I still think you want to select the lower areas. More CO2 pressure, more atmosphere for water extraction from the atmosphere.
All good points. The reason I used Olympic Mons as an example is it pretty much illustrates an extreme. Another extreme could be landing at the pole where most of the ice in the world is located. At the poll you have a lot of the resources you’re looking for but you obviously have a large number of drawbacks.I’m not convinced that the thin air at the top of Olympic Mons is not an advantage for landing as opposed to a disadvantage.To land on Olympic Mons mostly it’s the same retro propulsive EDL the difference is at a certain point you will use your available lift to put the vehicle in a climbing arc. Near the top of this arc you will need to be near your intended landing zone.
Olympus Mons is a high basaltic desert, hard to land on and with few resources. Hellas is well below the Mars datum, Marineris Vallis is low and misty, the Northern Plains are icy and the poles are ice(s). All of the latter are better options!
I expect we will land folk at Olympus Mons, or they will trek there, but not for a while.
I used to be a Hellas Basin guy, but now I've converted to Valles Marineris, particularly Melas Chasma. Very deep, -5km. Has water in a couple different forms, both hydrated sulfates and nearby reoccuring linea. It has tall hills sticking up off the plane but still low craters and also a lot of flat area to land and build on. And it's not too far from high altitudes (+3km? +5km?) since it's near the cliff walls of Valles Marineris, so if you want thinner air for some reason, you're close to it. It's geologically interesting and has access to plenty of resources.And the view is incredible.
Quote from: Robotbeat on 06/12/2016 01:23 amI used to be a Hellas Basin guy, but now I've converted to Valles Marineris, particularly Melas Chasma. Very deep, -5km. Has water in a couple different forms, both hydrated sulfates and nearby reoccuring linea. It has tall hills sticking up off the plane but still low craters and also a lot of flat area to land and build on. And it's not too far from high altitudes (+3km? +5km?) since it's near the cliff walls of Valles Marineris, so if you want thinner air for some reason, you're close to it. It's geologically interesting and has access to plenty of resources.And the view is incredible.Could. Not. Agree. More. Especially with your selection criteria which I believe is close to Musk's criteria for his base.Including the last one. You want people motivated to stay. The Northern Highlands are rich in water, etc. resources but are mostly featureless landscapes.Thinking ahead to late 21st century, a narrow offshoot canyon site with adjoining walls would be great for initial "roof over the whole thing" settlement expansion. Gonna need lots of living space for the numbers of folks he talks about.
What about the North pole?-continuous sunlight for 220 days - increasing PV output, saving battery mass, and getting a lot more bang for your buck from energy systems over the 6 month long summer.-communications with earth and other space craft all the time-Lots of frozen CO2 and almost certainly H2O available (potentially in large quantities underground) - making processing for fuel and water easier as don't have to waste energy on compression. Large quantities of water enable substantial nuclear reactors - poles could be a good source-Can use ice for radiation shielding (easier to dig into or move, and possibly even liquefy and pump unlike rock)-Relatively low elevation.-Very little dust or wind-Possibility of making ice runways for winged planes, spaceplanes, (atmospheric augmented ramjets?) to land on or take off from at high speed.downsides might be boring and difficult to propulsively land on frozen CO2
Hasn't Acidalia Planitia or the Schiaparelli Crater been discussed before? I'm new to this specific thread, so let me know if these places have already been covered.
What about the North pole?-continuous sunlight for 220 days - increasing PV output, saving battery mass, and getting a lot more bang for your buck from energy systems over the 6 month long summer.-communications with earth and other space craft all the time-Lots of frozen CO2 and almost certainly H2O available...downsides might be boring and difficult to propulsively land on frozen CO2
I see caves mentioned frequently as good locations for initial Mars settlements. And there's a problem with that idea.Most caves on Mars, at least the ones we've been able to identify, are evacuated lava tubes. They're located on the great Tharsis lava sheets, which cover a good quarter of the planet.As near as anyone can tell, the Tharsis volcanism period occurred after the early, wetter Noachian period. While not bone-dry, these lavas were not overlain at any obvious point with glaciers or significant bodies of water.So, while Martian lava tubes can provide natural radiation protection, they tend to be found almost exclusively in big, boring sheets of basalt that don't have much in the way of ice or water deposits, either frozen into the regolith or in big buried glaciers.There will be trade-offs, but I think it's easier to dig into the ground for radiation protection where there is more water, than it is to go any appreciable distance to find abundant water and transport it back to your safe-but-dry lava tube...
