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In order to deal with toxic propellants such as hydrazine, the Aerospace Engineers need to get in touch with some very good Chemical Process Engineers or experienced chemical plant managers. I worked with huge quantities of Hydrazine at times and am still kicking around. In chemical process industry, and using big plant scale reactors, a step is taken in addition of hydrazine to the reactors called "blowing down the transfer lines," which uses high pressure Nitrogen or Argon to literally blow out the lines from all residual reagents. Worried about the rocket motor having hydrazine residues dripping out? Blow down the lines and remove all vestiges from the motor. Yes, here on Earth that would contaminate the immediate area temporarily, but on the Moon, it would undoubtedly evaporate and vanish. Ditto Mars. Cleanup of Hydrazine contaminated equipment is easily accomplished with ordinary household bleach--Sodium Hypochlorite solution. Standard treatment for Hydrazine spills in the chemical industry. In my plant, we normally had at least two 55 gallon drums of hydrazine on hand almost all the time. We also had 6 drums of double strength Sodium Hypochlorite solution stored in the event of a Hydrazine spill. We also had full face mask chemical protection with cartridges specific to nitrogenous bases. My wife, in addition to being a Case Institute of Technology Chemistry graduate, was also a highly skilled plant process chemist and operator. In 24 years of operation, we suffered ZERO lost time incidents w/r Hydrazine and doing chemistry with it. And no EPA reportable incidents, either.
For those wondering about toxic propellants, i.e. Hydrazine and NTO:
As a retired chemist, these compounds are not that big a deal if good handling practices are used.
I happen to disagree that Mars is premature at this time. In contrast to the Moon, Mars has some resources which may be exploited with less energy and uncertainty. I particularly like the diurnal cycle of Mars a lot better, as well as reduced exposure to damaging radiation via the thin but measureable atmosphere. Mr. Big is laying out a sales pitch...
GW-
You are absolutely correct: Theory Guides, but Experiment Decides...a truism for a long time.
GW-
If this is simply a reprisal of Apollo 8, and not a landing; knock off the 500 kg for samples. That could be another crew member, or simply a larger margin of safety (additional fuel/oxidizer).
All Blue Origin has currently flying is the suborbital New Shepard; they have a long way to go before they begin flying the New Glenn. I'm just guessing, but maybe a static test of components in a year, first test flight in maybe 2 years? First flight to orbit in 3? Man rated in 5? Pretty optimistic.
The main problem here is having 2 closely related threads going at the same time: Apollo 8 Redux, along with the present one. So...I plead "Guilty" for somewhat mixing and confusing the topics, since one mission is strictly a Fly-By, a simple loop flown around the Moon, whereas the other, Apollo 8 Redux, requires entering circumlunar orbit. My mission architecture was postulation of how the Fly-By could be modified into the Circumlunar Orbit variety.
GW-
An interesting concept would require use of another component in the system: the Russian-built Proton M 3rd stage. Here are the details:
Type: Storable Propellant Stage
Inert Mass: 4,185 kg
Diameter: 4.14 meters
Length: 6.5 meters
Propellant: UDMH
Oxidizer: NTO
Fuel & Ox: 46,562 kg
Total thrust:613.8kN
Burn time: 238 seconds
Isp(vac): 325 seconds
My suggested model incorporates the Falcon 2 + Trunk, + dry Proton M 3rd stage to ~20,000kg, including upgraded onboard fuel for retro propulsive landing on Earth. I'm figuring on a delta V around 3.5 km/sec for the rocket equation. This gives a mass ratio of ~ 3.0.
If we configure the Dragon 2 for a crew of 4, with onboard supplies for food, an atmosphere purifier, no water recycling at 11,000 kg, adding tankage and additional fuel over and above the "normal" 1900 kg at 3,800 kg (total fuel = 5,700 kg), the empty mass of the Proton M 3rd stage at 4,185 kg, and a trunk with a motor at 1500 kg, we get a payload mass of 20,485 kg. Fully fueled, this results in a total "wet" rocket mass of 67,047 kg with a mass ratio of 3.27. This implies there will be fuel remaining after departure for insertion into Lunar orbit. The increased fuel for the Dragon capsule also implies sufficient fuel for de-orbit burn and adequate fuel for dry land propulsive landing.
This is not the calculation of a sophisticated aerospace engineer, just an amateur. Please make comments! This requires orbital assembly and 2 loads to LEO. The mass of the Proton M 3rd stage is well within the capability of the Falcon Heavy.
