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Thread: Callisto colonization -- some crazy ideas

  1. #151
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    Particular papers with relevance to Callisto colonies, to be elaborated upon later.

    Callisto

    https://www.hou.usra.edu/meetings/lpsc2020/pdf/2703.pdf
    https://ui.adsabs.harvard.edu/abs/20....2703D/abstrac
    t
    INCLINATION DAMPING ON CALLISTO
    B. G. Downey and F. Nimmo
    Magnetometer data from Galileo flybys of Callisto indicate that Callisto has a subsurface ocean beneath an ice shell [1]. Given its orbital inclination of 0.19° and an expected comparable obliquity [2], there should be obliquity tides in the subsurface ocean. Energy dissipation in the ocean due to obliquity tides damps both obliquity and inclination since the two are connected [3]. [2] provides analytical expressions for the rate of energy dissipation in a subsurface ocean due to obliquity tides. Taking these rates and the inclinations of icy satellites in our solar system, we can approximate inclination damping timescales in Fig. 1. Callisto should damp its inclination in less than 1 Gyr, meaning that the inclination cannot be primordial. The question we address here is why does Callisto still have a non-zero inclination?

    https://ui.adsabs.harvard.edu/abs/20....149B/abstract
    Arecibo Radar Astrometry of the Galilean Satellites from 1999 to 2016
    Brozović, Marina, et al.
    Arecibo radar observations from 1992 provided some of the most precise line-of-sight distance (ranging) measurements of Ganymede and Callisto to date. We report 18 new ranges obtained at Arecibo from 1999 to 2016, among which are the first measurements of Io and Europa. We also report accompanying line-of-sight velocity (Doppler frequency) measurements. In 2015, we detected Europa, Ganymede, and Callisto with time-delay (range) resolutions as fine as 10 μs (1.5 km) while Io was detected with 70 μs (10.5 km) resolution. We estimated residuals for the radar measurements with respect to the latest JPL satellite ephemeris JUP310 and planetary ephemeris DE438. We found that the rms of the time-delay residuals are 29 μs for Io, 21 μs for Europa, 58 μs for Ganymede, and 275 μs for Callisto. When normalized by the measurement uncertainties, these correspond to the rms of 0.82, 1.25, 2.17, and 3.17 respectively. As such, the orbit of Callisto has the largest residuals and may benefit from an orbital update that will use radar astrometry. All Doppler residuals were small and consistent with their 1σ uncertainties

    https://ui.adsabs.harvard.edu/abs/20...2049C/abstract
    Dome Craters on Ganymede and Callisto May Form by Topographic Relaxation of Pit Craters Aided by Remnant Impact Heat
    Caussi, M.; Dombard, A. J.; Korycansky, D. G.
    The icy Galilean satellites host a variety of large impact features that are rare on other planetary and satellite surfaces in the Solar System. For Ganymede and Callisto, these features include impact basins with central pits and domes [1].Large complex craters on these two moons possess a central pit in place of central peaks seen elsewhere, and at larger crater sizes, these central pits host a dome (Fig. 1). The emergence of central dome craters occurs at diameters greater than ~60 km, which is also the approximate diameter at which central pit craters cease to occur [1]. It has been suggested [2, 3] that there could be a relationship between pit craters and dome craters. Understanding how these features formed can clarify our picture of outer-planet satellite evolution, and here, we focus on the formation of the central dome.

    https://ui.adsabs.harvard.edu/abs/20......7J/abstract
    Large Ocean Worlds with High-Pressure Ices
    Journaux, Baptiste; et al.
    Pressures in the hydrospheres of large ocean worlds extend to ranges exceeding those in Earth deepest oceans. In this regime, dense water ices and other high-pressure phases become thermodynamically stable and can influence planetary processes at a global scale. The presence of high-pressure ices sets large icy worlds apart from other smaller water-rich worlds and complicates their study. Here we provide an overview of the unique physical states, thermodynamics, dynamic regimes, and evolution scenarios specific to large ocean worlds where high-pressure ice polymorphs form. We start by describing the current state of knowledge for the interior states of large icy worlds in our solar system (i.e. Ganymede, Titan and Callisto). Then we discuss the thermodynamic and physical specifics of the relevant high-pressure materials, including ices, aqueous fluids and hydrates. While doing this we describe the current state of the art in modeling and understanding the dynamic regimes of high-pressure ice mantles. Based on these considerations we explore the different evolution scenarios for large icy worlds in our solar system. We conclude by discussing the implications of what we know on chemical transport from the silicate core, extrapolation to exoplanetary candidate ocean worlds, limitations to habitability, differentiation diversity, and perspectives for future space exploration missions and experimental measurements.

