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Rion, you keep focusing on your particular project. You will notice I did not repeat the Roadrunner project on every threat throughout this board. If you are interested in work on Roadrunner, please read the thread "Mars Society Initial Mars Mission" under the "Mars Society International" category. By the way, I feel Adrian should delete the MOLTOV thread under "Human missions"; you already have a thread by that name under "Unmanned probes". This thread is for discussion of this particular mission plan. I exercised the courtesy of not flaming your project, despite its obvious duplication of ours. If you wish to discuss merging projects please do so under the aforementioned thread.
Um, maybe I shouldn't have mentioned the communicator. It can be built using technology I know about today, but it does require a new microchip and one piece of new manufacturing equipment. Since it is a single microchip it can be applied as a new form of wireless telephone to replace cell phones. It would have the advantage of no cell towers so much less expensive to operate, and very inexpensive to install a new system. It would also permit wireless telephone carriers to operate worldwide, or wherever their marketing guys go. It could also be used for a cable TV box, without the cable or satellite; this would make cable and direct TV obsolete. Gangs of these chips could be used for a trunk line, so communication between telephone exchanges without wires, optical fibres, microwave towers, or satellites. It could make the concept of a communications satellite obsolete. Since it would be completely secure and produce no detectable signal, the military would love it. Let's just say "no yet patented".
Arrival of the interplanetary spacecraft would aerocapture into highly elliptical, high Mars orbit. Aerocapture would involve dipping into Mars atmosphere, so it would approach Mars from behind then pass across the "front" of Mars during aerocapture. Normally this would result in the periapsis being in "front" of Mars as it orbits about the Sun, and the apoapsis being "behind" Mars. The orbit would be in the same plane as Mars orbit about the Sun. However, the orbit could be controlled during aerocapture to loop around Mars so the periapsis is "behind" Mars and the apoapsis is "in front". One half Mars year later (343.5 Earth days) the "front" of Mars would have rotated 180? but the orbit would not, so the apoapsis would be "behind" Mars. Departing on this trajectory would leave the spacecraft with a slower solar orbit than Mars so it would fall inward toward the Sun, toward Earth. The exact orientation of the elliptical orbit could be controlled for optimal orientation at time of Trans-Earth Injection (TEI).
Notice this design uses a reusable interplanetary spacecraft. All food and supplies for the return trip would be included. That means supplies for return are waiting in orbit for the astronauts. The only things sent to the surface are those things which will be left on the surface (except the astronauts themselves). In addition to efficiency, this has the safety feature that in the event that a free return is required, the spacecraft can loop around Mars and return directly to Earth, and it will already have supplies for the return trip. The MAV would only carry the astronauts, samples, and enough fuel for TEI.
I am the one who went into as much detail as I can to say that the low level of radiation from a Pluto nuclear jet engine will decay within 2 hours. Furthermore, what radiation that does exist is of a type that does not penetrate through skin. Extremely intense beta radiation can cause skin cancer, but I doubt you would get that intensity unless you stood directly in the exhaust of an operational nuclear jet engine for an extended period of time. I tried to say the quantity of tritium would be negligible and easily ignored, but if you are saying none would be generated at all, then so much the better.
Yes, catastrophic failure of a NTR or nuclear jet engine would produce a mess. Yes, any catastrophic failure would produce a mess, including a jet airliner falling out of the sky. I wouldn't want a 747 falling onto my house. Now how do we convince local yokels to say away from the debris of a crash? A rocket crash would have jagged metal shards as well as rocket fuel. Commercial communication satellites use hydrazine derivatives, such as UDMH, in the upper stages. That is toxic and hypergolic. These dangerous chemicals just scream "stay away". You could argue that encapsulated spent reactor fuel pellets are just the same; dangerous debris that should be collected with protective clothing by experts who know how to handle them. In fact, if the fuel capsules are large enough they would be easy to locate, especially with a Geiger counter.
Now comes the practicality. Politics is a strange thing. People have to become gradually used to an idea after an extended period of propaganda. It would be more effective to start with NTR upper stages and nuclear electric propulsion. After the public has come to think of use of this technology as routine, then we can consider nuclear launch vehicles. After all, we now have to deal with government officials and administrators who think the earliest they can send the initial manned mission to Mars is 2030. Apollo went from J.F.K.'s speech to men on the Moon in 8 years. Today we have much more advanced technology, and are debating how much is left of a launch vehicle that could do the job 15 years ago. I don't think we need to introduce something as politically controversial as a nuclear launch vehicle for the first manned mission.
I did mention Janyce's idea. That is using a Pluto derived nuclear jet engine, but configuring it to operate as Nuclear Thermal Rocket to get up to speed where the ramjet can ignite, then functioning as an air breathing jet engine as long as practical, then transition back to NTR for the final push to space. Notice I said "practical", not "possible". She believes it costs 20% to get 80% performance out of any theoretical aerospace technology. That means it would be much more cost effective to develop a nuclear jet engine to operate to high supersonic speed, rather than trying to operate as a ramjet to extreme hypersonic speed in extremely thin atmosphere. However, I don't think it is necessary for the first manned mission.
By the way, I also know Chris Hirata.
I was also thinking the exhaust from a ground-launched Nuclear Thermal Rocket would be radioactive, and therefore would not be acceptable until you're in space. It is an interesting idea. If you used liquid hydrogen as the reaction mass, as most NTR designs do, but use hydrogen with all the deuterium removed, then there would be no tritium in the exhaust. In fact, a NTR with pure 1H as its reaction mass would not have any radiation in the exhaust. Hmm, something to think about.