Quote from: the_other_Doug on 06/13/2016 06:09 pmI see caves mentioned frequently as good locations for initial Mars settlements. And there's a problem with that idea.Most caves on Mars, at least the ones we've been able to identify, are evacuated lava tubes. They're located on the great Tharsis lava sheets, which cover a good quarter of the planet.As near as anyone can tell, the Tharsis volcanism period occurred after the early, wetter Noachian period. While not bone-dry, these lavas were not overlain at any obvious point with glaciers or significant bodies of water.So, while Martian lava tubes can provide natural radiation protection, they tend to be found almost exclusively in big, boring sheets of basalt that don't have much in the way of ice or water deposits, either frozen into the regolith or in big buried glaciers.There will be trade-offs, but I think it's easier to dig into the ground for radiation protection where there is more water, than it is to go any appreciable distance to find abundant water and transport it back to your safe-but-dry lava tube... Not for initial settlements but very interesting for large settlements and cities. Analysis seems to be that they are very stable over millions of years. That would be the search criteria I'd put in, are there lava tubes near water sources? If there's a vision of really settling Mars, Lava tube cities are the only way to produce a pleasant environment on a human time scale.
Quote from: RobLynn on 06/13/2016 05:00 pmWhat about the North pole?...And a questionable pleasure of temperatures of -78 Celsius almost year-round.
What about the North pole?...
Quote from: gospacex on 06/15/2016 08:09 pmQuote from: RobLynn on 06/13/2016 05:00 pmWhat about the North pole?...And a questionable pleasure of temperatures of -78 Celsius almost year-round.low temperatures wouldn't be much of a problem given very low rates of convective heat transfer in thin atmosphere - and are easily insulated against - thick walls are a requirement anyway for radiation protection.
Low temps might be a real advantage through reducing size of radiators required to dissipate concentrated energy sources (saving a lot of cooling system mass), improving efficiency of electrical machinery and computers etc, storing cryogenic fuels for rockets and giving simpler options for some chemical processing jobs (only 50-70K above critical point for CO and O2)
Quote from: RobLynn on 06/17/2016 05:27 amQuote from: gospacex on 06/15/2016 08:09 pmQuote from: RobLynn on 06/13/2016 05:00 pmWhat about the North pole?...And a questionable pleasure of temperatures of -78 Celsius almost year-round.low temperatures wouldn't be much of a problem given very low rates of convective heat transfer in thin atmosphere - and are easily insulated against - thick walls are a requirement anyway for radiation protection.I'm more worried about people and machines doing outside work. Any Mars location, even equatorial one, is quite cold by Earth standards. Working in -78 C conditions while atmosphere freezes out into snow? Not much joy. QuoteLow temps might be a real advantage through reducing size of radiators required to dissipate concentrated energy sources (saving a lot of cooling system mass), improving efficiency of electrical machinery and computers etc, storing cryogenic fuels for rockets and giving simpler options for some chemical processing jobs (only 50-70K above critical point for CO and O2)Such wonderful conditions, ask yourself why we don't build datacenters and liquid O2 plants on South Pole of Earth?...
The cold of the north pole is, in fact, an advantage. PARTICULARLY if you can somehow exchange heat with the ground or the ice instead of just the air.
What about the North pole?-continuous sunlight for 220 days - increasing PV output, saving battery mass, and getting a lot more bang for your buck from energy systems over the 6 month long summer.
...we do build data centers near the North Pole in order to take advantage of the low temperature for cooling: http://www.cnet.com/news/facebook-turns-on-data-center-at-edge-of-the-arctic-circle/
By the way, if you have access to a plentiful low-temperature cold sink, your nuclear reactor can produce more power (and/or can be lighter) and needs less fuel to do so.The cold of the north pole is, in fact, an advantage. PARTICULARLY if you can somehow exchange heat with the ground or the ice instead of just the air.
