.  The MOXIE experiment on the 2020 Rover, if all goes well, could become the model for a supplemental system of LOX manufacture applicable to supplying either life support or rocket propellant.  I would expect that to be NASA's main ISRU contribution while commercial entities tackle methalox-via-Sabier reactors.

As you said earlier:
cooperation is always a good thing!
I don't believe NASA alone can do it, but with a dedicated partner (like SpaceX most obviously) the possibility is greater!  :)
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Online redliox

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Re: Integrating ITS and NASA for Mars missions
« Reply #8 on: 09/27/2017 03:20 AM »
I've mused to myself about putting Orion in an ITS cargo bay as a daughter craft. The cargo bay doors on the original ITS did look to be about 5 meters x 5 meters.

Here is a size reference for the rover-variant of SEV to consider.  More than likely there will be some cargo offloaded to Mars by (mini or otherwise) ITS, but I don't know if a full-blown, pressurized crew vehicle would be among them; an unpressurized but modernized version of the lunar "dune buggy" rover would be more feasible since it can be folded.

Orion at Mars would be, to put it bluntly, little more than a glorified paperweight.  Useful life support for a lunar mission, but vastly under-powered propulsion is its Achilles heel.  Lockheed just wanted an excuse to build more on NASA's bill.
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Offline su27k

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Re: Integrating ITS and NASA for Mars missions
« Reply #9 on: 09/27/2017 04:17 AM »
The would-be-mission setup (bare-bones version):
1) SEV-vehicle launched from Earth and, via solar electric, put into either Deimos or Phobos orbit.
2) 1st ITS launched unmanned and lands on Mars.
3) 2nd ITS launched with crew and lands on Mars.
4) Crew transfers to 1st ITS and launches to Deimos/Phobos orbit.
5) Rendezvous with SEV.
6) SEV performs a ~week-long visit to a Martian moon.
7) SEV returns to ITS.
8) ITS returns to Earth.

You lost me on step 3, are you saying the first human landing on Mars is not a SpaceX/NASA cooperation? Or is this thread about how to explore Deimos/Phobos after Mars landing? If it's the latter, I think the title should be modified to reflect this. If it's the former, well I just don't see how it could happen, no way SpaceX is going to Mars alone.

Online redliox

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Re: Integrating ITS and NASA for Mars missions
« Reply #10 on: 09/27/2017 05:40 AM »
The would-be-mission setup (bare-bones version):
1) SEV-vehicle launched from Earth and, via solar electric, put into either Deimos or Phobos orbit.
2) 1st ITS launched unmanned and lands on Mars.
3) 2nd ITS launched with crew and lands on Mars.

You lost me on step 3, are you saying the first human landing on Mars is not a SpaceX/NASA cooperation? Or is this thread about how to explore Deimos/Phobos after Mars landing? If it's the latter, I think the title should be modified to reflect this. If it's the former, well I just don't see how it could happen, no way SpaceX is going to Mars alone.

It is the former.  What I specify are the active vehicles.  NASA would more than likely want additional support either on the ground or in orbit.  There could be habitats on the surface or a backup propulsion stage in orbit brought in alongside the SEV.  NASA will want both cause to keep the astronauts comfortably safe and aerospace industrialists funded during the stay on Mars; this is why I mentioned "bare-bones version."

Also, because ITS is mentioned, it felt a better fit to place the thread here under SpaceX Mars.
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Offline Norm38

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Re: Integrating ITS and NASA for Mars missions
« Reply #11 on: 09/27/2017 12:57 PM »
Is there enough gravity on Phobos/Deimos for a wheeled rover? Escape velocity is 40km/hr. I'd hate to hit a bump at anything more than a slow crawl. Or is the rover only for Mars?
« Last Edit: 09/27/2017 01:00 PM by Norm38 »

Offline ncb1397

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Re: Integrating ITS and NASA for Mars missions
« Reply #12 on: 09/27/2017 05:12 PM »
I've mused to myself about putting Orion in an ITS cargo bay as a daughter craft. The cargo bay doors on the original ITS did look to be about 5 meters x 5 meters.