The problem with a ground-launched NTR is what happens in the case of catastrophic failure? As I have mentioned in a previous post, I have seen a video of nuclear reactor workers loading uranium oxide powder into a steel tube to make fuel rods. They just wore white lab coats, a plastic hair cap, and the same plastic gloves you get with oven cleaner. They poked the powder into the tubes with their fingers. Uranium before it goes into the reactor really is that safe. The uranium in Nerva was encased in ceramic capsules so strong that it could fall all the way out of orbit and strike the ground without cracking. The rocket would smash to bits, and you would have uranium fuel capsules littered all over the debris field, but all of the uranium would still be sealed. After a reactor is turned on the nuclear waste is very radioactive. The same video from a nuclear power plant showed a robot removing fuel rods and taking them to a storage pool; you don't want to be in the same room as spent reactor rods. This means launching a NTR upper stage and activating it after it is safely in orbit is just as safe as any rocket launch. However, catastrophic failure of a NTR launch vehicle would be a radioactive mess. All the uranium capsules would remain intact, but after the reactor had been operating the level of radiation from each capsule would be high. Catastrophic failure before the reactor is operational would only require a pair of barbecue tongs and a plastic bag to pick them up. After operation the capsules would be a radiation hazard.
That is quite interesting. Janyce Wynter recently told me that the Pluto nuclear ramjet would not produce radioactive exhaust. Janyce is an aerospace engineer with Bombardier Aerospace, she designs and tests business jets. I tried to work out the radiation effects of a uranium nuclear reactor on air, and found it produces some beta emitters with half-lives measured in seconds, and tritium. Tritium is also a beta emitter but has a much longer half-life. However, not much tritium would be generated. This calculation is different from what Janyce told me, but the extremely short half-life of the majority of the beta emitters in nuclear jet engine exhaust means it will dissipate quickly. The short half-lives are 7.13 and 26.9 seconds. The one with a half-life of 26.9 seconds will decay 99.63% to a non-radioactive form in 2 hours. The one with a half-life of 7.13 seconds will decay 99.90% in that time. Beta radiation is non-infectious and lacks the energy to penetrate beneath the skin, so is that really a hazard?
Tritium has a half-life in years, but only 0.0115% of the hydrogen of moisture in the air is deuterium, and only that would be transmuted into tritium. Most of the neutron radiation will not be absorbed by deuterium in the air, so most of the tiny quantity of deuterium that is in air will flow through without becoming tritium. Is this really a hazard?
I met with my aerospace engineer friend over the Christmas holidays. She suggested the reusable interplanetary spacecraft be built from a self-launching hull rather than TransHAB. This would permit sending a very large enclosure with a rigid hull in a single launch. Of course, since self-launching technology is her idea, she is biased towards that. However, this would permit a very affordable yet reusable interplanetary spacecraft.
The other technologies are a high-efficiency life support system, and faster than light communication. A chloroplast based life support system. This recycles carbon dioxide and water into oxygen and carbohydrates. Operation would be entirely within the enclosed environment of the spacecraft, so no gas losses to space. Some carbohydrate could be fed to yeast to produce protein; the result would have the same carbohydrate and protein content as potatoes. Depending on the yeast variety selected, it could either be tasteless or quite flavourful. Some varieties of yeast are very rich in vitamin B complex. The Johnson Space Center's Advanced Life Support project claims to have achieved 97% water recycling efficiency, including water from all sources. Dehydrated food can still be up to 50% water, so a high efficiency system means transporting only dehydrated and dry food. Producing a potato substitute reduces the mass of dehydrated food necessary. Oxygen production would produce so much carbohydrate that it would only be consumed if the astronauts ate nothing but that. Consuming stored food (for balanced nutrition) means production of excess carbohydrate. That would be incinerated to extract all possible water. The result would be 100% oxygen recycling and 97% water recycling, with water loss replenished from residual water within dehydrated food. This greatly reduces the consumables necessary for the mission.
The communications idea is a quantum communicator. I have an idea how to create one, but it requires developing a new microchip. That's expensive. The quantum communicator means instantaneous communication between Earth and Mars. So that means real-time telephone conversations, television, and internet access. It also means a remote surgical suite can permit a doctor on Earth to operate on astronauts on Mars. That permits reducing the crew to just 4.
A spacesuit for Mars would also use a reusable sorbent for carbon dioxide extraction, rather than lithium hydroxide. Reusable sorbents are silver oxide, or solid amines. These mass more than lithium hydroxide, but can be reused by heating. Lithium ion batteries have been developed that can withstand -40?C temperature. Mars can get colder than that, but the inside of the suit must be comfortably warm. Current batteries for the EMU (the current space shuttle spacesuit) can only withstand 30 charge/discharge cycles before they are reduced to 60% capacity. These lithium ion batteries can withstand 1500 cycles before they are reduced to 80% capacity. That means the batteries can endure the entire mission. Eliminating consumable sorbent cartridges and batteries means the only consumable for EVA is gas lost through suit leaks or lost the airlock during depressurization. Eliminating suit consumables also reduces launch mass.
Ok, can we get away from hyperbole and insults? We are all very passionate about Mars and want to get there within our lifetime. I personally would like to own the company that builds the first colonization ship to Mars. Not the first manned mission to Mars, the first ship to carry colonists for permanent emigration to Mars. I want to see it fly within my lifetime. That means the first exploratory manned mission to Mars must be very soon; we can't wait until 2025.
