Quote from: Vultur on 02/02/2016 12:37 amQuote from: Burninate on 01/31/2016 08:30 pmQuote from: Burninate on 01/31/2016 04:29 pmQuote from: BSenna on 01/31/2016 03:23 pmMaybe the "100 t payload" is the total land mass, a 60 t dry mass mct 25 t 100 people (+their goods and consumables) and 15t cargo or more cargo and less people. You engineering fellows, is that feasible with 3-4 refueling cargos?http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150003005.pdf offers 12 tons consumables budget for a 4-person conjunction-class (1030 day) Mars mission using closed-loop ECLSS. You're offering 25 tons for 100 people.How do the rest of you account for this?Depends on your assumptions for "closed loop".3 tons per person for ~1000 days isn't a very good closed loop. A person needs about 5 kg/day of life support consumables, so 3000 kg for 1000 days means you only save 40% with the closed loop... huh?Also, the MCT is probably carrying supplies for 100-250 days (depending on transit length) not 1000. Remember there are supposed to be ~10 cargo missions per crew mission (or something like that).As you can see in the joined graph (Ames research center trajectory browser), most synods offer 120 to 180 day missions to Mars. So if you do the math, you will find 52 tonnes of consumables for 180 days with 5 kg/person. As mentionned by others, you will only be having 100 passengers when there is a base in place, so the rest of the trip time is not applicable.To reduce to 25 tonnes you need to go to dehydrated foods, and do some fierce water and atmospheric recycling. But that equipement will be essential on Mars, so it should be part of a colony package.
Quote from: Burninate on 01/31/2016 08:30 pmQuote from: Burninate on 01/31/2016 04:29 pmQuote from: BSenna on 01/31/2016 03:23 pmMaybe the "100 t payload" is the total land mass, a 60 t dry mass mct 25 t 100 people (+their goods and consumables) and 15t cargo or more cargo and less people. You engineering fellows, is that feasible with 3-4 refueling cargos?http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150003005.pdf offers 12 tons consumables budget for a 4-person conjunction-class (1030 day) Mars mission using closed-loop ECLSS. You're offering 25 tons for 100 people.How do the rest of you account for this?Depends on your assumptions for "closed loop".3 tons per person for ~1000 days isn't a very good closed loop. A person needs about 5 kg/day of life support consumables, so 3000 kg for 1000 days means you only save 40% with the closed loop... huh?Also, the MCT is probably carrying supplies for 100-250 days (depending on transit length) not 1000. Remember there are supposed to be ~10 cargo missions per crew mission (or something like that).
Quote from: Burninate on 01/31/2016 04:29 pmQuote from: BSenna on 01/31/2016 03:23 pmMaybe the "100 t payload" is the total land mass, a 60 t dry mass mct 25 t 100 people (+their goods and consumables) and 15t cargo or more cargo and less people. You engineering fellows, is that feasible with 3-4 refueling cargos?http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150003005.pdf offers 12 tons consumables budget for a 4-person conjunction-class (1030 day) Mars mission using closed-loop ECLSS. You're offering 25 tons for 100 people.How do the rest of you account for this?
Quote from: BSenna on 01/31/2016 03:23 pmMaybe the "100 t payload" is the total land mass, a 60 t dry mass mct 25 t 100 people (+their goods and consumables) and 15t cargo or more cargo and less people. You engineering fellows, is that feasible with 3-4 refueling cargos?http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150003005.pdf offers 12 tons consumables budget for a 4-person conjunction-class (1030 day) Mars mission using closed-loop ECLSS. You're offering 25 tons for 100 people.
Maybe the "100 t payload" is the total land mass, a 60 t dry mass mct 25 t 100 people (+their goods and consumables) and 15t cargo or more cargo and less people. You engineering fellows, is that feasible with 3-4 refueling cargos?
My guess is the breakdown of the 5 kg is :0,7 kg of oxygen, turned into CO23 kg of water1,3 kg of food, So there would be no allocation for recycling at all?The oxygen can be recycled from CO2 using the sabatier process and some hydrogen, either stock of from the water coming from the food combustion. As long as the unit weighs less that ,7*100*180 = 14 tonnes, including solar cells to run it, then we're ahead on that.The water should be easy, the ISS already does that. We need to treat 300 kg per day, plus whatever is used for sanitation and cleaning. We can allow for some of it to get dirty, since even dirty water will be a good Martian import. Again 5x100x180 = 52 tonnes, and we should be able to have a good cleaning system for much less mass than that.The food will become compost. It'll be recycled on the colony.
Although overall water recovery rates are less than 100% for the assumed ECLSS system, there is a net surplus of water produced. This surplus occurs because additional water is added to the system in the form of water in the food that the crew consumes. Although the food is “dehydrated” it still contains approximately 28% water. The result is that, under the assumptions made for the study, no additional water needs to be added to satisfy water or oxygen generation requirements. Further closure of the ECLSS system will not reduce total logistics requirements.
Water reclamation from H2O contained within food promotes water-rich operating conditions for the partially closed ECLSS. As such, only 30 days of contingency water and oxygen were required to be delivered with the habitat, resulting in 362kg and 99kg of water and oxygen requiredrespectively
>On the other hand, long-run hygiene and laundry needs in excess of this report are something I've heard speculation about.
One snippet from the report states that water needs are filled mostly by food water content based on presentday space-food menus:
Soylent includes fiber.Remember, this is for 3 months, not for surface living.
People can pay more for more food, then. Problem solved. But for those willing to skimp, save $10,000-100,000 and go with Soylent on the way there, that option should be available to them.
Soylent tends to increase flatulence, from what I've read. We really don't want unpleasant conditions for all during the trip.
Quote from: llanitedave on 02/03/2016 02:35 amSoylent tends to increase flatulence, from what I've read. We really don't want unpleasant conditions for all during the trip.They can just open a window.
A) Where do you get 5kg/day?
B) Wait, what? 10 cargo missions per crew mission... of MCT?
And how many propellant missions per crew mission is that?
If you limited it to 6km/s each = 5:1 mass ratio @ 380s (probably not reasonable, given 3.2 C3, 0.5 minimum to MTO, more for single-synod reuse, and largely propulsive SSRP EDL), 40 prop launches to feed 10 cargo launches
"Why would anyone want to live on Mars?? I wouldn't want to! This is a fool's errand and should be stopped!""Why would anyone want to just drink Soylent?? I wouldn't want to! This is a fool's errand and should be stopped!"
If you're going to Mars for years, drinking a protein shake on the way is going to be the very least of your psychological worries, I PROMISE you. Ridiculous.