    https://ui.adsabs.harvard.edu/abs/20...0903S/abstract
    Ice Sheet Convection on Icy Moons
    Salinas, O. N.; Bassis, J. N.
    Geological activity and age variance between surface features on Europa, Enceladus, Callisto, and Ganymede suggest that ice sheets on icy moons are continually resurfaced by thermal convection. We can ascertain when these ice sheets convect at different rheological properties and compare them to ice sheets on Earth, which do not convect. Thermal convection is determined by the dimensionless Rayleigh number, the ratio between viscous and buoyant forces in a fluid. Localized thermal expansion leads to thermal convection in ice sheets when the upper boundary of an ice sheet layer is heated from below by subsurface fluids in its lower boundary. Changes in density within the ice sheet caused by thermal expansion introduce buoyancy forces that cause the colder, denser upper boundary ice to sink and the lower boundary ice to rise. Viscous drag resists the movement caused by buoyancy forces, and when the buoyant forces are stronger than the viscous forces, ice sheet convection occurs. The critical Rayleigh number marks the ratio between viscous and buoyant forces at which convection begins to occur, and Rayleigh number values higher than the critical value signify convection. We found the critical Rayleigh number for ice sheets with mantle convection simulations based in FEniCS Project. The simulations demonstrate behavior between the upper and lower boundary of an ice sheet at different Rayleigh number values, and we determined that the critical Rayleigh number for ice sheets is 785. To compare the convection ranges between the moons and Earth, we plotted when ice sheets convect using a constant critical number and a range of rheologies. Our plots suggest that terrestrial ice sheets will convect at the lower end of viscosities used to simulate icy moon convection. Our data demonstrates how ice sheets convect on icy moons and do not convect on Earth at only specific rheologies. Since ice sheets on Earth do not convect, we suggest that only viscosities in the upper range of 1015─1016 Pascal/s be used to simulate icy moon dynamics.

    https://ui.adsabs.harvard.edu/abs/20...3477V/abstract
    Sensing the Endgame for Callisto's Ocean
    Vance, S., et al.
    We explore the possibility that Callisto's ocean sits beneath its high-pressure ice, rather than above it. Oceans perched between ice phases are considered to be stable configurations for Ganymede, Callisto, and Titan. High-pressure ices under the liquid water ocean will transport heat and solutes into the ocean as long as the convective adiabat for the ices remains close to the melting temperature (Choblet et al. 2017, Kalousova and Sotin 2018). However, this configuration may become unstable when the perched ocean is close to freezing and its salinity increases, if the ocean becomes denser than the underlying ice. Among the oceans in the solar system, Callisto's must be among the coldest and most saline because the internal heat appears to be low in the absence of tidal dissipation. Surface geology indicates its lithosphere is fully stagnant (Moore et al. 2004). Solid-state convection may continue beneath less than 100 km or dirty non-convecting ice (McKinnon 2006). And just below this layer may reside a liquid water ocean that is the lag deposit of Callisto's thicker primordial ocean, the concentrated result of 4 Gyr of freezing. Using representative interior structures based on the current constraints from the Galileo mission (Anderson et al. 2001 ) coupled with recently obtained thermodynamic data (Vance et al. 2018), we demonstrate the possibility for using magnetic induction to identify where the ocean currently resides in Callisto.

    https://ui.adsabs.harvard.edu/abs/20...3475C/abstract
    Lakes within Ceres: Can magnetic induction find water?
    Crary, F. J.
    Magnetic field measurements from the Galileo mission have established the existence of subsurface oceans within Europa, Callisto and possibly Ganymede. The signature is produced by the time-varying background magnetic field (due to Jupiter's tilted dipole field and rotation), which induces currents within the conductive, subsurface ocean. This technique has been suggested as a means of detecting oceans within other potential "water worlds." One potential application is the detection of subsurface water within the asteroid, Ceres. Ceres has also been identified as a potential water world despite its small size. It has geologically young features interpreted as evaporative deposits and there is evidence of weak water vapor outgassing. These observations suggest the presence of liquid water within Ceres. If so, the ocean may not be global. Some models suggest the presence of lakes produced by impact melting. Unlike the Galilean moons of Jupiter, the background magnetic field at Ceres is not a periodic signal from a planet's rotation. The time varying magnetic field is due to stochastic variations in upstream solar wind. The resulting induced field may be described by the frequency spectrum of the background field and a transfer function which depends on the properties of electrically conductive material within the body (e.g. a saline ocean or lake.) Using representative measurements of the solar wind, we present the spectrum of the inducing field and the induced signature from plausible oceans or lakes within Ceres.

    https://ui.adsabs.harvard.edu/abs/20.....04V/abstract
    Hydrothermal Activity in the Solar System's Ocean Worlds
    Vance, S.; Melwani Daswani, M.
    Evidence from spacecraft data indicates hydrothermal activity most compellingly in the planet Mars and Saturn's moon Enceladus. The current understanding of the duration, extent, and underlying geochemistry of this hydrothermalism is poorly constrained. In the solar system's extant ocean worlds—Europa, Ganymede, Callisto, Enceladus, Titan, and possibly Triton and Pluto—the potential for continued hydrothermal circulation and water-rock chemistry creates the prospect for long-term redox disequilibria that might provide the energy needed for life. However, in the absence of large-scale tectonic activity, the available supply of rocky substrate must be determined when the planet or moon forms, and the extent of reaction must be limited by the depths to which fluids can percolate into the rock (Vance et al. 2016). Geophysical forward modeling, incorporating improved geochemical data, provides a way to constrain possible paths in the geochemical evolution of potentially habitable worlds, and the consequent chemical and geophysical signatures of those different paths that might be measured by planned spacecraft missions (Vance et al. 2018).
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  2. #152
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    Quote Originally Posted by Roger E. Moore View Post
    https://ui.adsabs.harvard.edu/abs/20...1598S/abstract
    Interior Structure Models Suggest a Cometary Origin for the Large Icy Moons
    NOTES: Mining possibilities are high with the introduction of complex organic compounds and metals in upper crusts, in both Ganymede and Callisto, if carbonaceous chondrites are present from cometary impacts.