Rob C Willis and Mark S, you are among the most technically capable individuals I have communicated with on this board. I have communicated with Mr. Willis on the previous message board about the Energia launch vehicle. It is truly refreshing and encouraging to be able to hold meaningful conversations. Let us not start tearing each other down. A humans to Mars program will always require participation by multiple countries. The International Space Station could not have been built without Russian participation: NASA did not have any form of recycling life support system, or a docking mechanism that could handle two craft each of which mass 100 tonnes, such as the space shuttle orbiter and space station. NASA also lacked the means to automatically dock modules in orbit. Russia had these, and still does. Since Apollo has been well and thoroughly eliminated, NASA did not have a capsule or any form of lifeboat for the station; Russia had Soyuz as well as a relatively inexpensive cargo re-supply vessel. Canada contributed the remote manipulator system (CanadArm) for space shuttle, and the space station remote manipulator system (CanadArm2) for ISS. If nothing else, participation by multiple countries is necessary to pay for a mission to Mars. You could argue that Russia didn't contribute money, but they did contribute the necessary technology I already mentioned.
If the Russian news reports that they will abandon Baikonur by 2005 are just bull shit attempts to pressure Kazakhstan to reduce their "rent", then we still have the Energia launch facilities. I have heard various reports of the poor condition of Russian facilities, but the strongest and most detailed criticism is from a major American aerospace company, and large American companies are notorious for slandering their competition. Russia has always built their aircraft, military bases and space facilities so they are robust and can operate after severe weathering has caused major cosmetic damage. Up-to-date, operational Russian air force airfields look to American eyes as if they have been abandoned for decades. The guy I am referring to said that building #112 had major rust on its support walls when I talked to him 1 month before the roof collapsed. Pictures I have from a tour group that went through in April 1997 shows MIK-RN sparkling clean and no rust. The rail tracks leading from MIK-RN to the launch pad have tall weeds growing through them, but the ties are concrete and the rails look like they are in good shape; all they need is someone to mow the weeds. I can't tell the condition of the gantry from the pictures, but it is there. One Buran orbiter was located outside in a safing area, and had a significant number of heat tiles hacked off its nose. This was not the Buran orbiter that flew in space once, but I can't tell if it is one of the other 2 orbiters or one of the full size mock-ups. It does have real tiles, not just a paint job.
I encourage both of you to continue working on new launch vehicle designs. I will still advocate a simple, minimum-change design for the first mission. This could be done with Energia LV using 4 strap-on boosters and EUS to lift large modules into LEO for assembly, or by breaking the mission into independent craft slightly smaller than Mars Direct and using Energia for direct throw to Mars. Then we wouldn't have to develop any Trans-Mars Injection stage, the EUS would be the TMI stage. Shuttle-C doesn't have such a side-mounted stage available, at least not such a large one that could be used for direct throw, but it could lift large modules to LEO. Notice the variation of Shuttle-C that I advocated: the same vehicle assembly and launch facilities as the space shuttle, no change. The same external tank and SRBs, no change. The same total launch mass, thrust profile, and total mass delivered to orbit, no change. The same external diameter as the shuttle orbiter's fuselage to avoid aerodynamic problems or reduced lift from increase drag. The same 3 main engines, same fuel pumps, same Orbital Manoeuvring System (OMS). Replacement of the orbiter by an engine pod with ablative heat shield, X-38 derived parafoil, orbiter launch software and X-38 landing software, and a Titan IV derived fairing means a very low cost, relatively small piece of hardware. The only new launch equipment would be a support pillar to replace the orbiter wing supports on the Mobile Launch Platform (MLP). The only new landing equipment would be a medium flat-bed truck with dual rear axle and a truck crane. The only new equipment onboard such a Shuttle-C engine pod would be a radiation hardened, single board computer, and smaller manoeuvring thrusters; both are available off-the-shelf. This is different than the variation of Shuttle-C depicted in Astronautix; that one uses just 2 SSMEs, is expendable and has lower lift capacity.
Don't worry about the "establishment" not accepting anything non-American. One document I have on Magnum lists several variations, I just keep talking about the variation that is closest to the "baseline" established before the study. Variations include:
- 2 SRB's, ET core with 5 foot stretch, 2 "low pressure" SSME's, kick stage
- 4 SRB's, ET core with 5 foot stretch, 3 "low pressure" SSME's, kick stage
- 2 SRB's, ET core with 5 foot stretch, 2 pressure assist modules with 2 SSME's per module, kick stage
- 2 pump-fed Liquid Rocket Boosters with 3 RD180 per LRB, ET core with 5 foot stretch, 2 "low pressure" SSME's with LOX/RP fuel, kick stage
- 2 pressure fed LRB's with 4 "800K" engines per LRB, ET core with 5 foot stretch, 2 "low pressure" SSME's with LOX/RP fuel, kick stage
- 2 Liquid Flyback Boosters with RD180 type engines, ET core with 5 foot stretch, 2 "low pressure" SSME's with LOX/RP fuel, kick stage
Each of these variations has different development cost, operational cost, and lift capacity. However, notice the use of RD180 engines. Another page of the same document lists the engine options: RS-68, SSME w/PA mod, TRW Eng., RD-170, RD-171, RD-180. Notice the inclusion of Russian engines in design of Magnum, which is a Shuttle derived vehicle.
You do make a very good point regarding Energia performance. The Buran with maximum payload (30t) would have a total mass of 105t. The engine section included the RCS, but that functions as the equivalent of the American shuttle's OMS. This does raise the question of how the Buran would get into a 200km circularized orbit. It is interesting that the thrusters onboard Polyus were the RCS; I didn't know that.
There is a NASA web page I am referencing that lists Family Energia, Model EUS, as capable of lifting 88,000kg to LEO. It doesn't specify what altitude they mean by LEO. That page is where I get my figures for directly throw to escape velocity; it includes C3=0, 10, 50, and 100. I interpolated for C3=15 and 25. The page also includes a row in the table for Family Energia, Model EUS/RCS, with the only column filled in for C3=100. I interpret that as a combination of EUS and RCS is possible, but it is only useful for outer solar system trajectories. I would post the URL, but I don't want NASA to take that web page down; it's too valuable to me. After I did post the URL for the X-38 reference page, NASA did remove that page.
