Europe’s Trace Gas Orbiter detects clouds over Martian volcano

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Europe’s Trace Gas Orbiter (TGO) has detected clouds over the western slopes of the giant Martian volcano Arsia Mons.

This is not a new discovery, merely a confirmation of many past observations, all of which suggest that water-ice glaciers once flowed down those western slopes, and that some of that ice remains trapped in underground caves and lava tubes there. Undeniably this region appears at present to be the most valuable real estate on Mars. It has caves where the first colonies can be more easily built. Those caves likely have water in them. And the location is near the equator, which is easier to reach and also makes the environment somewhat less hostile.

TGO is presently slowly aerobraking itself down to its planned science orbit, which it is expected to reach in 2018.


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  • Edward

    Undeniably this region appears at present to be the most valuable real estate on Mars. It has caves where the first colonies can be more easily built. Those caves likely have water in them. And the location is near the equator, which is easier to reach and also makes the environment somewhat less hostile.

    This may be so. In his Reddit session yesterday Musk suggested that “Landing site needs to be low altitude to maximize aero braking, be close to ice for propellant production and not have giant boulders. Closer to the equator is better too for solar power production and not freezing your ass off.

    However, the terrain surrounding Arsia Mons seems to be higher in altitude rather than lower. Unless they overcome the reliance on aerobraking, this may not be an early choice for SpaceX to land on Mars.

    I have no doubt that eventually the colonists of Mars will find methods for landing on the planet that allow for relatively efficient landings almost anywhere.

  • Edward: The question to be considered is a cost-benefit balance. If we know the western slopes of Arsia Mons have water and caves, that advantage could easily outweigh the need for a low altitude site to maximize aerobraking. In fact, I am sure of it, since any engine designs SpaceX or others develop to more efficiently overcome Earth’s gravity well are going to work real well in the lower Martian gravity.

  • Max

    The Caldera of Olympus mons is 50 miles across and 30 miles wide, nearly outside the Martian atmosphere. Only 13% of 7 mbar of Mars normal. A landing there would be totally by rocket thrust.
    The upside is it’s location near the equator, less fuel needed to reach space. More solar radiation for solar panels.
    The downside is this region of Mars is very dusty, landscape and rocks covered by powder. Lava rocks are generally very sharp and hazardous to maneuver. Space suits will need to be tough. One cut and your dead. Equipment will wear down quickly, or get stuck in the powder / volcanic pumas / or cinders. Lava tubes might be problematic to seal and possibly hundreds of miles from other Martian curiosities. The base of the volcano is as large as the state of Arizona, A person could take their entire life just to explore this one volcano.
    In short, a great location, with caves for shelter, for a science mission to study the volcano, but not a good location for a Mars base of operations.

    I would vote for a location that has plenty of water / carbon dioxide to make fuel and to support life with leisure. (in a harsh environment, pleasantries will make a large difference in the success of a martian colony)

    A base near the north pole will not only provide most of the necessities in large quantities, it could also shield the rocket from wind, like landing in a crater.
    The difference in temperature is about 70° Colder but both areas are still colder than Antarctica. Heat will be a problem that solar panels could never supply enough power for. Plutonium batteries will provide enough heat, and supply power for the base, melt caves in the water ice, and make fuel for the Rockets.
    The glacier will be covered with meteorites for study and construction materials. The landscape away from the polar ice cap Is mostly dunes, boring but not hazardous.
    Once reliable methods are proven, and life becomes self substaning, a second base at the Southern Hemisphere in the larger carbon dioxide ice cap will be easy to establish. Between the two bases, redundancy is the best protection for explorers across the planet. I picture large hydrogen Zepplin’s will be the best transportation.

  • LocalFluff

    Bob likes caves. That’s why he wanna see a Volcano landing site. :-)
    Putting humans into a low gravity vacuum lava tube that formed billions of years ago with no geological activity until some cavers enter, will likely not be on the menu for any explorer once there.

  • Tom Billings

    I would differ with Local and Max. In fact, lava tube caves are excellent places to settle when you are starting out off the Earth. Lava tubes are stable compared to anything explorers are going to do to them, since they have lasted billions of years already. Sealing lava tubes is not an unsolved problem, and can be done with In Situ materials.

    Use the water to generate Hydrogen along with your Oxygen propellant. Use the Hydrogen to reduce the large amount of Iron Oxides in the martian surface dust. Regenerate the water from that reduction of oxides into more Hydrogen and Oxygen by more electrolysis. Use the Iron dust powder in an electrostatic accelerator to coat (at about 5-10 km/sec) the inside of the lava tube caves. Use the already detected Nickel on Mars to generate similar powder and seal off the Iron coating (around a centimeter thick) with a Nickel coating that will not corrode in an Oxygen atmosphere.