    https://www.hou.usra.edu/meetings/lpsc2020/pdf/2264.pdf
    REGIONAL POWER SPECTRAL ESTIMATION WITH APPLICATION TO GALILEO DATA OF GANYMEDE
    NOTES: Finding a way to utilize Ganymede's magnetic field as a human colony's protection from cosmic radiation (and Jupiter's radiation) would be excellent. If the magnetic field of Ganymede can be improved, all the better.
    Do good work. —Virgil Ivan "Gus" Grissom

  3. #153
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    Quote Originally Posted by Roger E. Moore View Post
    Particular papers with relevance to Callisto colonies, to be elaborated upon later.

    Callisto

    https://www.hou.usra.edu/meetings/lpsc2020/pdf/2703.pdf
    https://ui.adsabs.harvard.edu/abs/20....2703D/abstrac
    INCLINATION DAMPING ON CALLISTO.
    "Callisto’s present-day inclination can be accounted for by an orbital resonance crossing 0.5 Gya." Callisto is still moving outward in its orbit around Jupiter, very slowly. More importantly, astroengineering projects should consider the effect that the internal ocean has on Callisto's orbit, and should not interfere with that in a destructive way.
    Do good work. —Virgil Ivan "Gus" Grissom

  4. #154
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    Quote Originally Posted by Roger E. Moore View Post
    Callisto

    https://ui.adsabs.harvard.edu/abs/20....149B/abstract
    Arecibo Radar Astrometry of the Galilean Satellites from 1999 to 2016
    There is a need for a spacecraft to measure the orbits of the Galilean moons, especially Callisto, to greater exactness.
    Do good work. —Virgil Ivan "Gus" Grissom

  5. #155
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    Quote Originally Posted by Roger E. Moore View Post
    Callisto

    https://ui.adsabs.harvard.edu/abs/20...2049C/abstract
    Dome Craters on Ganymede and Callisto May Form by Topographic Relaxation of Pit Craters Aided by Remnant Impact Heat
    Drilling into a dome crater to form living space would be a good idea, unless waste heat generated by the colony melts the dome. A natural dome made of ice is an interesting feature to play with for colonies.

    One wonders what could be done by covering a crater from its parapet walls with reflective or radiation-proof material, possible raising the temperature inside the crater itself for industrial or living purposes.
    Do good work. —Virgil Ivan "Gus" Grissom

  6. #156
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    Quote Originally Posted by Roger E. Moore View Post
    Callisto

    https://ui.adsabs.harvard.edu/abs/20.....04V/abstract
    Hydrothermal Activity in the Solar System's Ocean Worlds
    Large worlds like Callisto are not geologically or hydrologically static. It is possible that heat generated far beneath the surface of Callisto and other worlds like it could be enough to support native life, or human industry and colonies in the manner of geothermal energy.
    Do good work. —Virgil Ivan "Gus" Grissom

  7. #157
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    Quote Originally Posted by Roger E. Moore View Post
    Callisto

    https://ui.adsabs.harvard.edu/abs/20...3477V/abstract
    Sensing the Endgame for Callisto's Ocean

    https://ui.adsabs.harvard.edu/abs/20...3475C/abstract
    Lakes within Ceres: Can magnetic induction find water?
    Magnetic induction, either from the Sun or artificially produced, could detected saline (electrically conductive) seas and lakes beneath the surface of Callisto and other celestial bodies. Maps created as a result could determine the positions of future colonies and industrial sites.

    Also: Khurana, K.K., et al. (1998) Induced‐magnetic fields as evidence for subsurface oceans in Europa and Callisto. Nature 395:777–780.
    Last edited by Roger E. Moore; 2020-Mar-29 at 05:02 PM.
    Do good work. —Virgil Ivan "Gus" Grissom

  8. #158
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    Callisto

    https://ui.adsabs.harvard.edu/abs/20...0903S/abstract
    Ice Sheet Convection on Icy Moons
    Over long periods of time, the surface of Callisto and other ice worlds could move because of thermal convection far underground. How this works is unknown, but surface movement could distort measurements made by science instruments, meaning constant upkeep with laser rangefinders and GPS systems would be required to keep them straight.
    Do good work. —Virgil Ivan "Gus" Grissom

  9. #159
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    Oops, may have misunderstood previous papers suggesting that the surface of Callisto could move. Appears that convection occurs below the surface, not on it.

    https://ui.adsabs.harvard.edu/abs/20...3477V/abstract
    Sensing the Endgame for Callisto's Ocean

    https://ui.adsabs.harvard.edu/abs/20......7J/abstract
    Large Ocean Worlds with High-Pressure Ices
    Last edited by Roger E. Moore; 2020-Mar-29 at 04:50 PM. Reason: accidental double post
    Do good work. —Virgil Ivan "Gus" Grissom