The newsru.com articles I referenced are where I got the story of Baikonur being decommissioned. It does state so quite plainly in those two articles. I use www.translate.ru and www.altavista.com to translate from Russian into English. It's useful to use two different translation engines, and I believe that one from America and one from Russia should give a good, net translation. If this was just a story to scare the locals into reducing their "rent", then I am relieved. However, the articles did claim that reporters will be allowed on Plesetsk, and Lock-Mart is paying for the Angara launch site in return for profits from Angara launches. That would seem a rather bold claim if it is just bull shit.
Notice the throw mass for Energia I calculated in a previous message is just a hair under the capacity of Ares. I suspect it is 4 Zenit strap-ons plus EUS. This is one reason I suggested a TransHAB based inflatable Hab. Launch it deflated so it can fit within the fairing of EUS, then inflate once on your way to Mars. If you can reduce the mass just a bit, you can send the Hab with 4 astronauts with a direct throw from just one Energia launch. That is, if someone would repair the high bays of building #112.
This is quite a vigorous argument. Let me throw in my 2 cents worth.
The US military experimented with VTOL aircraft before the British developed the Harrier. I saw a documentary on an aircraft that flew horizontally, but landed on its tail. Only one pilot was ever able to land it without crashing. The Harrier solved the "land on your tail" problem, but it still takes quite a bit of fuel. The marines use them for air support from forward bases that don't have an airfield. One of the problems with a Harrier is fuel required to land; if a bullet hole drains too much fuel before you get base, you can't land without an airstrip. If there is an airstrip handy, then why bother with VTOL at all? Combat aircraft have to plan for battle damage.
VTOL launch vehicles traditionally don't have wings at all. That raises the problem of what to do if you don't have enough fuel left to land. A horizontal landing aircraft can glide, but a vertical landing craft cannot. Insufficient fuel = crash. If you do have enough fuel, then you are landing with a large quantity of rocket fuel. Rocket fuel must have a high energy density, so that makes it highly flammable if not explosive. Vertical landing is a risky business. It's safer to either use horizontal landing, or a parachute, or combine them in a parafoil.
The X-38 had a compact lifting body design, a parafoil instead of wings, and landing skids that did not require maintaining tire pressure in the vacuum and cold of space. You could argue that skids are not practical for a larger craft like the space shuttle, but fine for a small crew transfer vehicle.
I think Marks S is right that we should look where a rocket is the best vehicle. In fact, an expendable launch vehicle may be best for cargo that never comes back to Earth. That means simply sticking to a rocket like we have now and tweak its performance for delivery of satellites and space station modules. Use a small, reusable HTOL spaceplane as a crew taxi.
In fact, my engineer friend likes to advocate here paper for "self-launching". That is, a rocket that is specifically designed to launch nothing but itself, and the tank becomes a space station module. This permits a customer tank design that has structural integrity for long duration station modules, thermal insulation that won't flake off after a couple days, etc.
Self-launching station modules, expendable rockets to deliver satellites and station equipment, and a reusable SSTO crew taxi would provide the specialization required for a cost effective vehicle fleet.
MIK 112 is not needed to support Energia M operations from Baikonur, as much newer facilities built to support Energia-Buran are available.
Which building are you referring to? Several of the buildings at Baikonur are called "Building of Assembly and Test", in Russian "MIK". The Energia-Buran launch stack was assembled in MIK-RN, also known as building #112. That was the old vehicle assembly building for the N1 rocket. The new building for Buran was MIK-OK, building #256, but it is just the orbiter processing building. MZK, building #113, was a new building for loading propellants into the orbiter and payload, and for vertical static tests of the entire stack. The 2 high bays of building #112 had the roof collapse. The 3 low bays are still 52 metres high, and were repaired after the collapse to support ISS module staging. Are you suggesting the low bays, or building #256?
This will allow the RKA to cease Progress re-supply missions to the ISS, which have been maintained at the rate of at least two or three flights per year over the past five years. A Progress spacecraft costs more than an RD-170.
Do you really believe that RKA wants to cease operations? Re-supply is a very crucial part of ISS operations, it helps justify the existence of the Russian space agency. I suspect that RKA would not want to cease Soyuz/Progress operations any more than NASA would want to cease Shuttle operations. Those operations are quite spectacular.
Do you have cost figures for Progress and Soyuz spacecraft? The only cost figures I have are for launch vehicles. I would appreciate those numbers.
Rob C Willis,
I don't think you understand why I am paranoid about further advocating Energia. One month after I told a sales person at a major American aerospace company just how easily Energia could be reactivated, the roof collapsed. I am saying this is not an accident. Although the Russian investigation ruled out terrorism, I do not rule out industrial sabotage. I fear that further advocating Energia may simply result in more sabotage.
As for retiring Baikonur, two news articles from the Russian news service newsru.com state that Baikonur will be abandoned. The article from March 3, 2002 states "the Government of Russia has planned to allocate about 5 billion roubles (167 million dollars). So much Russia pays to Kazakhstan for one and a half year of rent of Baikonur." The article on January 18, 2002 states "to say goodbye to Baikonur, in Plesetsk it is necessary to finish construction of a so-called launcher number 1." That article also states the Russian Ministry of Defense didn't have enough money to complete the facilities at Plesetsk, so Lockheed Martin is paying for it in exchange for profits from Angara. The article says Angara is capable to win half the world market of space services. It also states that the opinion of Lockheed experts was Plesetsk was 70-80% ready for heavy Angara. If there is something inaccurate in these articles, please tell me; especially considering these articles are from a Russian news service, in the Russian language.