Here is a size reference for the rover-variant of SEV to consider.  More than likely there will be some cargo offloaded to Mars by (mini or otherwise) ITS, but I don't know if a full-blown, pressurized crew vehicle would be among them; an unpressurized but modernized version of the lunar "dune buggy" rover would be more feasible since it can be folded.

Orion at Mars would be, to put it bluntly, little more than a glorified paperweight.  Useful life support for a lunar mission, but vastly under-powered propulsion is its Achilles heel.  Lockheed just wanted an excuse to build more on NASA's bill.

Adding 2 Orions would add 1.5-2 km/s of total vehicle maneuverability to the original ITS. Adding one adds about 1 km/s. Frankly, things impossible to do with either alone could be done with them together. Not to mention it is nice to have a dissimilar redundant system when your main vehicle has an issue.
« Last Edit: 09/27/2017 05:17 PM by ncb1397 »

Offline philw1776

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Re: Integrating ITS and NASA for Mars missions
« Reply #13 on: 09/27/2017 06:32 PM »
I've mused to myself about putting Orion in an ITS cargo bay as a daughter craft. The cargo bay doors on the original ITS did look to be about 5 meters x 5 meters.

Here is a size reference for the rover-variant of SEV to consider.  More than likely there will be some cargo offloaded to Mars by (mini or otherwise) ITS, but I don't know if a full-blown, pressurized crew vehicle would be among them; an unpressurized but modernized version of the lunar "dune buggy" rover would be more feasible since it can be folded.

Orion at Mars would be, to put it bluntly, little more than a glorified paperweight.  Useful life support for a lunar mission, but vastly under-powered propulsion is its Achilles heel.  Lockheed just wanted an excuse to build more on NASA's bill.

Adding 2 Orions would add 1.5-2 km/s of total vehicle maneuverability to the original ITS. Adding one adds about 1 km/s. Frankly, things impossible to do with either alone could be done with them together. Not to mention it is nice to have a dissimilar redundant system when your main vehicle has an issue.

I must be missing something.  The mass of the 2 Orions counts against ITS's Km/sec for a given payload.  Orion is far less ISP efficient than ITS.
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Offline ncb1397

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Re: Integrating ITS and NASA for Mars missions
« Reply #14 on: 09/27/2017 06:35 PM »
I've mused to myself about putting Orion in an ITS cargo bay as a daughter craft. The cargo bay doors on the original ITS did look to be about 5 meters x 5 meters.

Here is a size reference for the rover-variant of SEV to consider.  More than likely there will be some cargo offloaded to Mars by (mini or otherwise) ITS, but I don't know if a full-blown, pressurized crew vehicle would be among them; an unpressurized but modernized version of the lunar "dune buggy" rover would be more feasible since it can be folded.

Orion at Mars would be, to put it bluntly, little more than a glorified paperweight.  Useful life support for a lunar mission, but vastly under-powered propulsion is its Achilles heel.  Lockheed just wanted an excuse to build more on NASA's bill.

Adding 2 Orions would add 1.5-2 km/s of total vehicle maneuverability to the original ITS. Adding one adds about 1 km/s. Frankly, things impossible to do with either alone could be done with them together. Not to mention it is nice to have a dissimilar redundant system when your main vehicle has an issue.

I must be missing something.  The mass of the 2 Orions counts against ITS's Km/sec for a given payload.  Orion is far less ISP efficient than ITS.

Dry mass of Orion is an order of magnitude lower than ITS. It is like staging a rocket vs SSTO even with hypergolics for the upper stage.

Offline philw1776

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Re: Integrating ITS and NASA for Mars missions
« Reply #15 on: 09/27/2017 06:44 PM »
I've mused to myself about putting Orion in an ITS cargo bay as a daughter craft. The cargo bay doors on the original ITS did look to be about 5 meters x 5 meters.

Here is a size reference for the rover-variant of SEV to consider.  More than likely there will be some cargo offloaded to Mars by (mini or otherwise) ITS, but I don't know if a full-blown, pressurized crew vehicle would be among them; an unpressurized but modernized version of the lunar "dune buggy" rover would be more feasible since it can be folded.

Orion at Mars would be, to put it bluntly, little more than a glorified paperweight.  Useful life support for a lunar mission, but vastly under-powered propulsion is its Achilles heel.  Lockheed just wanted an excuse to build more on NASA's bill.

