45 thoughts on “New From Casey Handmer”

  1. Somewhat interesting if you happen to believe Mars is the most important target AND that Starship will meet all cost/price and performance goals.

      1. Trust more than the legacies is somewhat different from buying the whole concept of thousands to Mars each synod.

  2. I think the first payloads should be Starlink satellites. That way they can provide comms and navigation all over the planet. This can allow few humans to then operate fleets of drones (next payloads) to begin harvesting of minerals and construction.

    1. Yes first Starlink satellites. But then surface PV solar arrays soon after? Or wait. What if instead we ship over self-assembling large PV arrays in GMO? (Geo-synchronous Mars orbit). For smaller power requirements that would stay operational for nearly 24’39″/~7 sols a week, except for the length of time the sat’s pass into Mars shadow? Thus getting night-time power when it is most desperately needed. Plus the added benefit that a microwave ground array rectifying antenna would be far less susceptible to dust & dust storms than a PV array. At least until there is nuclear available. Also one wouldn’t need GW scale SSPS, 1 to 10MW or so would do, so the scale ought to be considerably smaller making it more feasible.

      1. I wonder if GMO is outside the orbits of Phobos and Deimos? Have to research that. Might be another source of interference.

      2. As it turns out it’s only Phobos (figures!) as per Grok.

        Although my beam would be much smaller so maybe more likely to miss on a pass, since the longitudes & latitudes would have to align. Worst can in a complete eclipse, only a few seconds. With proper power regulation, needed for the longer solar outages anyway shouldn’t even be noticeable.

        Learned a new word today: aerosynchronous (as in Ares, the Greek word for Mars I suppose).

        Therefore it is Aerosynchronous Mars Orbit aka AMO.

        1. Why not go to Phobos instead of GMO.
          Why not mostly go to Phobos instead of Mars surface.

          Lack of gravity, and Mars has more gravity?

          1. Phobos lacks a lot of stuff Mars surface has. No atmosphere, so no carbon dioxide to run the fuel cycle with.
            ISRU is so much more efficient than sending fuel to Mars that it should more than make up for landing/liftoff energy.

          2. Our Moon in polar regions could have frozen CO2, Phobos polar region could have a lot less frozen CO2- instead millions it might have thousands of tons.
            In spots in the lunar polar region, one can get more sunlight as compared to anywhere else on the Moon. The same applies to Phobos.

        2. BTW just for the record, it’s Areosynchronous Mars Orbit not Aerosynchronous Mars Orbit…

          …I cannot sepll…

        3. My son had a question on a physics test last semester about putting “a 3500 kg spacecraft into geosynchronous orbit around Mars”. He messaged me about the question, knowing that I would be interested, and in his message he used the word geostat. I texted back, “Areostat!” He replied, “Staggeringly nerdy distinction. But interesting.”

      3. Staying focused on delivering power to Martian surface. Grok is telling me that with conversion efficiencies involved you’d need a PV array that can generate 5MW of power to deliver 1MW to the surface from AMO. That’s a square array of 178m on a side, large but doable, esp. if you make it out of a mosaic of smaller tiles. You’d need (again according to Grok I haven’t double checked the numbers) 1,296 5m squares (fits inside a Starship, (via Pez dispenser?) you could go bigger of course) in a 36×36 arrangement to get the desired size. So some assembly in orbit required. Why 1MW? Well here’s Grok’s final answer on how much electrical power it’d take to run the Sabatier process long enough to provide enough methane to load a Starship on Mars for a return trip to Earth:
        Final Answer
        To generate 100,000 kg of methane for a Starship Mars-to-Earth trajectory using the Sabatier process, you’d need approximately 4.5 GWh of electrical energy, translating to a continuous power draw of about 240 kW over 26 months. This assumes solar power and electrolysis as the hydrogen source, leveraging Mars’ CO₂-rich atmosphere. Scale up slightly for redundancy or a faster timeline—say, 300–500 kW with a 1–2 MW plant—and you’re in the ballpark of SpaceX’s vague 1–10 MW estimates for a full propellant depot.

        1. Grok is saying the Mars SSPS would suffer roughly the same outage period per sol as does one operating in GEO around Earth. About an hour per sol. You use either batteries or multiple SSPS’s to make up the difference. Obviously you could also use a nuke. But if you have nukes on Mars you don’t need the SSPS’es. I’m assuming the SSPS’es are boot-strap tech to get you started until the nukes arrive. But if SMR’s are on the scene first, that’d probably be the right way to go.

          Anyway it was an interesting “conversation” to have with Grok3.