Yes, my figures for Energia LV with EUS do come from www.astronautix.com, and it states the Energia with 4 Zenits could lift 88 tonnes to 200km altitude without circularization, or the same mass to the same orbit with circularization if you add the EUS upper stage. The Polyus was supposed to use onboard thrusters to circularize. The Groza was the variation with only 2 Zenits and no EUS, it was supposed to lift 50 tonnes to 200km orbit circularized. However, my figures for Vulkan (170t to 200km circularized orbit, 8 Zenits) come from direct correspondence with Aleksandr Derechin, Head of International Division, RSC Energia. The last link is to my translation of his letter, it was in Russian. For more details see my Russian rockets page.
I don't mean to squash your work, Rob. New launch vehicle designs and new mission architectures are always a good idea. Together we will develop something that can be done; safely, effectively, and at a price that can be paid. If my comments appear to be criticism, realize the test of any serious proposal is its ability to survive critique. Your messages have already brought to light information I didn't know. Keep up the good work.
I think the problem with nuclear jet engines is that their exhaust is radioactive, just as the exhaust of NTRs.
Actually, the exhaust from a nuclear jet engine would not be radioactive. Neutron absoption requires a moderator, and I explained in another message that neutron absoption of 99.795% of oxygen would just transmute it into another naturally occuring, non-radioactive isotope. Neutron absorption of the 0.205% which is 18O would just turn into 19O, which would decay with a half-life of 26.9 seconds into 19F, which is the natural, non-radioactive form of fluorine. The decay releases beta radiation, which is an electron. You would get more beta radiation from sitting in front of your computer monitor reading this message. 99.9885% of hydrogen is 1H, normal hydrogen, which would turn into deuterium with neutron absorption. 2H is the other 0.0115%, and it is natural and non-radioactive. Neutron abosption by deuterium becomes tritium (3H), which has a half-life of 12.32 years to become 3He by beta decay. The incredibly tiny quantity of deuterium in moisture in the air would not produce significant quantities of tritium. 3He is a natural occuring isotope of helium, although only 0.000137% on Earth. With nitrogen gas, 99.632% is 14N which would transmute into 15N, the other naturally occuring isotope. 15N would transmute into 16N, which beta decays with a half-life of 7.13 seconds into 16O, the predominant natural isotope of oxygen.
Fission of 235U involves absorbing a moderated (slowed) neutron to become 236U. That breaks down in a fraction of a second into Krypton 89Kr, Barium 144Ba, and 3 high-speed neutrons. These byproducts are highly radioactive, but primarilly release beta readiation. Krypton 89Kr has a half-life of 3.15 minutes to become Rubidium 89Ru. 89Ru half-life is 15.15 minutes to become Strontium 89Sr. 89Sr half-life is 50.53 days to become yttrium 89Y, which is stable. The other product of uranium fission was barium 144Ba. 144Ba half-life is 11.5 seconds to become lanthanum 144La. 144La half-life is 40.8 seconds to become cerium 144Ce. 144Ce half-life is 284.893 days to become praseodymium 144Pr. 144Pr half-life is 17.28 minutes to become neodymium 144Nd. 144Nd half-life is 2.29 quadrillion years (10^15 years) to become cerium 140Ce, which is stable. All of these decay steps emit a beta particle (electron), except the last one. 144Nd emits an alpha particle (helium nucleus) to become 140Ce. The extremely long half-life means extremely low rate of radiation.
This means as long as you ensure the nuclear fuel and its byproducts are contained, the exhaust will not be radioactive. Just stay away from the engines themselves.
My aerospace engineer friend who designs business jets told me of a nuclear jet engine that was built and tested about the time that Nerva was developed. It operates as a RAM jet and uses heat from a nuclear reactor as the propulsion energy. She suggested a horizontal take-off, horizontal-landing (HTHL), single stage to orbit (SSTO) spacecraft. It would use the engine as a nuclear thermal rocket (NTR) to accelerate up to speed where the RAM jet could work, then transition to RAM jet operation, accelerate to hypersonic speed and high altitude, then transition back to a NTR for the push into orbit.
She also suggested this technology could be used for commercial passenger jets. The airliner would attach the engines to the wing tips. Upon landing the craft would go to an area where the nuclear reactor engines would be removed and stored in a pit. Then ground equipment would tow the aircraft to the terminal where passengers disembark. After the passengers for the next trip embark (get on), it would be towed back out to the pit where the engines would be put back on. It would then taxi out to the runway for takeoff. This means passenger liners that operate with just enough fuel to accelerate to RAM jet speed, and then cruise on air and nuclear fuel. With almost no jet fuel, how would that affect airline ticket prices?
Commercial application of nuclear jet engine technology would rapidly develop this to a mature technology. Once developed it could easily be used for an "Orient Express" airline that uses a suborbital hop. Aerospace engineers have long stated that an aircraft that leaves the atmosphere entirely for a suborbital hop is easier to build than hypersonic cruise. Once airlines perform a suborbital hop through space, it would be trivial to accelerate to orbit and dock with a space hotel.
The alternative to a nuclear jet / NTR powered launch vehicle is Rocket Based Combined Cycle (RBCC) engine. As I just mentioned, that is the more difficult route. I would like to see the X-43 fly, it is necessary to continue work on this technology, but it is the high-risk high-payoff route.