Some of the numbers I've seen published state the spacecraft will have a maximum distance of 400,000 miles from Earth before the inexorable forces of gravity take over and bring it back to the surface. What an unimaginable view they will have of the Moon silhouetted against the Earth? Probably the most fantastic "tourist trip" ever conceived?
kbd512-
I cannot really disagree with most of your diatribe, and in fact your positions on most of the issues mirror mine. But maybe I'm even a bit more cynical than you about some of the scientists involved; politics has interjected itself into the scientific community in a way that's destructive to science and the integrity of the researchers. Politicians know the workings of the pay to play game well, and have in many cases foisted it onto workers in the area of climate science. "Give us the results we want, or well find another player." Politics has destroyed the integrity of many involved.
I'll bet no one here has ever heard of Dr. Art Robinson, Oregon Institute of Science and Medicine? He has assembled a petition of scientists, veterinarians, and physicians who oppose the concept of Global Warming, and submitted this to the U.S. Congress. Naturally it was suppressed, even though it contained over 54,000 signatures including many Nobel Laureates. The most impressive name he had on the petition was Dr. Edward Teller, father of the Hydrogen Bomb. Dr. Robinson was formerly the director of the Linus Pauling Institute in Palo Alto, CA. He personally directed almost all the research done on Vitamin C, but had a falling out with Linus over research which indicated Vitamin C accelerated the growth of malignant cells; he would NOT modify the data or conclusions, was terminated, and using funds he received from Pauling in a defamation of character lawsuit to found his own research organization. This story is NOT widely known, since secrecy was one of the requirements of receiving the settlement. Pauling is now long dead, and the story is circulating through the scientific community in which I formerly circulated. I know Dr. Robinson, and also knew Dr. R.B. Merrifield, 1984 Nobel in Chemistry (RIP), who was affiliated with Dr. Robinson. I use this example not only to dump on the Global Warming story, but to also indicate the duplicity of motives of even the most famous scientists.
There's something called "Integrity," which seems to be in short supply.
There has been an announcement that there will be an unmanned version carried out before the manned flight. Can't remember which of the space websites reported this but it was a quote from Elon Musk.
Oops! The comment was there will be retro-propulsive landings done in advance of the mission.
kbd512-
Check out a new thread I started this morning in the Free Chat section, entitled When Science becomes Perverted by Politics. I posted my thoughts on "Global Warming" there. Just trying to allow this thread to move forward without seeing any animosity develop.
There have been comments on several other threads as to whether NASA should maintain a role in Earth Science observations, based on the premise that they need to keep monitoring "Global Warming," which has subsequently been morphed into "Climate Change." Over the past 8 years, we've heard a drumbeat of steady propaganda emanating from the White House, the EPA, NOAA, and yes, NASA about the "danger to mankind" from Human Induced Climate Change.
Before I launch into my statements and observations, let me toss out a few qualifiers about my background. In addition to being a retired Ph.D. Physical Chemist and Biochemist, I've had a lifelong hobby and deep interest in Astronomy; in fact it was my first choice for a career, but I wasn't able to pursue that dream. I also am something of a amateur archaeologist and have attended several programs involving working on various "digs' in the American Desert Southwest.
As my astronomy background calls out for me to point out a MAJOR flaw in all the hysterical climate change and Global Warming fantasies: The Sun is a LONG TERM VARIABLE STAR. The solar output isn't constant as embedded in the computer models that the climate change promoters point to. The cycle is approximately 900-950 years maximum to maximum. This is generally reflected in sunspot numbers which have now been recorded for ~ 400 years. Beginning in the early 1600's the sunspots have been observed telescopically and accurate data is available. The absolute sunspot low was recorded in the 1670's, a period which is called the Maunder Minimum. The rivers in Europe remained frozen even into the Summers, and this was commented upon by no less than Sir Isaac Newton. Fast forward to the 1990's. Sunspots were at a record high in numbers, but since 2000, have been declining rapidly, along with the un-doctored Global Temperature readings. However, due to a Political Agenda, scientists have been pressured to make the data fit with this agenda. Scientists at NOAA have been "caught faking data," recently. The University of East Anglia was caught and admonished for faking climate data. How can scientists be pressured to do things like this? Grant funding. Data the "powers that be" don't like? No grant renewals. At NASA, there are also scientists whose jobs depend on satellite observation of icepack, etc. and they sure do like remaining employed; ergo, "melting polar caps." "Melting Glaciers."