Adding 2 Orions would add 1.5-2 km/s of total vehicle maneuverability to the original ITS. Adding one adds about 1 km/s. Frankly, things impossible to do with either alone could be done with them together. Not to mention it is nice to have a dissimilar redundant system when your main vehicle has an issue.

I must be missing something.  The mass of the 2 Orions counts against ITS's Km/sec for a given payload.  Orion is far less ISP efficient than ITS.

Dry mass of Orion is an order of magnitude lower than ITS. It is like staging a rocket vs SSTO even with hypergolics for the upper stage.

The post said ADDING 2 Orions to ITS
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Offline ncb1397

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Re: Integrating ITS and NASA for Mars missions
« Reply #16 on: 09/27/2017 06:51 PM »
I've mused to myself about putting Orion in an ITS cargo bay as a daughter craft. The cargo bay doors on the original ITS did look to be about 5 meters x 5 meters.

Here is a size reference for the rover-variant of SEV to consider.  More than likely there will be some cargo offloaded to Mars by (mini or otherwise) ITS, but I don't know if a full-blown, pressurized crew vehicle would be among them; an unpressurized but modernized version of the lunar "dune buggy" rover would be more feasible since it can be folded.

Orion at Mars would be, to put it bluntly, little more than a glorified paperweight.  Useful life support for a lunar mission, but vastly under-powered propulsion is its Achilles heel.  Lockheed just wanted an excuse to build more on NASA's bill.

Adding 2 Orions would add 1.5-2 km/s of total vehicle maneuverability to the original ITS. Adding one adds about 1 km/s. Frankly, things impossible to do with either alone could be done with them together. Not to mention it is nice to have a dissimilar redundant system when your main vehicle has an issue.

I must be missing something.  The mass of the 2 Orions counts against ITS's Km/sec for a given payload.  Orion is far less ISP efficient than ITS.

Dry mass of Orion is an order of magnitude lower than ITS. It is like staging a rocket vs SSTO even with hypergolics for the upper stage.

The post said ADDING 2 Orions to ITS



From Deimos transfer, Orion could get to Deimos and back. The 2nd Orion could get to Phobos and back from Phobos transfer. It is cheaper than taking the big craft to each. If you are doing exploration with smaller crews in the 4-6 range, it makes sense.
« Last Edit: 09/27/2017 06:52 PM by ncb1397 »

Online redliox

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Re: Integrating ITS and NASA for Mars missions
« Reply #17 on: 09/30/2017 04:40 AM »
Elon Musk's announcement was a pleasant surprise regarding ITS (soon to be changed).  The bigger surprise was his offer to service the ISS...and presumably the DSG next.  THAT is an example of integrating SpaceX and NASA together, although honestly I did not expect it to include shuttle-esque servicing.

While the bit with the ISS isn't exactly Mars-centric, it now leads me to wonder how they'll handle airlocks and docking.
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Offline TomH

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Re: Integrating ITS and NASA for Mars missions
« Reply #18 on: 09/30/2017 06:39 AM »
Only if it is on SpaceX' terms. The last thing they need is a cadre of US senators to start micro-managing and regulating SpaceX' every little move.

What I'd rather see is Bezos to realize that Blue is in a difficult position competitively and to offer to cooperate with or become a 49% partner with Musk. Their combined resources would be impressive. Before anyone says that's impossible, four cutthroat bankers who were millionaire (in today's funds) competitors during the gold rush combined resources as owners of the Central Pacific Railroad Company and became billionaires together building the transcontinental railroad.

Offline Nibb31

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Re: Integrating ITS and NASA for Mars missions
« Reply #19 on: 09/30/2017 07:02 AM »
While the bit with the ISS isn't exactly Mars-centric, it now leads me to wonder how they'll handle airlocks and docking.

They don't need airlocks. But docking the BFR with the ISS is going to put a lot of mechanical stress on the IDS.

The bigger issue is getting NASA to certify BFR for ISS operations, and SpaceX implementing any changes, before ISS is retired. I don't see that ever happening.

Tags: Mars SpaceX NASA Deimos Phobos