  10. #160
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    Maybe Callisto has life of its own.

    https://arxiv.org/abs/1506.06600
    Polymerization of building blocks of life on Europa and other icy moons
    Jun Kimura, Norio Kitadai
    (Submitted on 22 Jun 2015)
    The outer solar system may provide a potential habitat for extraterrestrial life. Remote sensing data from the Galileo spacecraft suggest that the jovian icy moons, Europa, Ganymede, and possibly Callisto, may harbor liquid water oceans underneath their icy crusts. Although compositional information required for the discussion of habitability is limited because of significantly restricted observation data, organic molecules are ubiquitous in the universe. Recently, in-situ spacecraft measurements and experiments suggest that amino acids can be formed abiotically on interstellar ices and comets. These amino acids could be continuously delivered by meteorite or comet impacts to icy moons. Here, we show that polymerization of organic monomers, in particular amino acids and nucleotides, could proceed spontaneously in the cold environment of icy moons, in particular the Jovian icy moon Europa as a typical example, based on thermodynamic calculations, though kinetics of formation are not addressed. Observed surface temperature on Europa is 120 and 80 K in the equatorial region and polar region, respectively. At such low temperatures, Gibbs energies of polymerization become negative, and the estimated thermal structure of the icy crust should contain a shallow region (i.e., at a depth of only a few kilometers) favorable for polymerization. Investigation of the possibility of organic monomer polymerization on icy moons could provide good constraints on the origin and early evolution of extraterrestrial life.
    Do good work. —Virgil Ivan "Gus" Grissom

  11. #161
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    If we're going to try this with Enceladus, growing plants with its "water", try it with Callisto, too.


    https://arxiv.org/abs/2003.14131
    Enceladus Farm: Can plants grow with Enceladus' water? (Preliminary Report)
    Daigo Shoji
    (Submitted on 31 Mar 2020)
    Enceladus is a saturnian satellite that should have liquid water inside of it (subsurface ocean). Measurements and experiments on water plume from Enceladus have revealed that Enceladus' ocean contains several salts such as NaCl. On the Earth, salt in soil has become a serious problem for agriculture, and importance of salt-tolerant plants are indicated. In order to test the effect of Enceladus' water to terrestrial plant, by hydroponic, we tried to grow three salt-tolerant plants (ice plant, swiss chard and salicornia) simulating Enceladus' water (Enceladus Farm project). Using water with 0.33% NaCl and 0.4% NaHCO3, which is consistent with the observations of Enceladus, all plants could grow if they were germinated and grown with pure water until each plant had a few leaves. However, growth rate can be suppressed compared with the plants cultivated with pure water. Because our first test was performed with loose conditions, more works are needed to evaluate the effect of Enceladus' water to plant growth. However, in addition to the works to grow plants on lunar and martian grounds, Enceladus' water may be used to consider properties of plant from wider environment.
    Do good work. —Virgil Ivan "Gus" Grissom

  12. #162
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    Popular Mechanics rates the moons of the Solar System and... Callisto comes in #20. Idiots. To be fair, Titan is pretty awesome, and so is our Moon, but #20 ???!?!?!?!?

    https://www.popularmechanics.com/spa...-moon-ranking/
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  13. #163
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    Study Jupiter's gigantic magnetic field and radio emissions from Callisto with a telescope built into an equatorial crater on Callisto, where Jupiter is at the zenith.

    https://www.sciencealert.com/check-o...adio-telescope
    Last edited by Roger E. Moore; 2020-Apr-10 at 11:15 AM.
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    Put a submarine on Callisto? Yes, to search for life below the surface, in the underground ocean.

    https://www.sciencenews.org/article/...r-solar-system
    Do good work. —Virgil Ivan "Gus" Grissom

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    No two underground oceans are alike in mass, salinity, pressure, and temperature. Much investigation must determine the major differences in the underground seas of Europa, Ganymede, Callisto, and Enceladus.

    https://arxiv.org/abs/2002.01636
    Magnetic Induction in Convecting Galilean Oceans
    Vance, S. D. ; Bills, B. G. ; Cochrane, C. J. ; Soderlund, K. M. ; Gomez-Perez, N. ; Styczinski, M. J. ; Paty, C.
    February 2020
    To date, analyses of magnetic induction in putative oceans in Jupiter's large icy moons have assumed uniform conductivity in the modeled oceans. However, the phase and amplitude response of the induced fields will be influenced by the increasing electrical conductivity along oceans' convective adiabatic temperature profiles. Here, we examine the amplitudes and phase lags for magnetic diffusion in modeled oceans of Europa, Ganymede, and Callisto. We restrict our analysis to spherically symmetric configurations, treating interior structures based on self-consistent thermodynamics, which account for variations in electrical conductivity with depth in convective oceans (Vance et al., 2018). The numerical approach considers tens of radial layers. The induction response of the adiabatic conductivity profile differs from oceans with uniform conductivity based on the ice-ocean interface or the mean value of the adiabatic profile by more than 10% in many cases. In addition, we consider the generation of induced magnetic fields by oceanic fluid motions that might be used to probe the ocean flows directly (e.g., Chave, 1983; Tyler, 2011; Minami, 2017). Assuming turbulent convection (Soderlund et al., 2014), we find that these signals can dominate induction signal at low latitudes, which underscores the need for spatial coverage in magnetic induction investigations. Based on end-member ocean compositions (Zolotov, 2008; Zolotov & Kargel, 2009), we quantify the residual magnetic induction signals that might be used to infer the oxidation state of Europa's ocean and to investigate stable liquids within and under high-pressure ices in Ganymede and Callisto. Fully exploring this parameter space for the sake of planned missions requires electrical conductivity measurements in fluids at low temperature and to high salinity and pressure.
    Last edited by Roger E. Moore; 2020-Apr-10 at 09:47 PM.
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    3-D radar sounding will help us look below the surfaces of the big Jovian satellites.