Quote from: Robotbeat on 06/17/2016 01:51 pmBy the way, if you have access to a plentiful low-temperature cold sink, your nuclear reactor can produce more power (and/or can be lighter) and needs less fuel to do so.The cold of the north pole is, in fact, an advantage. PARTICULARLY if you can somehow exchange heat with the ground or the ice instead of just the air.Usually yes. A reactor usually runs at 200 - 230°C
I don't have a good mental picture of the proportions of Valles Marineris; are the walls going to block enough of the sky that solar power will be limited, or is the canyon/valley so wide that the cliffs don't loom huge from the middle?
Quote from: Hotblack Desiato on 06/20/2016 07:15 amQuote from: Robotbeat on 06/17/2016 01:51 pmBy the way, if you have access to a plentiful low-temperature cold sink, your nuclear reactor can produce more power (and/or can be lighter) and needs less fuel to do so.The cold of the north pole is, in fact, an advantage. PARTICULARLY if you can somehow exchange heat with the ground or the ice instead of just the air.Usually yes. A reactor usually runs at 200 - 230°CMore like 300°C
...SX have been sharing data with NASA on various subjects. I'd be surprised if they don't have access to most, if not all of NASA's mapping of these issues for Mars. Where you have 2 sites that are neck and neck I'd say the tie breaker will be which one can you land the most payload at.
Quote from: philw1776 on 06/12/2016 03:46 pmQuote from: Robotbeat on 06/12/2016 01:23 amI used to be a Hellas Basin guy, but now I've converted to Valles Marineris, particularly Melas Chasma. Very deep, -5km. Has water in a couple different forms, both hydrated sulfates and nearby reoccuring linea. It has tall hills sticking up off the plane but still low craters and also a lot of flat area to land and build on. And it's not too far from high altitudes (+3km? +5km?) since it's near the cliff walls of Valles Marineris, so if you want thinner air for some reason, you're close to it. It's geologically interesting and has access to plenty of resources.And the view is incredible.Could. Not. Agree. More. Especially with your selection criteria which I believe is close to Musk's criteria for his base.Including the last one. You want people motivated to stay. The Northern Highlands are rich in water, etc. resources but are mostly featureless landscapes.Thinking ahead to late 21st century, a narrow offshoot canyon site with adjoining walls would be great for initial "roof over the whole thing" settlement expansion. Gonna need lots of living space for the numbers of folks he talks about.Absolutely agreed in re Valles Marineris, except for one pesky problem: weather.Winds are strong and sometimes unpredictable in the whole Marineris rift valley system, there are frequent landslides and dustslides along the walls which increase the amount of dust in the air (a bad thing from a variety of aspects), and the thicker air comes with the price of far more frequent cloud and fog events.All of which makes access really dicey, and sunlight less reliable for both power and farming.Not insurmountable problems, but significant challenges. I wouldn't look for the first attempts at landings and colonies to add more challenges than are absolutely required, just for the sake of a really, undeniably great view...
Quote from: Vultur on 06/19/2016 06:31 pmI don't have a good mental picture of the proportions of Valles Marineris; are the walls going to block enough of the sky that solar power will be limited, or is the canyon/valley so wide that the cliffs don't loom huge from the middle?At its widest, the cliffs are below the horizon from the middle; though widths vary of course, especially in the side canyons. And there is often hilly terrain in the middle. An additional consideration is that 'blocking the sky' provides radiation protection.
Quote from: gospacex on 06/20/2016 12:53 pmQuote from: Hotblack Desiato on 06/20/2016 07:15 amQuote from: Robotbeat on 06/17/2016 01:51 pmBy the way, if you have access to a plentiful low-temperature cold sink, your nuclear reactor can produce more power (and/or can be lighter) and needs less fuel to do so.The cold of the north pole is, in fact, an advantage. PARTICULARLY if you can somehow exchange heat with the ground or the ice instead of just the air.Usually yes. A reactor usually runs at 200 - 230°CMore like 300°CI'm guessing you're talking about a PWR. That also needs a 200atm pressure vessel to hold it.