Yes, I am talking about developing actual software to be used on an actual probe. The game is just a test bed, and a means to mass market it. We might want to sell it, or make it freely available to Mars Society members. This would permit average members like you and me to design Mars missions and test them with a simulation accurate enough to fly a real mission.
QNX is a high-reliability operating system. It does not use virtual memory at all because it is intended for embedded applications that must respond quickly to hardware interrupts; it cannot wait for a process to be swapped in, or a subroutine to be paged in. A real probe to Mars demands a high reliability system such as QNX or VxWorks. Both of these have been demonstrated in space: VxWorks was used on Mars Pathfinder, QNX on CanadArm2. I know QNX, not VxWorks. Sorry for the bias for something I know.
I just got notification from NASA that the Announcement of Opportunity (AO) for the next missions in the Small Explorer (SMEX) program has been postponed. Depending on the availability of appropriated funds, the SMEX AO should be released shortly after NASA's FY03 budget is signed. I swear someone at NASA is reading this board; the UNEX class mission I mentioned is part of the SMEX program.
I hadn't really intended to submit a bid this year, but start small and build up. That is, after I attended the 4th Canadian Space Exploration Workshop (CSEW4), it appears I will get the contract to produce regolith simulant for the Mars rover test facility, called Mars Dome, which the Canadian Space Agency is building. I have papers directly from the principle investigators of the APXS instrument on Sojourner, and the spreadsheet from the geologist who did the CIPW analysis for NASA. A geology professor at the University of Winnipeg is willing to work with me on it. I also intend to work with the University of Guelph to build an inflatable greenhouse for Devon Island. They want to build one, and I want to build one that can be made available for sale to grade schools, so a partnership is obvious. I also submitted an abstract for a paper on an advanced life support system for the Humans in Space symposium at Banff (a resort in Canada) this spring. I'm waiting to see if they let me submit the paper; the abstract is being pier reviewed. I intended to rally the Mars Society to seriously build a small explorer, but after I got some interest and proved my company by building something.
I did establish an email group for collaboration of those involved with the Roadrunner project. That group still exists, but hasn't done anything in about a year. I made it exclusive to those doing serious work. Although you don't have to have a Ph.D. to be part of it, you do have to be willing to put in serious work.
When we started to talk about this on the previous message board, there was some debate about what the mission would be. We held a vote: 2 people voted for a fly-by, 1 person wanted an impact penetrator, everyone else voted for a balloon. Chris Hirata told me that when he originally raised the issue of a fly-by with Maggie Zubrin, she didn't like the idea. She thought a fly-by was "been there, done that." However, when I mentioned this to Maggie, she didn't remember the conversation. Although a balloon to Mars would be new, the majority of MS members voted for a balloon so democracy dictates we do that anyway. After we started work, we discovered two other Mars Society groups that wanted to send a balloon to Mars. Chris Vancil's Mars Balloon group is working primarily on high altitude balloons here on Earth to prepare for Mars. The Spain chapter has chosen a balloon as their chapter project. They want to build the balloon itself, and they're raising funds. The Organization of Space for Everyone (OEPT) in Spain is recruiting members from all Spanish speaking countries who want to work on propulsion. All these groups have chosen to work together to send a Mars Society mission to Mars. The German chapter, however, was the last to jump on the Mars balloon "bandwagon" and they decided to do it alone, they don't want to cooperate with any of these other groups. They are trying to hitch a ride on the European probe called Mars Express. We'll see if they can do it.
We did have several qualified people on the project. For example, I have over 21 years experience in software development including real time software for embedded systems, including flight systems; and I have been a project leader/manager starting with the second year of that experience. The team includes an aerospace structural engineer who works for NASA, and was part of the Shuttle upgrade and X33. It includes another structural aerospace engineer who works on business jets, tooling, and aircraft testing. We had an electrical engineer from Cisco. I got the University of Manitoba to work on the propellant feed system (the professor said my simplification of NASA's design was so obvious that a single aerospace engineering grad student could complete it, with his supervision). One individual with a Ph.D. in plasma physics whose thesis was on magnetic containment for a fusion reactor is very willing to work on optimization of the ion engine optics. (He wants a paying job in his field. He's currently working for an oil company.) One MS member is completing his Ph.D. in aerospace engineering specializing in heat shields and aeroshells. He said he is willing to design the Mars entry vehicle. I have a letter from the president of the company that machined the parts for the joints of CanadArm2 stating he was willing to machine parts for me. I received some documents on the NSTAR ion engine directly one of the lead engineers at the Glenn Research Center who developed NSTAR. A local member is an electronics test technician, and routinely tests equipment in a vacuum chamber. I located suppliers of space photovoltaic arrays, manoeuvring thrusters, composite propellant tanks, and radiation hardened single board computers. I volunteered to be the chair of the propulsion group of the Mars Society's Technical Task Force. The communications group of the TTF is not working specifically on this project, but they are working on spacecraft-to-ground communications focusing on phased-arrays. The Deep Space Exploration Society wants us to use their 18-metre dish to receive telemetry because use of their facility by an organization like the Mars Society justifies their existence, they only ask us to pay for any new equipment required. An astronomer in Latvia had asked the Mars Society to pay for upgrades for a 32-metre dish left-over from the Soviet days in exchange for receiving telemetry from a Mars Society mission. I tried to contact him, but he hasn't responded. The former president of the Mars Society Canada had contacted him, so if we seriously pursue this we could contact him again. The communications group of the TTF also has contact with him. Having 2 dishes on different continents would give the Mars Society a small deep space network of our own.