    https://ui.adsabs.harvard.edu/abs/20.....1JS/abstract
    https://www.spiedigitallibrary.org/c...66.short?SSO=1
    3D radar sounder simulations of geological targets on Ganymede Jovian Moon
    Sbalchiero, Elisa ; Thakur, Sanchari ; Bruzzone, Lorenzo
    Abstract: Subsurface investigation of the Jovian icy moons is expected to disclose interesting information on the Jovian system. The Radar for Icy Moon Exploration (RIME) is the instrument in charge of characterizing the subsurface of the three icy moons Ganymede, Europa and Callisto. To provide a key for interpretation for the real acquired data, simulations of different possible scenarios on Ganymede are presented in this work. In this paper, we present an approach to performance analysis of RIME based on the 3D modelling and electromagnetic simulations of selected icy moon targets. These simulations are carried out using the Finite-Difference Time-Domain (FDTD) technique, which has been used in recent years to support radar sounder applications. In this work, we analyze in detail some interesting targets: 1) the dark terrain regolith, 2) the bright terrain dielectric profile, and 3) the grooved bright terrain. Our analysis is performed in two levels. First, the contribution of individual features is analyzed, varying their geometry and composition to understand how the measured fields vary accordingly. Second, a more realistic geological arrangement of a combination of subsurface features is considered. The results are very promising and indicate that the subsurface response is detectable in most of the cases.
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    Gorgeous artwork in a review of the 2003 plan to send humans to Callisto, mission outlined in detail.

    Concept for a Human Mission to Callisto in the 2040s
    Beyond Earthly Skies (blog)
    Saturday, May 23, 2015
    http://beyondearthlyskies.blogspot.c...-callisto.html
    Do good work. —Virgil Ivan "Gus" Grissom

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    What is wrong with this picture? It's beautiful, but look at it carefully.
    "Jupiter and Ganymede from Callisto" with U.S. astronaut in foreground on Callisto.
    https://www.missionjuno.swri.edu/Vau...4&t=1583865299


    2019-03-22 13:17 UT
    Submitted By: SteffanMacMillan
    https://www.missionjuno.swri.edu/jun...essing?id=6695
    Do good work. —Virgil Ivan "Gus" Grissom

  19. #169
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    Looks like Callisto and Ganymede have had their orbits perturbed by the second sun hiding behid Jupiter. That is, Callisto appears to be below one of Jupiter’s poles, Ganymede’s orbit is off too, sunlight is coming from above and a little to the left, but there appears to be a star behind Jupiter as well.

    Oh! Just noticed that the direction of sunlight on Ganymede doesn’t match the direction of sunlight on Jupiter. And there is the relatively minor “seeing stars in sunlight” thing. Probably more I didn’t notice. Yep, that’s a mess.
    Last edited by Van Rijn; 2020-Apr-12 at 04:37 PM.

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  20. #170
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    Quote Originally Posted by Van Rijn View Post
    Looks like Callisto and Ganymede have had their orbits perturbed by the second sun hiding behid Jupiter. That is, Callisto appears to be below one of Jupiter’s poles, Ganymede’s orbit is off too, sunlight is coming from above and a little to the left, but there appears to be a star behind Jupiter as well.

    Oh! Just noticed that the direction of sunlight on Ganymede doesn’t match the direction of sunlight on Jupiter. And there is the relatively minor “seeing stars in sunlight” thing. Probably more I didn’t notice. Yep, that’s a mess.
    Wonder if someone from Boeing did it. OW BURN

    Maybe a cut and paste job.
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  21. #171
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    Your brain apparently gets bigger in weightlessness and stays that way. This is bad as it can affect the optic nerve and eyeball, plus other issues. Would this be a problem in the low gravity of large moons, like the Earth's Moon or Callisto?

    https://www.msn.com/en-us/health/med...ys/ar-BB12Cd1y
    https://www.upi.com/Science_News/202...8391586876555/
    Last edited by Roger E. Moore; 2020-Apr-15 at 06:46 PM.
    Do good work. —Virgil Ivan "Gus" Grissom

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    When shipping materials to Callisto for the first colony base, consider folding up colony parts to save on space. This article on lunar colonization applies elsewhere, too.

    https://www.sciencedirect.com/scienc...76X?via%3Dihub
    Graphics: https://ui.adsabs.harvard.edu/abs/20....487D/graphics

    Highlights
    • The creation of settlements on the Moon is part of the paradigm of space exploration.
    • Universality and readiness of settlement modules provide their fastest habitability.
    • Expandable modules can acquire sufficient protection immediately after deployment.
    • A decrease in transport missions due to compact folding of modules is demonstrated.
    • The mission scenario shows the algorithm of multiple use of parts of space transport.