          1. “Grok is saying the Mars SSPS would suffer roughly the same outage period per sol as does one operating in GEO around Earth. About an hour per sol.”

            GEO satellites do not suffer an outage period of about 1 hour per sol. For most of the year, GEO satellites are in sunlight 24 hours a day. The only exception is when the satellite flies through the Earth’s or Moon’s shadow, which is an eclipse. GEO satellites only are eclipsed by two things:

            1. The earth itself, but only for about 22 days before and after an equinox. This is known as the eclipse season. If the satellite is geostationary, the maximum eclipse time is 72 minutes on the day of the equinox. At the beginning of eclipse season, the outage is only a few minutes long. It gradually increases as the day of the equinox approaches, maximized on the day of the equinox, then decreases through the end of the season.

            2. Lunar eclipse: this can create an outage that lasts longer than an equinox but is much less common.

            For Mars, a lunar eclipse is unlike to be much of an issue. Mars will probably have its own version of eclipse season.

            https://news.viasat.com/blog/scn/how-satellites-are-affected-by-the-spring-and-autumn-equinoxes

          2. Thanks Larry. I did not extrapolate my experience with satellite internet with GEO SSPS, but I should have. In the case of satellite internet there was the “solar outage” that occurred for about 20 minutes twice a year at the equinoxes when the Sun passed behind the GEO satellite providing the service, disrupting its signal. I remember experiencing that directly back when I had satellite internet. So similar effect but due to a different cause.

            So alignment with Mars equinoxes aligns with the Martian calendar but not so much Earth’s calendar as expected. Once again here’s what Grok3 has to say about it:

            Mars’ polar inclination, or axial tilt, is approximately 25.19 degrees relative to its orbital plane. This tilt is quite similar to Earth’s, which is about 23.44 degrees, and it’s what gives Mars its seasons, though they’re longer due to its year being roughly twice as long as Earth’s (about 687 Earth days).

            As for the Mars equinoxes, they mark the points when the planet’s equator aligns with the Sun, just like on Earth, dividing the Martian year into its seasonal cycles. Since Mars’ orbit and Earth’s orbit don’t sync up perfectly, the exact Earth dates for Mars’ equinoxes shift year to year. However, I can give you a general sense based on recent cycles and the Martian calendar.

            Mars has two equinoxes: the northern spring equinox (start of autumn in the southern hemisphere) and the northern autumn equinox (start of spring in the southern hemisphere). For example, in 2024, the northern spring equinox on Mars occurred around May 23, and the northern autumn equinox was around April 8, 2025 (just a bit past today’s date, February 25, 2025). These dates slide forward by about 4-5 Earth days each Martian year due to the difference in orbital periods.

          3. “In the case of satellite internet there was the “solar outage” that occurred for about 20 minutes twice a year at the equinoxes when the Sun passed behind the GEO satellite providing the service, disrupting its signal.”

            That’s a different issue called sun intrusion or sun interference. That’s when the sun, the satellite, and the antenna align causing the high RF noise from the sun to overwhelm the satellite signal. When sun intrusion happens is depending on the receiver antenna’s location. It usually doesn’t happen on the equinox unless you just happen to live in that specific place. My experience with sun intrusion is that it usually lasts 5 minutes or so, but that also depends on the antenna’s beamwidth. The sun’s relative size is about half a degree and the Earth rotates 15 degrees per hour. If the antenna has a beamwidth of 3 degrees, the leading edge of the sun enters the beamwidth and the earth rotates it past the trailing edge about 4 minutes later. The sun is such a big RF noisemaker compared to the satellite signal that there may be some interference before and after the sun is within the antenna’s normal field of view.

            https://csinewsnow.com/wp-content/uploads/2015/03/solarout.png

          4. What’s interesting to me is that by putting the PV array into AMO you don’t have issues with night-time loss of power. That is if you are going to use solar electric to power a Mars base. This option seems to make more sense to me than a surface array. Also during eclipse season, if you place multiple SSPSes in AMO, spaced out across longitudinal orbital spots, you can switch between them during eclipse season to maintain continuous power or just use batteries to tide you over and not run the Sabatier converter during the low power times.

            If you have nuclear you have the cooling issue. But less infrastructure to build out if you just use a one-way Starship as a power plant which will also provide 24(.5)/7 power.

            BTW I don’t know if it will be 24.5/7 on Mars. Maybe with a 668.6 sols/year, Martians will want a 24 month calendar of 9 days a week for 3 weeks per month! OTOH I doubt that they’d want to go too radically different from Earth’s calendar just to keep dates straight!