If we choose to re-activate the project, members must realize it will take a great deal of time by a great number of members. There is a lot of work involved with developing a real probe to Mars. One argument I keep hearing from businessmen is that simply preparing a bid is expensive. However, it is only expensive because it takes a great deal of time by significant number of highly qualified individuals. Paying their salary is the expense. If Mars Society members are willing to donate their time to work on preparing the bid, then it won't cost anything. Just preparing the bid is a research project of its own; it requires designing the hardware and the mission to the point where it is practically complete.
Those interested in political support can write their congressmen to support NASA and its Small Explorer program. A paper letter carries a lot more weight than an email or a signature on a petition.
I just got notification from NASA that the Announcement of Opportunity (AO) for the next missions in the Small Explorer (SMEX) program has been postponed. Depending on the availability of appropriated funds, the SMEX AO should be released shortly after NASA's FY03 budget is signed. I swear someone at NASA is reading this board; the UNEX class mission I mentioned is part of the SMEX program.
Those seriously interested in infiltration could join the Republican or Democratic party (preferably we would have members in each) and start lobbying to support the NASA budget from within the parties. Those who don't want to that much work can write the congressmen to support NASA. A paper letter carries a lot more weight than an email or a signature on a petition.
Ok, I've been named. Well, I did volunteer at the steering committee meeting to be the volunteer coordinator. The technology roadmap team has been quiet for the last few months, and I haven't received any request for volunteers for projects yet. However, I do have a few projects I could use help with.
One idea is a Mars simulation game. There are a couple games out there right now, but what I have in mind is a lot more accurate and less graphic. There would be 2 parts to it. First you could enter the specifications of your Mars spacecraft and fly it to Mars. It would have some detailed calculations to allow you to engineer a spacecraft based on tank mass, engine mass, specific impulse (fuel efficiency), payload mass, etc. Formulas would check the design. The second part would fly a simulated mission with your spacecraft. The graphics are not that important, it doesn't require fancy 3D with texture maps, just an icon moving along a trajectory about the sun to its destination. However, the simulation software could be ultra-realistic. The spacecraft navigation can be real, and the "game" a simulation test bed.
There are a lot of parts to something like this. The GUI user interface would be written in Visual C++ or Visual Basic. The navigation software, however, would have to be strictly C language. The navigation software would have to run on the operating system QNX, but the simulation would run on a PC. That gets into portable code.
Now this gets interesting because one component of the navigation is astronomical image recognition. A comparison of the image of known asteroids to the star background can triangulate the spacecraft's current position. That requires taking a digital image and recognising key stars and known asteroids. I accumulated a few code samples, but image recognition is not one of my specialties. I am a programmer myself.
We could get extreme and start entering gravitational perturbations from an increasing number of planets and asteroids, and even enter the orbits of known asteroids to avoid collision. We could also include the math of unusual orbital manoeuvres such as continuous thrust all the way to Mars, or slowing raising the orbit of a spacecraft with an ion engine.
It could be quite interesting. Any takers?
the Mars Society needs to really do something functional with regards to space, and Mars itself ... Sending a probe to Mars
This is a very big issue. We had discussed exactly this point on the previous message board, and that is where the Roadrunner project came from. I had contacted the director of the Small Shuttle Payloads Project about deploying a very small probe as a Get-Away-Special. The price was $8,000 for a US educational institution or $27,000 for anyone else, but only if you bring the payload back down with the Shuttle. If you deploy the same payload, the cost is $2 million. He also mentioned that if we could get a NASA agency to sponsor us we could get a free ride on the shuttle. We assembled a team, and started work on the ion engine for it. When Mars Scout 2002 came out I attempted to prepare a bid. As a Mars Scout, NASA would pay up to $325 million, but it would have to be launched on an expendable launcher. I got a price quote from Orbital Sciences for a Pegasus rocket: $25 million for direct injection into trans-Mars trajectory, but the kick stage would produce 25Gs of acceleration. For a total mission cost of $32.5 million, that would be 10% of the maximum NASA set and would leave us $7.5 million for construction and operation of the probe. We also arranged for an 18 metre dish ground receiving station at the cost of reception electronics. I could mention the highly qualified individuals on the team and organizations involved, but when I asked Robert Zubrin for permission to submit it as a Mars Society mission, he said no. He thought a multi-million dollar mission like that was too much. I don't want to sound like I'm criticizing our illustrious founder, but if you want to talk about sending something to Mars you will have to convince Dr. Zubrin to think big. That is what I sent to my contact on the steering committee last spring. (Hmm. I'm thinking bigger than Dr. Zubrin. Scary) To address this issue again we should return to the minimalist design and budget to fit well below the $15 million budget of a University Explorer (UNEX) class mission.
Adrian has pointed out the problem with CafePress. They put so many links and advertisements to themselves that customers tend to just setup a "store" for themselves and avoid purchasing anything from anyone but themselves and CafePress. I did find a Canadian producer for t-shirts and created a web store myself so local customers can avoid cross-boarder taxes. The products I mentioned are, in fact, CafePress. I only added $1 per product as profit margin to support the local chapter, but still haven't sold a single item through CafePress. I was hoping the license plate frame for Cindy would be my first sale, but since Adrian has let the cat out of the bag, I expect no one will sell anything.
Winnipeg Store
Pardon me if I get out right paranoid about the Energia launch vehicle. I tried to advocate the Energia. I contacted the director of the international division of RSC Energia to ask if it is available. He said it is. At that time the only thing necessary was rebuilding a manufacturing facility for the core module, but using existing RD-0120 engines. I even got a NASA employee at Michoud excited, and he said he would see if he could leverage the fact that he works where the external tank for the American space shuttle is built to get the Energia equivalent restored. However, one month after I mentioned to an employee of Orbital Sciences just how easy it would be to restore Energia, the roof of MIK 112 collapsed.