    Abstract: The article reviews the contemporary concepts of space habitats, focusing on the habitats’ mass, dimensions, and resistance to the space environment. The authors discuss a concept of constructing a multifunctional settlement on the Moon's surface that suggests sequential solutions for main problems of assuring habitability and operational versatility. Different aspects of the efficient algorithm for lunar colony development were analyzed, including the efficiency of payload delivery and a possibility for assuring proper protection of payload. The article describes the advantages of using the modular design and standard components that are delivered ready-to-use and enable the shortest time needed to provide primary habitability of the on-planet colony. It was suggested to use load-carrying deployable structures as standard pressure shells of the generic modules because of the ability of these structures to acquire sufficient protection properties and three-dimensional stiffness once deployed. The article presents a scenario that gives an understanding of the way of using the proposed space transportation systems with a step-by-step expansion of the colony's functionality. In conclusion, the authors assume that the compact folding of standard habitat modules’ pressure shells during delivery can result in fewer transportation missions.
    Last edited by Roger E. Moore; 2020-Apr-14 at 07:46 PM.
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    "In situ resource utilization (ISRU) increasingly features as an element of human long-term exploration and settlement missions to the lunar surface. In this study, all requirements to test a novel, biological approach for ISRU are validated, and an end-to-end mission architecture is proposed. The general mission consists of a lander with a fully autonomous bioreactor able to process lunar regolith and extract elemental iron. The elemental iron could either be stored or directly utilized to generate iron wires or construction material. To maximize the success rate of this mission, potential landing sites for future missions are studied, and technical details (thermal radiation, shielding, power-supply) are analyzed. The final section will assess the potential mission architecture (orbit, rocket, lander, timeframe). This design might not only be one step further towards an international “Moon Village”, but may also enable similar missions to ultimately colonize Mars and further explore our solar system."
    https://www.sciencedirect.com/scienc...694?via%3Dihub
    Graphics: https://ui.adsabs.harvard.edu/abs/20....216L/graphics

    Highlights
    • Synthetic biology can help to bind elemental silicon from lunar regolith simulants.
    • E. coli can be combined with magnetism to extract iron from lunar regolith simulants.
    • The mission architecture can be accomplished with currently available launchers.
    • A lander together with a rover is sufficient for multiple biological experiments.

    COMMENTS: This appears to be a major spacecraft with little robotic bulldozer helpers. The main craft has a biological "reactor" that can process materials brought to it and produce refined materials for use in constructing a space colony or industrial device. On Callisto, melting the materials would be relatively easy in a nuclear-warmed bioreactor. The degree of self-maintenance would be extraordinary but within reason.
    Do good work. —Virgil Ivan "Gus" Grissom

  24. #174
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    Thoughts on trying to get to Callisto (from somewhere away from Jupiter) and later leaving it (and Jupiter), adding fuel to the "stay on Callisto and move to-and-from the other moons" concept.

    https://crowlspace.com/?m=201610
    SpaceX ITS: Reaching the Moons of Jupiter
    October 15, 2016: Starflight

    "Flying to Titan will be easier than flying to the large Moons of Jupiter. As strange as that claim might sound, it’s based on the simple fact that an atmosphere as thick as Titan’s is a boon to space-travelers trying to shed excess speed. Plus Titan is held in its orbit by a lighter planet – Jupiter masses 318 times Earth, while Saturn masses 95 times.

    "To launch into a parabolic solar trajectory requires a delta-vee of at least 8.75 km/s from LEO, as already mentioned in the Titan discussion. If we arrive at the orbit of Callisto and have to shed sufficient speed to come to a halt relative to Callisto (orbiting Jupiter at 8.2 km/s) then the delta-vee is 21.65 km/s. To land on Callisto softly requires fighting its gravity to touchdown. The minimum is 1.73 km/s, but if we use the Apollo experience as a guide, we’ll need about 10-20% more. Call it ~2 km/s.

    "Using ITS Tankers as stages, it’s pretty easy to compute the number required for a given Spaceship payload and delta-vee. Even with 0 payload, not even 10 stages gets 19.4 km/s delta-vee. A Hohmann trajectory, which takes ~1,000 days to get to Callisto, can be done with a single Tanker as a booster, if we’re carrying just 100 tons. However landing – an extra 2 km/s delta-vee – requires an extra booster. ALternately a Tanker can be sent separately to supply the landing propellant on arrival, as the dry-mass of the Tanker is less, so there’s less fuel required for a given delta-vee...."