Quote from: john smith 19 on 06/21/2016 07:13 amQuote from: gospacex on 06/20/2016 12:53 pmQuote from: Hotblack Desiato on 06/20/2016 07:15 amQuote from: Robotbeat on 06/17/2016 01:51 pmBy the way, if you have access to a plentiful low-temperature cold sink, your nuclear reactor can produce more power (and/or can be lighter) and needs less fuel to do so.The cold of the north pole is, in fact, an advantage. PARTICULARLY if you can somehow exchange heat with the ground or the ice instead of just the air.Usually yes. A reactor usually runs at 200 - 230°CMore like 300°CI'm guessing you're talking about a PWR. That also needs a 200atm pressure vessel to hold it. That's only because of "no boiling" requirement.BWR go only a tad below 300°C (say 290°C) and they operate at ~70atm.
It was thermal 38MW. Little electric because the steam was directly used to drive the turbines for 7.355MW power engines.
SpaceX will follow the waterhttp://www.jpl.nasa.gov/spaceimages/details.php?id=pia20756
Hi folks, new to the thread but not the subject matter. In fact, I'm quite well-versed in it. Care to let the "newbie" chime in?
The "best" place depends as always on your goals.For NASA that may be more to do with "interesting" science locations. Bottoms of cliffs, deep ("high" atmospheric pressure) canyons, possible ice etc.For SX their end game is human settlement. ISRU is viewed as essential for their Methane based propellant system so water is also essential. Access to deposits of some other raw materials would be good (not sure which).
Of course, it's possible in many situations to extract water from hydrated minerals, as well, but it's energy-intensive, and nowhere near as easy as finding permafrost, or even relatively pure ice deposits. For an ample water supply, you're looking for ice, not just hydrated minerals. At least at first, anyway. And, of course, if it's possible to tap into a still-liquid system of briny aquifers that may yet exist on Mars, so much the better -- just dig some wells, and then treat the resulting water to remove the salts.
Along these find & follow the water ideas, SX needs to make orbital deep radar water ice surveying followed by ground truth validation high proirity
Quote from: philw1776 on 07/08/2016 01:24 amSpaceX will follow the waterhttp://www.jpl.nasa.gov/spaceimages/details.php?id=pia20756Right now, the Planetary Protection Protocols (PPP) would forbid landing at, or even approaching, any site where a liquid briny aquifer might be discharging to the surface. SpaceX will have to arrive at some kind of understanding as to how they are going to be respectful of the PPP and yet be able to find needful resources.
All good points. The reason I used Olympic Mons as an example is it pretty much illustrates an extreme.
Quote from: DAZ on 06/10/2016 11:33 pmAll good points. The reason I used Olympic Mons as an example is it pretty much illustrates an extreme.Olympus Mons?Water is a problemHABIT can be answerhttps://en.wikipedia.org/wiki/HABIT_(HabitAbility:_Brine,_Irradiation_and_Temperature)The HABIT instrument will use salts to absorb 5 millilitres of water from the atmosphere each day, and can hold 25 ml in total. If the process works as expected, the technology could be scaled up to provide water for future crewed missions.
Quote from: Lar on 06/11/2016 11:57 pmI expect we will land folk at Olympus Mons, or they will trek there, but not for a while.The trafficability of the Olympus slopes is an interesting thought. Little or no erosion on the shield portion, with gradually reducing dust deposits, and a slope measured in single figures of degrees. Cotton wool filled with a fractal razor blade surface? Walking might be challenging, but driving vehicles with *BIG* wheels might be practical. Remember, though, that the view will be far from spectacular en-route, though the caldera will be a hit, as will be the cliffs at the base of the mountain.