We do, in fact, have to realize there is a world outside the US. The Russian government is not at all impressed that Baikonur is now outside their country. RSC Energia would very much like to get the Russian government contract to build Energia-M, but they lost to a competing Russian company that produces Angara. One reason is that Angara has launch facilities at Plesetsk, inside Russia. The cost to upgrade Plesetsk to accommodate Soyuz and Angara launches is less than 2 years rent to Kazakhstan for Baikonur. Economics and Russian politics dictate abandoning Baikonur, and that means Energia-M will never be. Energia LV with the EUS (Energia Upper Stage) can lift 88 tonnes to 200km circular orbit, but can throw roughly 29.38t directly to TMI (Trans-Mars Insertion) with C3=15 km/s^2 which is an 8 month trip to Mars, or 25.97t to C3=25 which is a 6 month trip to Mars. Vulkan LV with 8 Zenit strap-on boosters could lift 170t to 200km circularized orbit, so it should be able to throw roughly 56.75t to C3=15, or 50t to C3=25. That would be a massive rocket, even greater lift than Saturn V. Since the upper stage of Vulkan would have a single RD-0120 engine and diameter the same as the core stage, that would give it a 7.8 metre fairing. The habitat for Mars Direct was originally designed for 8 metre diameter, and a single floor plus storage for pressurized rover and surface science equipment; it was calculated to mass 28.42 tonnes including artificial gravity tether and the astronauts. The Vulkan would be much larger than necessary. Again, RSC Energia would love to build it, but I think it falls into the category of "would be nice if".
Shuttle-C with only 2 SSMEs and configured to be disposable would lift only 77t to 400km circularized orbit at 28?. The configuration I described with 3 SSMEs and a recoverable engine pod could lift 91.9t to 407km orbit at 51.6? (ISS). Magnum with 2 SRBs, 4 SSMEs and a kick stage for circularization would lift 79.8t to 407km orbit at 28?, and fairing with 7.62 metre interior diameter, 8.4 metre exterior. True, the Shuttle has 4.5 metre interior diameter cargo bay, but the exterior is 5.2 metres. If you use a 4 Zenit Energia with the side-mount EUS, it has a 5.7 metre exterior. The hull of a solid habitat can withstand the hypersonic air flow during launch, so no fairing is required. That means the exterior diameter counts. I don't see a big difference between Shuttle-C and Energia. The primary concern is who we can convince to build it.
I am very pleased to hear the Kosberg factory remains intact. Restoration of manufacture of new RD-0120 engines provides a lot of options.
I wish the MS would generate for sale bumperstickers, keychains, baseball-type hats, etc., for purchase with its logo (which needs updating), a slogan, and its web site address on those items.
Wish granted.
At the Mars Society Mall you can get Mars Gifts such as Hugg-A-Planet soft globe, a few Mars games, or the Red-Blue-Green flag. The "Mars Ball" that is advertised as (clearance) has been sold out for months. Mars Society T-Shirts and key chains can be purchased here. The link for hats is "temporarily" broken. At the last convention, Maggie was selling round mouse pads with the slogan "We must go for the knowledge, we must go for the future" and the web site address. I won one of those pads as a door prise. You can get it at the Mars Society Bookstore, but the ordering procedure hasn't been determined yet. That web site also has lots of books, the Stanford Convention shopping bag, the Ares CD and "Mars VR" CD, and a "Mars Direct" video.
Some local chapters also sell items. I could link you to my chapter's store, but I don't want to compete with the main Mars Society web store. I have available an ash-grey t-shirt with the MS logo on the left breast, as well as a sweat shirt, golf shirt, and women's T-Shirt with a provocative slogan. (I came up with the women's T-Shirt design myself.) I also designed a mouse pad, but Maggie's is better. I also have a tote bag and a cup, but the cup was designed for a project we were promoting and included a graphic used without permission. I intended to either ask the graphic owner to pay the Mars Society for advertising, or find another project name. The project has practically died but I haven't removed the cup yet; but I haven't sold any cups anyway. There are other items I could add to the store: wall calendar, poster calendar, greeting card, postcard, picture frame, infant/toddler T-Shirt, toddler button-up hoodie, sticker (rectangular or oval), lunch box, various mugs (ceramic, stein, frosted, stainless steel travel mug), tile coaster, round wall clock, "flying disk" (Frisbee), poster (16x20 or 23x35), bags with a 4"x2" imprintable patch (unistrap, backpack, or soft briefcase), or a license plate frame. All I need for any of these is a graphic to print on them.
There isn't a bumper sticker but all I need for the frame is a slogan. I don't want to steal Maggie's slogan without permission. Would you like one that simply says "The Mars Society" on top and the web site address on the bottom, perhaps with a Mars terrain background image from Mars Global Surveyor?
NASA is strongly about education; but most importantly NASA means no combat, period.
Actually I had this argument with a business partner a few years ago. He produced virtual reality systems and had a very simple first person shooter that he setup for a major beer company. The deal was a free play for each beer you buy. That sold a lot of beer, so the beer company paid him to setup his system at every fair or exposition. But he then had IMAX ask him to create a family oriented game to be played in the lobby of their theaters. He couldn't think of any so he asked me and my associates to design a game for his system. I came up with a space rescue: the ISS has been hit by a meteor storm and it's your job to fly the Space Shuttle and rescue the astronauts. As a competition, a second system could fly a Soyuz to rescue cosmonauts from Mir. He didn't like it because it didn't have shooting. I don't think he understood what IMAX meant when they said "family oriented". He didn't get the IMAX contract because he couldn't design a family oriented game. It turned out the scheduled release date was the same month as the accident on Mir. Now that would have gained some attention.