    Since the area has water, and Arisia Mons has heat, the ability to survive there is formidable compared to other areas of Mars. Remember that while the peak of Arisia Mons is 20km above the average terrain of Mars, most of its lava tubes will be at far lower altitudes. The spread of a shield volcano like these happens *because* lava tubes are its main vents, and you will thus find many lava tubes that fed the growth of Arisia Mons at its base, …unlike the situation of Olympus Mons that Max used for his example, which has an extreme scarp around its base.

  • Edward

    You wrote: “Edward: The question to be considered is a cost-benefit balance.

    True, but we may differ in our expectation of the early exploration of Mars. So far, we have focused our probes on finding signs of life, and recently have looked for signs of past and present water as a means of supporting that search for past or present life.

    As we plan for manned missions, my expectation is that we will focus on the easier landing areas. Flat, lower level regions may be the preferred early exploration locations, especially as we learn how to operate on Mars. We will want to search for subterranean water that a well can reach and sustainably pump. If that does not pan out, then I expect that we will search in other areas and in the meantime target more exploration near the polar regions where we are sure water can be mined. Even if the lower areas do pan out, then I expect that the other areas will quickly become targets for exploration.

    I think that Robert Zubrin’s Mars Direct idea is the most cost effective method for early manned exploration of Mars. SpaceX’s announced plan and the story “The Martian” use variations on that method.

    If terraforming is in Mars’ future, colonies at the lowest altitudes would not be favorable, as future liquid water would form seas in those locations. For this case, near-distant future exploration can occur anywhere, but future colonization needs to be careful where it locates. An ideal location for an early settlement could turn into a river, lake, or ocean in a few hundred years. Thus Musk needs to find high ground where he can start the colony that he wants to eventually move to. Maybe that will be near Arisia Mons, as the surrounding area is fairly high.

  • Max

    For aerobraking, Hellas Planitia is a impact basin 23,500 feet deep. Deep enough that the air pressure there allows for liquid water at 35° F. Nearly everywhere else on Mars, ice turns directly into a vapor like carbon dioxide does here on earth. (At one atmosphere)
    Mars is too small to hold enough atmosphere to ever be warm. We could double its thickness by melting the southern ice cap. :-( The solar wind would blow it away as fast as we melt it. So no problem with open lakes and rivers… Unless we figure out a way to increase the mass of Mars, and to keep the nights warm, there will be no open liquid water on Mars.

    I have enjoyed three different caves in a lava flow in southern Utah. You are climbing up-and-down over sharp boulders as much as traveling forward. I’m not saying that lava tubes on Mars isn’t a good idea, the preparation and the safety factor may make it unreasonable. Traveling over rough terrain is not easy on earth, The equipment needed will be bulky and heavy adding to the cost of the mission. Moving suited people and equipment down hundreds of feet or so in to the lava tube means bringing elevator type equipment to the scene. (Unless a horizontal shaft or path is available… A job for a ultra light UAV in the future Mission) The rough texture of the lava cave will need to be ground down and shaped, debris on the floor moved to lay a foundation similar to concrete for level living arrangements in the habitat. The mining equipment will need to be liquid cooled because there is no air. Large pressurized tanks to hold the oxygen and hydrogen rocket fuel will need to be used as generator fuel to power the heavy equipment. The tank farm will be located outside of the living apartments or cave system due to safety concerns. Expect heavy wear and tear, breakdowns will be often. Replacement parts are years away, assuming that dozens of rockets with heavy lift capability are sent to Mars for this purpose. (Most likely 3-D construction machines will be used so that the colony will be self-sufficient making their own parts) Raw materials will be a primary concern. Without trucks, those materials must be on the volcano.

    The north pole, on the other hand, is just Sand and ice. Smooth bore man-made caves can be constructed by nothing more than a hot plutonium battery. Placed on a Mars rover it can even be mechanized for automatic operation for a pre-design floorplan. Long hoses and cables will not be necessary. Breakdowns will be a few, but raw materials will be plentiful. To collect nickel metal meteorite fragments, all you need is a rover dragging a permanent magnet. (done in combination with a belt that touches the ground then lifts to a container where the magnet is removed from the belt and the metal drops in the compartment, it could collect hundreds of pounds of metal a day with no human involvement while a metal detector locates and marks possible large deposits) ( I might mention that the tracks left behind will be erased by the wind, pleasing those who think we are destroying the pristine surface of Mars)

    Flat ground for the landing, minimal risk, plenty of resources, Break downs minimal, robotic intervention maximized for best results. Large safe living quarters with no debris’s or dust to deal with. Melted sand to form fiberglass or removing carbon from the air mixed with water making insulating foam, can be sprayed on the walls before Tom Billings metal treatment is applied.
    Manufacturing center will be created in a very short time making all the necessary heavy equipment to explore the surface including the volcanic lava tubes.
    None of this is easily done in volcanic terrain. Taking baby steps will pay off in the long run… Especially if there is a disaster, funding will dry up quickly. Once a viable thriving colony is established, it will never be abandoned like we did the moon for 50 years.

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