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tahanson43206,

If you have to carry the fuel and oxidizer with you, as you would on any planet except Earth, then pure Carbon doesn't require extra Oxygen atoms to combine with the Hydrogen atoms.

Kilograms of Pure Oxygen for Complete Combustion of 1kg of fuel:

Pure Carbon (32.8MJ/kg; 1kg powdered graphite = 1.05-1.15L; 28.52MJ/L): 2.67kg (2.34L); 3.49L ttl vol, 9.40MJ/L incl O2
Gasoline (44-46MJkg; 1kg = 1.2-1.4L; 32.86MJ/L): 2.3-2.7kg (2.37L); 3.77L ttl vol, 12.20MJ/L incl O2
Kerosene (43-46MJ/kg; 1kg = 1.25L; 36.8MJ/L): 2.93kg (2.57L); 3.82L ttl vol, 12.04MJ/L incl O2
Diesel (42-46MJ/kg; 1kg = 1.16-1.2L; 38.33MJ/L): 3.4kg (2.98L); 4.18L ttl vol, 11.00MJ/L incl O2
Methane (50-55.5MJ/kg; 1kg LCH4 = 2.36L; 23.52MJ/L): 4kg (3.51L); 5.87L ttl vol, 9.45MJ/L incl O2
Hydrogen (120-142MJ/kg; 1kg LH2 = 14.1L; 1L  = 10.07MJ/L): 8kg (7.01L); 21.11L ttl vol, 6.73MJ/L incl O2

LOX is 1,141kg/m^3 or 1.141kg/L

What can we conclude from that?

1. LH2 is a pretty pedestrian fuel when you need to store the cryogenic oxidizer, too.

2. There's not much difference between pure Carbon powder and Methane, except that making Methane is a lot more difficult and requires a lot more energy and technology than bubbling collected CO2 through a column of liquid Gallium eutectic.  You need equipment to collect both H2O and CO2, a Sabatier reactor, a reverse fuel cell, and a really good electrical power source.

3. You do get 17% to 30% more energy per total volume by combusting diesel / kerosene / gasoline, in comparison to Carbon powder, but if you thought making Methane was energy intensive, you're going to need to add a lot more energy-intensive equipment to your chemistry set, and of course, you only get that additional energy by combusting it using additional O2 mass, which means you need to make more O2 from some combination of H2O and CO2.  It's a pretty safe bet that all those additional chemical reaction steps will cannibalize whatever gains a dense liquid hydrocarbon fuel provides.

4. The relative complexity of obtaining LCO2 feedstock, on Earth or Mars, is pretty low.  It's everywhere in the atmosphere and in the oceans here on Earth.  Mars helps us out a bit by having a nearly-pure CO2 atmosphere, but at absurdly low density.  Speaking of absurdly low density, LH2 looks great, best of all fuels, except when you must consider the mass of the storage equipment, and then it doesn't look so hot.

5. Of all the fuels listed, and any other liquid hydrocarbon fuels that weren't, if you throw a kilogram of Carbon on the ground, here on Earth or on Mars, that same kilogram of pure Carbon fuel will still be there the next day.  We can't make the same claim about any of those other fuels.  Carbon doesn't require special storage of any kind.  If storing a cryogenic oxidizer is a pain we'd rather not deal with, then why compound the problem with fuels which also have special storage requirements?

Nice!  The idea of projecting upward is particularly interesting!  We could mount very light weight mirrors on the interior of the dome, and let the LED's projecting from below illuminate the entire interior.

The original idea was to mount panels on the interior wall, and that would have required lighting that would have needed cables to carry electricity, plus there would be need for periodic maintenance.  Your suggestion of projecting light upwards would eliminate all those issues.

