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I gave this a lot of thought last evening, and analyzed my objections to "going totally solar."
It's based, as (th) says, a lot of wishful thinking. The Main purpose of early missions is more about overall survival and doing science than building a Utopian Solar Society. In my 17 crew thread, I haven't included a massive solar farm because there is simply too much other work to accomplish.
I'm also of the opinion that if Louis wants to see a massive Solar Farm, he visits California. I personally believe that there is another form of pollution he's inadvertently promoting: visual pollution. I remember a particular line from "the Martian, which was Mark Watney strolling alone and mentally commenting on the "Magnificent Desolation." I cannot tolerate the thought of that Magnificent Desolation being turned into an unsightly Solar Farm.
kbd512 has done an excellent job of "doing the math," and his conclusion is inescapable: no matter how much the Solar Only group wants it, "it ain't gonna happen."
On one hand, Louis is talking about promoting Space Tourism; on the other hand, he wants to defile the Red Planet with square kilometers of solar panels. I sure as H*ll don't want to go to see a Solar Farm, if I'm spending a $500,000 amount to see Mars.
Space Tourism to the Moon will be fairly popular, and will remain expensive. Similar to a guided expedition to Mt. Everest, which costs $50,000 (actually more now--this number is several years old). There will be curious adventurers at first, but it's also not going to become a family vacation destination.
Louis-
All major airports have elements of what is called the WAAS system, which is the acronym for Wide Area Augmentation System. This is composed of several strategically placed transponders on the ground to aid and assist the onboard GPS navigation system. My airplane had a Garmin 550 on board and was "WAAS enabled." This system is essential for landing aircraft to know their altitude with a high degree of accuracy. The transponders are surveyed in place with exact altitude included. GPS is great for position in map coordinates, but not good enough to land an airliner.
Landing any airplane in gusty and crosswind conditions is a real art, and pilots spend hours practicing these a lot. I flew out of Casper, WY (KCPR) for most of the years while I still had a medical certificate. Crosswind landings are moderately difficult themselves, but when gusty conditions are added to the equation, it's a whole new ballgame. Every pilot develops a set of personal guidelines as to how windy it can get and still safely take off and land the airplane
GW is correct that there isn't any autoland system capable of landing ANY airplane under gusty conditions, but routine landings under standard conditions are routinely done by the landing system computer--with a pilot having hands on the controls to deal with sudden and unexpected gusts.
TH--I am well aware of the electronic control systems response time being in the millisecond range; it's not possible to make physical systems respond fast enough; especially as big as they are getting.
OK, I understand now that you've pointed that out to me. I kinda thought you were making an argument supporting "rocket catching."
Thanks for your clarification.
TH-
Thanks for the reminder; lots happening in the field and trying to keep focused is difficult at times.
I've been giving a lot of thought to the final composition and duties of the "labor force" in the 2 construction triads. It appears that Sierra Nevada Aerospace has been working on some new habs that I want to consider including in the mission. The amount of "construction" is a variable that we don't have any control over at this juncture,
I understand the pencil model argument. Unfortunately, Starship isn't a pencil, and weighs 100 tons and is 9 meters in diameter. It's basic physics and analytical mechanics at play. There is such a thing called Inertia and mass is involved. Moving a 100 ton spacecraft
instantaneously just isn't within the possible domain of physics as I understand things. Huge amounts of energy are required and in milliseconds time scale to keep things from ending in an RUD of the spacecraft AND the catching tower.
I consider the landing angle from the vertical as a "crabbing movement," and unfortunately the recovery needs to be instantaneous. It isn't likely that this problem will be solved anytime soon.
Robert-
Read GW's comments in post #1166. My argument is all about the response time and magnitude required of corrective forces available in milliseconds.
Robert-
I have a Private pilot certificate and many endorsements for High Performance and Complex aircraft. Before my 2018 heart attack, I was well on my way to getting both an Instrument Rating and a Commercial certificate. The problem facing catching an object of the mass of a Booster is the incredible side sectional area, and total wind pressure involved which can overwhelm any sort of controls. Tilting the rocket is essentially a "crab" into the relative wind. Control response time is too long for making a correction to vertical.
You make it sound simple--but it ain't.
There are some conflicting engineering issues involved with the "catch a rocket" system. Landing under dead calm conditions is not going to be possible very often, and as GW stated above in post #1166, there isn't any system (other than gas thrusters) available to compensate for being blown off center. The gas thrusters work well in space, but the wind forces near the ground exceed the ability and forces available to make corrections on a massive and large wind catching surface area rocket. If Elon wants this system, they will no doubt try to do it, but legs are cheaper and probably going to be the final solution.