    ==========

    Change "Mars" to "Callisto" and assume you are sending stuff to other worlds from either Callisto or outer prograde moons, to other Galilean moons.

    https://arxiv.org/abs/1910.03829
    Autonomous Multirobot Technologies for Mars Mining Base Construction and Operation
    Thangavelautham, Jekan; Chandra, Aman; Jensen, Erik
    (Submitted on 9 Oct 2019)
    Beyond space exploration, the next critical step towards living and working in space requires developing a space economy. One important challenge with this space-economy is ensuring the low-cost transport of raw materials from one gravity-well to another. The escape delta-v of 11.2 km/s from Earth makes this proposition very expensive. Transporting materials from the Moon takes 2.4 km/s and from Mars 5.0 km/s. Based on these factors, the Moon and Mars can become colonies to export material into this space economy. One critical question is what are the resources required to sustain a space economy? Water has been identified as a critical resource both to sustain human-life but also for use in propulsion, attitude-control, power, thermal storage and radiation protection systems. Water may be obtained off-world through In-Situ Resource Utilization (ISRU) in the course of human or robotic space exploration. Based upon these important findings, we developed an energy model to determine the feasibility of developing a mining base on Mars that mines and exports water (transports water on a Mars escape trajectory). Our designs for a mining base utilize renewable energy sources namely photovoltaics and solar-thermal concentrators to provide power to construct the base, keep it operational and export the water using a mass driver (electrodynamic railgun). Our studies found the key to keeping the mining base simple and effective is to make it robotic. Teams of robots (consisting of 100 infrastructure robots) would be used to construct the entire base using locally available resources and fully operate the base. This would decrease energy needs by 5-folds. Furthermore, the base can be built 5-times faster using robotics and 3D printing. This shows that automation and robotics is the key to making such a base technologically feasible.
    Do good work. —Virgil Ivan "Gus" Grissom

  25. #175
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    Quote Originally Posted by Roger E. Moore View Post
    If we're going to try this with Enceladus, growing plants with its "water", try it with Callisto, too.


    https://arxiv.org/abs/2003.14131
    Enceladus Farm: Can plants grow with Enceladus' water? (Preliminary Report)
    Daigo Shoji
    (Submitted on 31 Mar 2020)
    Enceladus is a saturnian satellite that should have liquid water inside of it (subsurface ocean). Measurements and experiments on water plume from Enceladus have revealed that Enceladus' ocean contains several salts such as NaCl. On the Earth, salt in soil has become a serious problem for agriculture, and importance of salt-tolerant plants are indicated. In order to test the effect of Enceladus' water to terrestrial plant, by hydroponic, we tried to grow three salt-tolerant plants (ice plant, swiss chard and salicornia) simulating Enceladus' water (Enceladus Farm project). Using water with 0.33% NaCl and 0.4% NaHCO3, which is consistent with the observations of Enceladus, all plants could grow if they were germinated and grown with pure water until each plant had a few leaves. However, growth rate can be suppressed compared with the plants cultivated with pure water. Because our first test was performed with loose conditions, more works are needed to evaluate the effect of Enceladus' water to plant growth. However, in addition to the works to grow plants on lunar and martian grounds, Enceladus' water may be used to consider properties of plant from wider environment.
    And it's been tried with Mars as well, so try growing things with simulated Callisto materials.

    https://ui.adsabs.harvard.edu/abs/20...1201E/abstract
    The Mars Gardens: a comparison of the viability of plants grown in Martian simulant regolith and in a hydroponics system
    Eglin, A.; Guinan, E.
    Abstract
    Over the next few decades NASA and private enterprise missions, such as SpaceX-Mars, plan to send human missions to Mars with the ultimate goal of establishing a permanent human presence on this nearby planet. For a colony on Mars to be self-sustaining, it will be necessary to provide food by growing plants in sheltered and heated greenhouses. Due to the huge cost of transporting materials into space, it will be too expensive to transport growing medium from Earth to Mars. Therefore, the growing medium must already be abundant on the red planet. Research at Villanova University as part of the Mars Gardens Project has shown that it is possible to successfully cultivate plants in simulant Martian regolith. However there are many issues with the simulant soil that need to be remedied before it is suitable for agricultural applications. The Martian regolith must be stripped of perchlorates, which are harmful to humans. Also, organic materials, such as worm castings, must be added to the regolith to provide nutrients for the plants, as Martian regolith is inherently sterile. From our past experience, the clay-like properties of the simulant-regolith exacerbate problems such as root-rot, wilting, and root-growth deficiency. Because using regolith as the growing medium presents significant challenges, this study explores the use of hydroponics systems as an alternative to regolith-based agriculture. In a hydroponic system no soil is used and the plant roots are placed directly in a nutrient solution. Due to the ease of nutrient-absorption, the test plants grow larger and more quickly than their soil-based counterparts. A comparison of plants grown in Martian simulant regolith and a hydroponics system indicates hydroponics may be preferable for Martian agriculture. Future work will investigate methods of further optimization of the hydroponics system.
    Do good work. —Virgil Ivan "Gus" Grissom

  26. #176
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    How to get to Callisto and get around the Galileans... nuclear fusion drives.

    https://arxiv.org/abs/2002.12686
    Achieving the required mobility in the solar system through Direct Fusion Drive
    Giancarlo Genta, Roman Ya. Kezerashvili
    (Submitted on 28 Feb 2020)
    To develop a spacefaring civilization, humankind must develop technologies which enable safe, affordable and repeatable mobility through the solar system. One such technology is nuclear fusion propulsion which is at present under study mostly as a breakthrough toward the first interstellar probes. The aim of the present paper is to show that fusion drive is even more important in human planetary exploration and constitutes the natural solution to the problem of exploring and colonizing the solar system.
    Do good work. —Virgil Ivan "Gus" Grissom

