manned mission to Mars, favorite plans and architectures

[JonClarke]

I don't remember posting it <img src="/images/icons/smile.gif" /> but some was done by a coilleague in Portugal <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[qso1]

I posted some of the conceptual 3D stuff I did months ago but I'm not sure if thats what your referring to since your reply was to JonClarke. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[kelvinzero]

I saw that, pretty cool. Also I just watched "The Mars Underground" DVD from my video store. That was fairly convincing. I especially like the part about sending the automated part first and proving it out before sending people, so they definitely have a home with fuel and air so long as they manage to land.

 

[qso1]

I once favored the Von Braun approach and if we could get a budget for that, it would still be nearest the ideal way. But part of what sold me on a modified Zubrin approach was the idea of sending out habs unmanned. For one thing, a lot of unmanned research can be done and I pointed that out in the story.<br /><br />Imagine unmanned rovers not much larger than toasters that are deployed from the landing gear of a manned lander. These along with the larger lander can do lots of science on mars while waiting for humans to eventually occupy them. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[gunsandrockets]

<I posted some of the conceptual 3D stuff I did months ago but I'm not sure if thats what your referring to since your reply was to JonClarke. ><br /><br />The art JonClarke posted was a simple illustration of white outlines on a black background with captions describing the mission path. <br /><br />Sadly I don't recall the art you are refering to, I must have missed it.

 

[qso1]

I wasn't sure what JonClarke posted and do not recall seeing his. In Amazing Images, I have a couple of images in my 3D stuff thread which show Mars landers at the bottom of page 1. I also show a lunar base crew witnessing a lunar eclipse from the moon. An eclipse that is to take place in the summer of 2018, can't recall what date it was offhand. From Earth, it will be visible from the middle east.<br /><br />On page 4 you will see a shuttle derived launch vehicle on the pad and a training class with a model of an SDV that shows how the mars landers are packaged for flight.<br /><br />I use astronomy software to plot the locations of planets and stars for key scenes which is how the lunar eclipse from the moon was done. I have some other images posted in other threads but they were over a year ago and I have already forgotten where they are. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[JonClarke]

Here is an image by Antonio Maia of Portugal of the Mars Transfer Vehicle and Mars Habitat of the MARS-Oz reference mission docked together in Mars Orbit. The MTV ferries 4 crew to and from Mars orbit, the habitat sustains them on the Martian surface. Not shown is the cargo lander, which contains the rovers, ISRU land and the ascent stage. This is already on the surface and looks very similar to the habitat module except it is slightly longer.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[gunsandrockets]

Nice art. I hadn't seen that before. There is one little problem though, the dark portions of the craft are so dark they disappear right into the dark space background.

 

[qso1]

That makes for a realistic image except for the fact the dark areas would be slightly illuminated by mars down below.<br /><br />I render my graphic novel space images with only one light source which simulates the sun, except in cases where the vehicle is near a planetary body and its reflected light. The images are not as visually stimulating as say Babylon 5 images of ships where there are no nearby sources of light but always some background nebula or something lighting the ship with at least two sources of light. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[JonClarke]

I agree!<br /><br />My technical quibble with the art is that he should have had the hab docking point close to the centre of mass. My fault for not specifying this.<br /><br />The MDS is also somewhat simplified.<br /><br />Below is a view of the MTV (without dark background and hence the opposite problem) in the cruise to Mars configuration. Again I have some minor technical quibbles with the resentation, specifically the configuration of the payload doors (which only need to be present).<br /><br />But the art work is far better than anything I could do, so i won't complain!<br /><br />Jon<br /><br /> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[qso1]

The image I posted here is one that shows deployment of a propellant resupply vehicle using a shuttle "C" type vehicle. But one designed not to re-enter and burn up upon mission completion. Instead, the Payload Element (PE) as I call it, becomes the spacecraft upon reaching orbit.<br /><br />Not shown in the image is the propulsion bucket which is jettisoned at main engine cutoff. This then activates deployment of the solar arrays from the aft section which they are partially deployed in the image. A heat radiator is deployed as well. Docking with shuttles or other vehicles is accomplished via docking port at the fwd end. A nose cap protects the docking fixture until it has been jettisoned which in this image, has already occured.<br /><br />One of the advantages this concept had was that the fairing panels were hinged and provided protection from micrometeoroids when closed. They are shown open here. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[qso1]

I forgot to mention that as with all my concepts, this is meant only to reflect what may be possible from an engineering and scientific standpoint and is used primarily in my stories for the purpose of having an original variation to well worn ideas. That is, I didn't come up with how to get to mars...or the NASA reference mission spacecraft. I just design my own and say they are NASA designed craft in the stories. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[gunsandrockets]

http://uplink.space.com/showthreaded.php?Cat=&Board=businesstech&Number=710733&page=0&view=collapsed&sb=5&o=0&vc=1

 

[gunsandrockets]