GW-
The analysis of the landing of SN 15 proves your assertion about landing accuracy. It appears that a gust of wind blew it to near the edge of the landing pad and the so-called "landing legs" showed signs of horizontal shear, illustrative of the vehicle having a sideways movement vector on touchdown.
Just because there are animations showing how something COULD or possibly WOULD work, there's still a lot of engineering involved and lots of RUDs.
If Elon wants to get this "catch the rocket" system working soon, he may need to take some baby steps first.
GW is absolutely correct about the location of the CG of the Starship. The engines are by far the heaviest parts of the rocket and they are near the base. Everything else is empty sheet metal tanks.
The concept of using a "rocket catcher" sounds appealing--until looking at the problems that stand between success and failure. This almost violates Musk's own principles that, in a nutshell, are KISS. Four legs may have problems being incorporated into the existing designs, but they are known to work. If it ain't broke, don't fix it
I would say that the landing leg problem needs to be addressed soon, otherwise a lot of RUD hardware will be strewn about the landing area.
The tiles are not held on by adhesives, but are held by mechanical clips to internal metal structures.
I think that Musk is overly optimistic about catching the rockets; just MHO.
As long as Elon has money to keep funding the learning curve, they Will learn. SN 20 is the first one scheduled for an orbital flight. I hope they DO fly SN15 a second time, and finding out more about the heat shield tiles from a higher altitude flight which might give them a start on one of those other learning curves. SN 16 is probably going to fly before the month is out. Don't know what other "improvements" have been made in that SN.
The engine bay fire seems to be associated with insulation pads breaking loose and burning. There have been other online comments about the "popping" sound heard and being COPV's rupturing. Lots of "stuff" to be concerned about!
Musk Tweeted today that there is a possibility for SN 15 to fly again, and soon..
Mary, a.k.a. Bocachicagal, has an excellent view of the landing from the seaward side that is unobscured by the dust being kicked up by the Raptors.
This post-landing fire situation bothers me a LOT!
SN 15 is being moved this morning and is in the recovery phase. Now they can examine the plumbing to discover the source of the post-landing fires. It's great that they now can do a full post mortem on the recovered vehicle, and a lot more than they could from a pile of recovered junk.
I'm not sure the engine bells are slamming into each other. In order to do that, the gimbal system would have to be FUBAR. I think we're seeing the computer controlling them even though nothing is powering the rocket at the time.
The landing leg issue will undoubtedly be addressed soon; otherwise--more rapid unscheduled disassembly will occur.
Elon seems a bit stubborn about the leg issues, though.
Thomas-
There are many reasons that there will be someone "on duty" around the clock. Since the entire colonial expedition will depend on electric power, oxygen, and monitoring of radiation, there will be someone monitoring the nuclear reactor and oxygen levels constantly. There needs to be a "fire watch," in case something does get out of kilter. Out of 17 members of the expedition, at least 2, and possibly 3, will remain alert at all times. This should be a rotating responsibility and all members will have "night shift" on a rotating schedule.
To ignore the concept of equipment failure is irresponsible.
Identification of water ice isn't necessarily the problem, but finding easily extractable water is advantageous. That's where these skills are invaluable.
Geology Triad.
Hydrologist. Need this particular specialty for finding easily obtainable water and doing some seismic studies.
Stratigrapher. This is for determining which formations may yield fossils, and supports the work of hydrologist in finding water.
Minerologist. Finding usable minerals is extremely important for future development of Mars based industry.
Identification of water ice isn't necessarily the problem, but finding easily extractable water is advantageous. That's where these skills are invaluable.
All geologists will participate in seismic studies.
GW-
Some of the ideas that Elon has proposed do fall into the realm of Rube Goldberg devices, but Elon has a lot of wishful thinking dreams that he can afford to pursue. I'm skeptical that he can make landing the Super Heavy by catching it with his tower will work, but he seems to think that it's do-able. The hover-slam landings of Falcon 9 seems to be well-refined now, but as you commented about the increased weight of Starship and need for more than a single engine running at a time will probably just be another step on the learning curve for the SpaceX engineers.
P.S. added in edit: The landing legs concept on the Lunar Starship are still too narrow w/r to the height of the vehicle.