  27. #177
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    Look for a beautiful topographic map of Callisto (and other large Galilean moons), with a radar map of Ganymede, in 2030 when JUICE gets to Jupiter.

    https://link.springer.com/article/10...67-019-00282-8
    The Ganymede laser altimeter (GALA): key objectives, instrument design, and performance
    Hauke Hussmann, et al.
    CEAS Space Journal volume 11, pages 381–390 (2019)
    Published: 21 October 2019
    The Ganymede Laser Altimeter (GALA) is one of the ten scientific instruments selected for the Jupiter Icy Moons Explorer (JUICE) mission currently implemented under responsibility of the European Space Agency (ESA). JUICE is scheduled for launch in mid 2022; arrival at Jupiter will be by end of 2029 with the nominal science mission—including close flybys at Ganymede, Europa, and Callisto and a Ganymede orbit phase—ending by mid 2033. GALA’s main objective is to obtain topographic data of the icy satellites of Jupiter: Europa, Ganymede, and Callisto. By measuring the diurnal tidal deformation of Ganymede, which crucially depends on the decoupling of the surface ice layer from the deep interior by a liquid water ocean, GALA will obtain evidence for (or against) a subsurface ocean in a 500 km orbit around the satellite and will provide constraints on Ganymede’s ice shell thickness. In combination with other instruments, it will characterize the morphology of surface units on Ganymede, Europa, and Callisto providing not only topography but also surface roughness and albedo (at 1064 nm) measurements.
    Do good work. —Virgil Ivan "Gus" Grissom

  28. #178
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    Space missions to Jupiter often include flybys of the Galilean moons, sometimes by gravity assists. There is so much to see and the sites are so close together, it is only logical to combine targets into one trip out. Examples include the upcoming NASA Europa Clipper and ESA JUICE.
    https://en.wikipedia.org/wiki/Europa_Clipper
    https://en.wikipedia.org/wiki/Jupite...Moons_Explorer

    The idea is relatively old.

    https://web.archive.org/web/20070108...AAS-03-143.pdf
    DESIGN OF A MULTI-MOON ORBITER
    S.D. Ross et al.
    February 7, 2003, 13th AAS/AIAA Space Flight Mechanics Meeting

    It makes sense when possible, then, to combine colonization efforts for two worlds at once: Callisto and fellow giant moon, Ganymede. The delta-vee requirements to get from one moon to the other are fairly low and reasonable to manage.
    https://www.reddit.com/r/space/comme..._solar_system/
    https://web.archive.org/web/20160316...om/SqdzxzF.png
    https://web.archive.org/web/20160404..._solar_system/

    Getting to the two moons by the Interplanetary Transport Network is a low-energy, long-term project that can put large payloads on wild routes around the Solar System. Propelled by ion engines or the like, cargo ships would slowly accelerate out of Earth orbit to arrive at Jupiter and vicinity years later for a bearable price.
    https://en.wikipedia.org/wiki/Interp...nsport_Network
    http://www.dept.aoe.vt.edu/~sdross/p...entist2006.pdf

    Two colony worlds for the price of one, plus a little more.
    Do good work. —Virgil Ivan "Gus" Grissom

  29. #179
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    Thumbs up

    Discovered an interesting megastructure devised to generate electrical power from solar wind. It's a Dyson-Harrop satellite. In addition to links describing it, I've fixed one of the illustrations showing it so it is clearer and easier to understand.

    https://en.wikipedia.org/wiki/Dyson–Harrop_satellite
    https://www.lpi.usra.edu/meetings/ab...0/pdf/5469.pdf

    My suggestion is to have one orbit Callisto in a polar orbit or, better yet, set up at the Jupiter-Sol L1 point, beaming its energy to a power station (or 20) on Callisto.
    ERROR: Forgot that Jupiter's magnetic field will turn aside the solar wind, so the L1 spot it will have to be.

    https://en.wikipedia.org/wiki/Lagrangian_point#L1_point

    Unfortunately, I have no idea where the L1 point is located between the Sun and Jupiter, as far as distance from either. Will puzzle it out eventually.
    Attached Images Attached Images
    Last edited by Roger E. Moore; 2020-Apr-20 at 02:59 AM.
    Do good work. —Virgil Ivan "Gus" Grissom

  30. #180
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    A discussion of how to land on and colonize Europa turns out to have great applications to doing the same on Callisto and Ganymede. Keeping a tunnel open from the surface to the deep ocean could be a lot of trouble, however, even on Europa.

    http://asi.org/adb/06/09/03/02/110/europa2-wkshp.html

    Moon Miners' Manifesto #110, November 1997
    Section 6.9.3.2.110.of the Artemis Data Book
    Europa II Workshop Report
    First Contact IV, Sept. 27, 1997
    by Peter Kokh, Mark Kaehny, Doug Armstrong, and Ken Burnside
    Last edited by Roger E. Moore; 2020-May-02 at 02:21 PM.
    Do good work. —Virgil Ivan "Gus" Grissom

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