<I’d like to see a real Interplanetary Transport Vehicle, or ITV.><br /><br />Propulsion? Electric, chemical or NTR?<br /><br />My own favorite architecture would also have a reusable ITV with spin artificial gravity. But to achieve reusability and a short trip time it has to employ a complicated dual-mode nuclear propulsion section plus aerocapture of the crew section into LEO. <br /><br />

 

[qso1]

When I first started writing space travel stories based on realities such as budgets and NASA back in 1973. I started with a mission to mars by first looking at the Von Braun concept which featured some measure of reusability. Then decided the same mother ship with different types of surface vehicles could be employed for Venus and Mercury. Over the years my writing and illustrating was on and off and I never considered my stuff publishable. But I guess my craft was as close to being a reusable ITV as I could get.<br /><br />But as time went on. I could see getting humans to mars was gonna get tougher to approve budget wise. I ran my ship through the budget process and found that the craft itself wasn't the problem so much as it having to have enough docking and propellant capacity for the surface vehicles. Even now, the design I featured in my current works would be able to fulfill the ITV role, requiring mainly thermal protection when utilized for Venus and Mercury. Im assuming your looking for a full blown ITV that can go to all the planets and thats the main difference between my variation of the ITV and your ITV.<br /><br />I originally wanted SSTOs for mars landers but recent times and the quest for an SSTO having failed has driven me to the more conventional two stage lander. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[gunsandrockets]

<No, I am proposing using LH2/LOX engines exclusively [for the Mars spaceship]. Water would simply be the easiest way to transport propellant. Once in Space Solar energy would be used to breakdown water as it is needed.><br /><br />The Problem of Chemical Propulsion<br /><br />Using chemical propulsion means a pretty enormous spacecraft. It takes a lot of chemical propellants to do the job due to the limited ISP of even the best hydrogen/oxygen rocket engines.<br /><br />The Problem of Water as a Storage Medium<br /><br />For the trip outbound from Earth, water can't be used. You can't instantly convert stored water into hydrogen and oxygen for burning in the rocket engines. The total time of the trans-mars-injection burn won't exceed an hour and will more likely be less than 15 minutes.<br /><br />For the Earth return trip stored water could be used, but that is more trouble than it is worth. Your spacecraft would need three sets of tanks: one set for water storage, one set for oxygen storage, and one set for hydrogen storage. Until reaching Mars, the hydrogen and oxygen tanks could remain empty, but before the return to Earth those tanks would have to be filled by converting the water in the water storage tanks.<br /><br />During the long process of converting the water to fill the hydrogen and oxygen tanks, that hydrogen and oxygen would still be subject to the problems of boiloff losses. To convert the water into hydrogen and oxygen would require an enormous solar array to crack the water in a reasonable amount of time. The hydrogen and oxygen tanks would still need heavy insulation to limit boiloff losses during the time they take to fill. But passive cooling might have to be supplemented by active cooling provided by even more electric power.<br /><br />All you do by using water for storage is trade off some boiloff time for the extra mass of the water storage tanks and the extra mass of the super-sized solar array. Instead of cracking water a smaller solar a

 

[gunsandrockets]

<Im assuming your looking for a full blown ITV that can go to all the planets and thats the main difference between my variation of the ITV and your ITV. ><br /><br />Nah. My concept spacecraft was originally just a Mars Transfer Vehicle, though it could be used for NEO, lunar and Venus missions too. In that sense it resembles bpfeifers ITV concept a little bit.<br /><br /><I started with a mission to mars by first looking at the Von Braun concept which featured some measure of reusability. /><br /><br />I like the Von Braun 1969 nuclear concept. The tragedy is that all the key elements were in place for that concept to travel to Mars before 1984, but the end of the moon race and the budget cuts which followed ended that dream. Too bad.

 

[qso1]

gunsandrockets:<br />The tragedy is that all the key elements were in place for that concept to travel to Mars before 1984, but the end of the moon race and the budget cuts which followed ended that dream. Too bad.<br /><br />Me:<br />The worst part was the cuts were built on a false cost argument. But thats a subject for another thread. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[scottb50]

Using chemical propulsion means a pretty enormous spacecraft. It takes a lot of chemical propellants to do the job due to the limited ISP of even the best hydrogen/oxygen rocket engines....<br /><br />As far as I know Hydrogen and Oxygen offer the highest ISP of any chemical fuel.<br /><br />For the trip outbound from Earth, water can't be used. You can't instantly convert stored water into hydrogen and oxygen for burning in the rocket engines. The total time of the trans-mars-injection burn won't exceed an hour and will more likely be less than 15 minutes...<br /><br />Once you set course for Mars you don't continue to fire your engines, you coast. During the transit there is more than enough time to break-down the water needed to slow into an orbit around Mars. If you use Solar energy both to breakdown water and cryogenically store what you need the stored propellants can be kept to a minimum.<br /><br />For the trip outbound from Earth, water can't be used...<br /><br /> As above you aren't thrusting all the way to Mars orbit. Where you would use water enroute is powering fuel cells to assure a constant and clean flow of electrical power. <br /><br />For the Earth return trip stored water could be used, but that is more trouble than it is worth. Your spacecraft would need three sets of tanks: one set for water storage, one set for oxygen storage, and one set for hydrogen storage. Until reaching Mars, the hydrogen and oxygen tanks could remain empty, but before the return to Earth those tanks would have to be filled by converting the water in the water storage tanks....<br /><br />Sort of true, except the water tanks could be big condoms and it could be ice until needed. Obviously you would need LOX and LH2 tanks, but they could be the same tank outbound and inbound, just refilled as the supply is used.<br /><br />During the long process of converting the water to fill the hydrogen and oxygen tanks, that hydrogen and oxygen would still be subject to the problems of boiloff losse <div class="Discussion_UserSignature"> </div>