I always liked the looks of Elysium Planitia, 5° N, 150° E. Ash covered water ice? If you take a B+W photo of some of that area and reverse the values, what you get looks exactly like icebergs on Earth. Land between a couple of the "bergs" and tunnel into the side.Notice how the "bergs" break up as they flow around the craters in this picture:
Quote from: ThereIWas3 on 07/13/2016 06:36 pmI always liked the looks of Elysium Planitia, 5° N, 150° E. Ash covered water ice? If you take a B+W photo of some of that area and reverse the values, what you get looks exactly like icebergs on Earth. Land between a couple of the "bergs" and tunnel into the side.Notice how the "bergs" break up as they flow around the craters in this picture:You can explore this location at http://mars.nasa.gov/maps/explore-mars-map/fullscreen/The nearer of the two craters is at 5.63 N and 150.25 E. The image above seems to have been taken looking due South.Resolution is not the greatest compared to the pic but at least you can check out the neighborhood and the schools.
Quote from: philw1776 on 06/21/2016 03:48 pmAlong these find & follow the water ideas, SX needs to make orbital deep radar water ice surveying followed by ground truth validation high proirityThere is already near global MARSIS and SHARAD coverage. A higher frequency radar would give better mapping of near surface ice distribution, but it would only be an incremental improvement.
Is there a link somewhere to the final report and the criteria they used? The capabilities and goals of NASA's Mars assumptions in 2015 may be different from those of SpaceX in 2024.
Yes, but also more frequent fog and dust storms. A location with known reserves of water or other resources is more useful.
Thicker air is a help to parachute-aided landings, which have been NASA's only experience and probably what they were assuming for this sort of mission. But SpaceX has demonstrated hypersonic retropropulsion and bullseye landings quite convincingly and that opens up quite a lot more of Mars to consideration. Looking at those maps, most of the designated spots seem to be in the lowlands. Elysium Planita is in the equatorial highlands, where the water came from volcanic events. Estimates back in 2005 when that picture was taken were that the volume of water could be about the same as the North Sea on Earth. I pick water as the deciding factor for SpaceX's interests, followed by radiation shielding by cliffs, etc.
Thicker air is a help to parachute-aided landings, which have been NASA's only experience and probably what they were assuming for this sort of mission. But SpaceX has demonstrated hypersonic retropropulsion and bullseye landings quite convincingly and that opens up quite a lot more of Mars to consideration. ...
Quote from: Phil Stooke on 07/15/2016 06:37 pmYes, but also more frequent fog and dust storms. A location with known reserves of water or other resources is more useful. There are many RSLs seeping water indications in the valley. Plenty of resources & high atmospheric pressure.
Thicker air is a help to parachute-aided landings, which have been NASA's only experience and probably what they were assuming for this sort of mission. But SpaceX has demonstrated hypersonic retropropulsion and bullseye landings quite convincingly and that opens up quite a lot more of Mars to consideration.
SpaceX has demonstrated bleeding off 7km/s aerodynamically with Dragon. They intend to add propulsion to Dragon, too.
Quote from: ThereIWas3 on 07/15/2016 09:31 pmThicker air is a help to parachute-aided landings, which have been NASA's only experience and probably what they were assuming for this sort of mission. But SpaceX has demonstrated hypersonic retropropulsion and bullseye landings quite convincingly and that opens up quite a lot more of Mars to consideration.SpaceX has demonstrated getting a stage up to, what, somewhere between one and two km/sec? And then bringing it back down.Neither they nor anyone else has demonstrated bleeding off between 5 and 12 km/sec (depending on the speed of approach to Mars) purely aerodynamically, to get down to the quoted 1 km/sec the BFS will be able to handle propulsively, and then being within the needed navigation state to get to their target.Air density will definitely matter.
Dragon is kind of more analogous to what BFS will be doing. Orbital entry. And yeah, Dragon HAS demonstrated that. Hopefully it'll soon demonstrate propulsive landing after hypersonic reentry, too.
I'm guessing you're talking about a PWR. That also needs a 200atm pressure vessel to hold it. Most space nuclear reactor designs run considerably hotter and use a liquid metal heat pipe system for heat transfer. Such designs are much more compact and lighter (but then they don't generate the 100s of MW that PWRs generate. Realistically anything whose outlet temperature after power generation had been done is over 0c can be used to melt ice.