        3. FYI I meant to say a 5m square fits within a Starship. It might take several Starships to deliver 1,296 of them.

    2. Yup, at least one Starship dedicated to deploying satellites. It could then be used to test their landings with no payload to explode.

  3. Better late than never (some of us saw all this 17 years ago, when Falcon 1 first made orbit), but he still doesn’t fully get it and he still hasn’t done his homework. China has a Starship clone under rapid development. They are the “fast follower” some people blat about. Starship is sufficient to build a colony on Mars. Just barely, but enough. Musk is talking about a 18-meter version. But first, he has to live through the next few years.

    1. If it had been up to me he’d stayed focused on SpaceX. But I presume he felt that it would become impossible to pursue his Mars goal unless he got involved in the government to keep them out of SpaceX’s business. The problem is, how to re-land in the private sector after a stint in DC making enemies? AP Headline in 10 years or so: “Musk flees to Mars to avoid prosecution, deportation.”

  4. Hasmer also has a case study looking to use a Starship to land a nuclear reactor on Mars.

    Turns out the biggest problem is heat dissipation. Assuming you land the Starship as a one-way delivery vehicle and use it as a free-standing power station once on Mars.

    I had always assumed you’d use something akin to the Boring Company’s digger to drill a shaft into the Martian soil to house the reactor with cooling loops running around under the surface to provide conduction cooling. But Hasmer thinks radiative cooling via the atmosphere is the way to go on Mars. Thing of it is, your radiative array ends up being about as big as would a PV array on the Martian surface to provide the same amount of power!

    He invents some novel scheme to run Martian air through the reactor to keep it cool.

    1. I think Musk also skips over the infrastructure part too much. There’s a lot to do just to get ready for extended stays on Mars before any people show up. I’ll give Zubrin credit for thinking much about that.

  6. “Phobos lacks a lot of stuff Mars surface has. No atmosphere, so no carbon dioxide to run the fuel cycle with.”
    It seems to be a carbonaceous chondrite so water and black stuff, likely carbon containing. So you have hydrogen, oxygen and carbon.

    1. But then you have taking that possible black stuff and converting it to something the Sabatier reaction machinery we send can handle. At least we know the Martian atmosphere’s composition.
      Also manufacturing in microgravity in general. Sending something only to find out it doesn’t work.

      I suppose it depends on what the plan is. The long term plan is mostly likely Mars settlement, not Phobos settlement, so why not go there in the first place? Power should come from something you can control. Handmer has some odd ideas like sending power to a lunar settlement from satellites. I wouldn’t want to settle anyplace where I can’t control the power my air comes from.

      1. Whoops, I was wrong about that sending power thing. Handmer’s idea was that because ground-based solar power is so cheap and reliable (he’s a big solar backer) any Earth orbital station should rely on ground-based solar beamed power instead of sending the extra mass to orbit of the solar panels…

        1. Seems to me just the opposite of what you’d want to do on Mars. If using PV arrays to power a base.

  7. Why Starship matters…

    FYI, this dropped from SpaceX yesterday on the root cause of the fire and subsequent termination of Starship Flight 7.

    The report also includes descriptions of mitigations employed for the next and future Starship flights. The need for a lot of this apparently may go away with Raptor V3.

  8. What is Elons opinons on nuclear power?

    Because I think it will be key to taming Mars.

    PVs are OK in space and on Earth but there a lot of dust on Mars and if it accumulates on the panels without anybody being around to remove it, you are dead.

    Plus they are heavy and require a lot of infrastructure.

      1. I was thinking of pulling Henry Spencer’s chain over on ARocket, saying Grok3 is like asking him a question over there. lol… Well, not quite….

  11. “Earth-Mars launch windows force these shipments to be stockpiled in Earth orbit and launched en masse every 2.14 years.”

    Launch early to get the best rates.

  12. Last I heard Elon is OK on nuclear power.
    As for what is on Phobos, we should go and find out or run the risk of missing some useful leverage.
    I can’t agree with Handmer on the whole climate change/need to not make CO2 etc. I don’t think any of his Earth based schemes will be economic. Juts build the advanced nukes we should have been working on for the last 50 years.

  13. Water on Mars is the first prerequisite. Minerals on Mars is an open question still. Minable thorium deposits? Because manufacturing PVPs on Mars is probably a doddle. Remember Musk saying its easier than making drywall? I hate drywall.

    1. Well since I’m fantasizing about SSPSes anyway. If that is really true, then you could do the Handmer alternative, which would be to place large panel arrays on the surface at various longitudes along the Martian equator and then drive power up to microwave reflectors in AMO which could relay power to any ground bases that are in night-time darkness. But I suspect power losses for a passive reflector would be too high to make that practical.

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