 

[gunsandrockets]

<Where you would use water enroute is powering fuel cells to assure a constant and clean flow of electrical power.> -- one example of many instances.<br /><br />Alllrighty, then!<br /><br />Well folks, you can't say I didn't try.

 

[qso1]

Scottb50:<br />Using chemical propulsion means a pretty enormous spacecraft. It takes a lot of chemical propellants to do the job due to the limited ISP of even the best hydrogen/oxygen rocket engines....<br /><br />Me:<br />That would be true were it not for one thing. ISP for LH2/LOX propulsion is about 450. For nuclear thermal propulsion its about 900 or so. This implies the need for a chemically propelled vehicle to be around twice the size or mass of a NTR propelled vehicle. However, the NTR looses a good deal of advantage from the mass of the radiation protection shielding that the design is said to require for crew protection.<br /><br />Hydrogen and fluorine offer the highest ISP AFAIK but was never used because its not as stable a combination as hydrogen/oxygen. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[gunsandrockets]

There are more non-chemical rocket options than a high thrust NERVA type NTR. Solar Thermal Propulsion could have an ISP greater than 800 seconds. Then there is low pressure NTR which might have an ISP greater than 1200 seconds. And then there all all the electric propulsion systems with ISP's ranging from 1,200 seconds on up to 20,000 or more.

 

[kelvinzero]

Ive been brainwashing myself over this week with the 'Mars Underground' DVD, playing it in the background while I do other stuff.<br />It suggests a 6 month travel time, 18 month stay, 6 months back.<br />Im sure it is biased, presenting just one side, but what annoys me is the presented counterargument that we dont know how to safely live in space that long.<br /> It sometimes feels like all we have been doing for the last 35 years is just sending people up to sit in LEO for a bit, and we haven't even mastered the just sitting there bit.<br />I really think the technology of just putting people in a sealed container and sustaining life with just power should have been solved by now. You dont need to go into space to begin practicing it, or need a space agency to justify the need for it.<br /><br />So thats what I would like to see in a mars mission: No return plan. Instead you just keep sending missions with interchangable components, each capable of supporting life for its 4 crew for at least 5 years plus replacement parts for the previous missions.<br /><br />Just watch a politician trying to cut the budget to nasa then.

 

[gunsandrockets]

About your mission design...<br /><br />At first glance your plan looks very similar to the NASA DRM 1.0 except it's even more conservative, no nuclear power or nuclear propulsion. While your MTV reminds me of the MTV from the ESAS plan for Mars. Combining the MTV with Earth Return propulsion preserves certain abort options the DRM 1.0 lacks.<br /><br />I have two principle questions regarding your plan. The first is about crew size. Your payload masses appear very similar to those from the NASA DRM 1.0, but your mission is for only 4 crew while the NASA mission supports 6. The even smaller payloads of the NASA DRM 3.0 still supports a crew of 6. Are you being overly conservative with your estimates? Couldn't you easily accomodate a crew of 6? (Or alternatively cut your mass estimates by 1/3?)<br /><br />The other question I have is about the pressurized rover. For what seems like a very conservative plan, why is the pressurized rover included with the Cargo Vehicle instead of with the Habitat? Zubrin included a 1000 km range pressurized rover with his habitat because he understood the achilles heel of his Mars Surface Rendezvous plan is getting the crew from the Hab to the ERV. In the case of your plan it's getting the crew from the Hab to the MAV.<br /><br />Clearly your plan anticipates landing the Hab and Cargo Vehicle so closely together that part of the Cargo Vehicle can even be dragged over to link up with the Hab. But what if there is a problem landing that prevents a close touchdown? If the MAV ends up beyond foot range or beyond unpressurized-rover range from the Hab, your crew ends up stuck on Mars.<br /><br />

 

[qso1]

Correct, but since the question of chemical vs nuclear came up, I decided to compare the chemical ISP with the only nuclear systems to have had engine test firings which are the NTR concepts developed under the NERVA program. I selected a design for my story spacecraft based on VASMIR research which looked at the time I chose it, to be going somewhere.<br /><br />I'm not sure where the VASIMR program is going now. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>