or large-screen projection onto a wall, consider ultra short throw (UST) laser projectors which can create a massive, bright, 4K image from just inches away from the wall. For optimal image quality, especially in brightly lit rooms, pairing the projector with an Ambient Light Rejecting (ALR) screen is highly recommended.
Top Projector System Options
Here are some highly-rated projector systems suitable for large screens or walls:
Product Name     Throw Type    Resolution    Brightness    Key Features    Price Range (USD)
Hisense PX3-PRO    Ultra Short Throw (UST)    4K UHD    3,000 Lumens    Google TV, Dolby Vision, great for gaming    ~$3,000
Samsung The Premiere LPU9D    Ultra Short Throw (UST)    4K UHD    3,450 Lumens    Sleek design, smart capabilities with Alexa/Bixby, powerful built-in sound    ~$6,000
Epson EpiqVision Ultra LS800    Ultra Short Throw (UST)    4K PRO-UHD    4,000 Lumens    Android TV, Yamaha speakers, exceptionally bright picture in any lighting    ~$2,800
Optoma HCPro-4400    Standard Throw    4K UHD    5,000 Lumens    Dual laser, Dolby Vision/HDR10+, vertical/horizontal lens shift for flexible installation    ~$6,000
Key Considerations for Your Setup
Throw Distance:
Ultra Short Throw (UST): Sits a few inches from the wall, ideal for small spaces or living rooms where a ceiling mount or long cable run is impractical.
Short Throw or Standard Throw: Requires more distance from the wall but can be installed at an angle or ceiling-mounted, offering more flexibility in some professional or dedicated home theater setups.
Ambient Light: Projectors with high lumen ratings (e.g., 3,000+ lumens) and/or an ALR screen perform well in brightly lit rooms. A plain white wall works best in a light-controlled (dark) room.
Screen vs. Wall: While you can project onto a wall, an Ambient Light Rejecting (ALR) screen is engineered with specific materials to reject ambient light, enhancing color, contrast, and overall picture quality dramatically compared to a painted wall.
Resolution: 4K UHD and 4K PRO-UHD projectors provide stunning clarity and detail on large displays, making for an immersive viewing experience

For a large screen or wall projection system, key factors are high brightness (lumens), high resolution (4K recommended), appropriate throw distance, and a quality ambient light rejecting (ALR) screen.
Here is a guide and some recommended systems in BBCode format:
Guide to Choosing a Large Screen Projector System
To ensure a vibrant, clear image on a large scale (120 inches or more), especially in rooms with ambient light, consider the following specifications:
Brightness (Lumens): For large screens in a dark room, 1,500-2,000 lumens might suffice. For rooms with moderate to high ambient light (e.g., living rooms, conference halls with windows), aim for 3,000 to 6,000+ lumens. Laser projectors often provide more consistent brightness and longer life than lamp-based models.
Resolution: For large screen sizes, 4K resolution (3840x2160 pixels) is highly recommended to prevent the image from looking pixelated.
Throw Distance:
Ultra Short Throw (UST): Sits just inches from the wall/screen, ideal for smaller rooms and avoiding shadows.
Standard/Long Throw: Placed further back, often ceiling mounted, requiring more room space.
Screen Type: A quality Ambient Light Rejecting (ALR) or Ceiling Light Rejecting (CLR) screen is crucial for maintaining image vibrancy in well-lit environments, as a standard white wall or screen will look washed out.
Recommended Projector Systems
Here are a few high-performance projectors suitable for large screens (up to 150 inches), along with general screen guidance:
High-End Home Cinema (Standard Throw)
Epson Pro Cinema LS12000: A premium 4K Pro-UHD laser projector with exceptional color and contrast ratio, ideal for dedicated home theaters. It features extensive motorized lens shift for flexible installation.
Brightness: 2,700 lumens
Light Source: Laser (rated for 20,000 hours)
Screen Pairing: Pairs well with a high-quality 120"+ matte white or high-contrast screen.
Ultra Short Throw (UST) (for bright rooms/living areas)
Epson EpiqVision Ultra LS800: One of the brightest UST projectors available, designed to be placed near the wall. It's bright enough to be used in well-lit rooms and can produce an image up to 150 inches.
Brightness: 4,000 lumens
Light Source: Laser
Screen Pairing: Requires a specific UST/ALR screen for best performance in ambient light.
Hisense PX3-PRO: A triple laser 4K UST projector that supports Dolby Vision and is great for gaming due to low input lag in game mode.
Brightness: Approx. 3,000 lumens
Light Source: Triple Laser
Screen Pairing: Best used with an ALR screen designed for UST projectors.
Large Venue/Auditorium (Professional Grade)
Optoma ZU820T: A powerful professional installation laser projector designed for large venues, offering very high brightness.
Brightness: 8,800 lumens
Light Source: Laser
Screen Pairing: Suitable for very large screens (over 150 inches) in large halls or auditoriums where high ambient light is a concern.
When selecting a screen, consider brands like Elite Screens, Da-Lite, or Spectra Projection which offer various sizes and materials optimized for different projector types and lighting conditions

tahanson43206,

If you have to carry the fuel and oxidizer with you, as you would on any planet except Earth, then pure Carbon doesn't require extra Oxygen atoms to combine with the Hydrogen atoms.

Kilograms of Pure Oxygen for Complete Combustion of 1kg of fuel:

Pure Carbon (32.8MJ/kg; 1kg powdered graphite = 1.05-1.15L; 28.52MJ/L): 2.67kg (2.34L); 3.49L ttl vol, 9.40MJ/L incl O2
Gasoline (44-46MJkg; 1kg = 1.2-1.4L; 32.86MJ/L): 2.3-2.7kg (2.37L); 3.77L ttl vol, 12.20MJ/L incl O2
Kerosene (43-46MJ/kg; 1kg = 1.25L; 36.8MJ/L): 2.93kg (2.57L); 3.82L ttl vol, 12.04MJ/L incl O2
Diesel (42-46MJ/kg; 1kg = 1.16-1.2L; 38.33MJ/L): 3.4kg (2.98L); 4.18L ttl vol, 11.00MJ/L incl O2
Methane (50-55.5MJ/kg; 1kg LCH4 = 2.36L; 23.52MJ/L): 4kg (3.51L); 5.87L ttl vol, 9.45MJ/L incl O2
Hydrogen (120-142MJ/kg; 1kg LH2 = 14.1L; 1L  = 10.07MJ/L): 8kg (7.01L); 21.11L ttl vol, 6.73MJ/L incl O2

LOX is 1,141kg/m^3 or 1.141kg/L

What can we conclude from that?

1. LH2 is a pretty pedestrian fuel when you need to store the cryogenic oxidizer, too.

2. There's not much difference between pure Carbon powder and Methane, except that making Methane is a lot more difficult and requires a lot more energy and technology than bubbling collected CO2 through a column of liquid Gallium eutectic.  You need equipment to collect both H2O and CO2, a Sabatier reactor, a reverse fuel cell, and a really good electrical power source.

3. You do get 17% to 30% more energy per total volume by combusting diesel / kerosene / gasoline, in comparison to Carbon powder, but if you thought making Methane was energy intensive, you're going to need to add a lot more energy-intensive equipment to your chemistry set, and of course, you only get that additional energy by combusting it using additional O2 mass, which means you need to make more O2 from some combination of H2O and CO2.  It's a pretty safe bet that all those additional chemical reaction steps will cannibalize whatever gains a dense liquid hydrocarbon fuel provides.

4. The relative complexity of obtaining LCO2 feedstock, on Earth or Mars, is pretty low.  It's everywhere in the atmosphere and in the oceans here on Earth.  Mars helps us out a bit by having a nearly-pure CO2 atmosphere, but at absurdly low density.  Speaking of absurdly low density, LH2 looks great, best of all fuels, except when you must consider the mass of the storage equipment, and then it doesn't look so hot.

5. Of all the fuels listed, and any other liquid hydrocarbon fuels that weren't, if you throw a kilogram of Carbon on the ground, here on Earth or on Mars, that same kilogram of pure Carbon fuel will still be there the next day.  We can't make the same claim about any of those other fuels.  Carbon doesn't require special storage of any kind.  If storing a cryogenic oxidizer is a pain we'd rather not deal with, then why compound the problem with fuels which also have special storage requirements?

To move 10 cubic meters of Mars regolith, you would need a tandem axle dump truck or a medium-to-large single-axle dump truck. A standard commercial tandem axle dump truck typically holds between 7.6 to 10.7 cubic meters (10 to 14 cubic yards) of material, making it a suitable option for exactly 10 cubic meters.

Dump Truck Options for 10 Cubic Meters
Medium Dump Truck (Single Axle):
These can hold a load volume of 3 to 6 cubic meters, so you would likely need two trips, or a very large single-axle model near its upper limit.

Tandem Axle Dump Truck:
This is the most efficient option, as its typical capacity of 7.6 to 10.7 cubic meters can handle the entire volume in a single load. Some models can even handle up to 13 to 20 cubic meters.
Large Dump Truck (Tri-Axle/Super Dump): These trucks have capacities ranging from 13 to over 25 cubic meters, which would easily manage the load, though the truck might not be operating at full volumetric capacity.
Important Considerations

Weight vs. Volume:
The weight of the regolith (Martian soil) is a critical factor, even more so than volume. The density of material matters in determining the actual safe load capacity to avoid overloading the truck's weight limits.

Martian Gravity:
The user's prompt specifies "Mars regolith," which implies an off-world scenario. The lower gravity on Mars (roughly 38% of Earth's gravity) would significantly alter the weight constraints and potentially allow a standard Earth-rated dump truck to carry a larger mass of material than it could on Earth, assuming the engineering for the martian environment is addressed.

Equipment Specialization:
For actual off-world operations, the equipment would be specifically designed for the Martian environment, likely featuring wider cutting heads or different axle configurations to handle the unique terrain and gravity conditions.

Larger dump trucks can carry approximately 10 to 16 cubic yards of material. However, the total volume is not usually the limiting factor. In most cases, the vehicle’s weight limit will determine how much material you are ultimately able to safely transport.

A tri-axle dump truck typically weighs between 25,000 and 35,000 pounds when empty, but can weigh up to 80,000 pounds when fully loaded, depending on the load and local regulations. The specific weight varies based on the materials used to construct the truck (e.g., aluminum bodies are lighter than steel), the size and type of the dump body, and the weight of the fuel and driver

Oldfart1939 wrote:

I did a bit of research on the Bobcat website last night, and perhaps we should include 2 excavators (tracked backhoes). They're heavier and more bulky than the front loader Bobcat skid-steer units, but these would allow excavation of habitat shelter trenches more rapidly and effectively than front-loader units.

I see you're doing construction. Not just the first exploration/science mission, but construction. The Mars Homestead project assumed 12 crew to construct the first permanent human base. Yes, we believed a construction vehicle was required. I would like to make a suggestion.

This is a typical Bobcat skid-steer loader. There are various sizes. This one is S450. ("S" for skid) Rated Operating Capacity: 1,370lb. Operating weight: 5,370lb

The thing that makes it "skid-steer" is it's wheels. It's wheels don't turn, to steer the vehicle you turn the wheels on one side while wheels on the other do not turn. Or to pivot in place, turn wheels on the other side backward. This means the wheels literally "skid" across the ground as it's steering. Be advised: operating this on grass will tear up the grass. This works very well on pavement or hard or very firm ground. It doesn't work so well on loose soil/dirt/sand/gravel at an incline.

This is a typical Bobcat compact track loader. This one is T450. ("T" for track) ROC: 1,490lb. Operating weight: 6,424lb

Track vehicles work better on loose ground and inclines. The track provides more traction. I'm suggesting a compact track loader would be more appropriate for Mars.

An excavator can be compact. The first is E10, Rated Lift Capacity 527lb, Operating weight 2,593lb. The second is E20, RLC 1,098lb, Operating weight 4,306lb.
https://assets.bobcat.com/excavators/misc/r-series/bobcat-e10-nav_pm_list.jpg

Bobcat has become known for compact construction vehicles. Other brands manufacture competing vehicles: John Deere, Case, Caterpillar, New Holland, others.
Heavy Equipment Guide: Companies by Skid-Steer Loaders

Any vehicle would have to be customized for Mars. One suggestion I made was to manufacture the vehicle with titanium alloy instead of steel. Titanium has the same weight (mass), but greater strength. That allows making structural members like arms to lift the bucket thinner, so lighter. Hydraulics will have to be adjusted for extreme cold of Mars. And the engine can't breathe air, Mars has no oxygen. Well, practically none; not enough for combustion. When Robert Zubrin and David Baker proposed Mars Direct in 1990, they suggested using methane/oxygen because the ERV would need that for propellant anyway. Just make a bit more for the rover. But rather than using electricity to run ISPP, you could just operate the vehicle with electricity. At least one company specializes in electric conversion of Bobcat vehicles. And Bobcat themselves is working on all electric vehicles using lithium-ion batteries. They're even working on all electric actuators instead of hydraulics; intended for cold climates like Alaska.