Archaeological evidence: Back in 2005, my late wife and I went to a place called "Crow Canyon Archaeological Center," and participated in an excavation of Goodman Point Pueblo near Mesa Verde, and as part of the program went through substantial laboratory training.
What jumped out at me immediately when learning about the science of dendrochronology (tree ring interpretation) was the fact that it gives an unbroken record of climate data extending back to ~ 850 AD, since the national Park has structures that old and there's a complete record of overlapping sample covering the period. The solar sunspot maximum in ~ 1100-1150 AD is mirrored by extremely small growth of trees and low rainfall in that period, reflecting near drought conditions. The Maunder minimum was also reflected by good tree ring data.
So--my "take" on the hypothesis of "Global Warming," or "Climate Change," is yes, there are these observables, but aren't "brought about by human activity." They are natural phenomena independent of humans.
QED.
kbd512-
I haven't been around here long enough to know whether or not there's a Global Warming?/Climate Change? thread around?
Anyway, I'm in complete agreement with your statements in that regard. I'll say no more here in order to not arouse the ire of the moderators. There's a long and sordid history of the University of East Anglia "doctoring data," in order to make it fit the desired hypothesis.
If we can start a thread discussing this I have LOTS of input here!
I was initially trying to use existing hardware for everything in my modelling, but as usual, mass is the killer. I was looking at the availability of MMH/NTO fueled vehicles, and there are some components in the Russian Proton M that might have some promise for incorporation. For an EDS stage, the SpaceX Falcon 2nd stage could be used, but would be difficult to get to orbit; if it were only partially fueled, it would still be able to provide a big delta V to my 35,000kg ship, which now would need to incorporate a MMH/NTO fuel system and motor(s). The ERV would need to be ISPP to LMO, and meet a fully fueled Proton M 3rd stage and 4th stage for TED (Trans Earth Departure). Alternatively, a truncated falcon second stage with reduced fuel capacity and lower mass could be used for the EDS. Back to the drawing board (and calculator!).
Well, a lot depends on the ambient temperature and thus, rate of heat transfer to the cryogen tank. In deep space, I wouldn't expect the rate to be very high, provided the tank be shaded from the Sun. As always, "the devil is in the details."
GW-
Looking at your numbers really points out why using ISPP is nearly essential to success of a Mars landing and Earth return. The mission architecture I espoused elsewhere concentrated on using an entirely methylox set of vehicles for that reason alone. Yes, MMH and NTO are very advantageous for really long term storage. What is the boil off rate of LOX from a deep space vehicle, anyway? LCH4 should be less problematic.
I'm with GW on this issue, guys! When I speak of Political Will, it simply refers to the willingness to spend the $$$$ necessary to accomplish the goals established by scientists.
For use in the real world--hydrogen peroxide is a no-go, and that's coming from a chemical professional with over 50 years in the Chemical industry! On paper, it looks great, but on paper it will remain. No serious chemist would ever suggest using the stuff. The Germans used it to power their Me 163 rocket fighters along with a hydrazine fuel. They blew up a lot of them while sitting on the ground, during takeoff, and from the residues during landings. I may be an idiot to be willing to ride in a rocket powered rocket, or airplane, but NOT if it has H2O2 in the system---anywhere!
N2O4 is toxic and corrosive. Monomethylhydrazine (MMH) is "only" poisonous, and exposure usually results in severe liver damage. The methlox couple is favored now because it has an excellent Isp, and in the Raptor engine is hypothecated to deliver 383 sec. This is second only toH2/LOX. Fewer problems with Methylox than H2/LOX.
I wasn't proposing a landing ON the 4th, but trying to at least make it in 2026. There is a Hohmann transfer window in 2024, so there could be a on-Mars celebration of our nations 250th birthday.
kbd512-
I'm not disagreeing with your overall mission concept--only stating that it seems misplaced here and lost in the shuffle.
I have proposed an architecture that also requires multiple Falcon Heavy launches. Overlooked in the shuffle sometimes is the simple fact that RP-1 fuelled vehicles cannot be used on long missions; RP-1 has terrible thermal properties, in that it gels up like Jello below minus 35 degrees C. We need to utilize a new 2nd stage--one using the methylox couple. That is subsequently completely compatible with a Mars landing and the Zubrin proposed Sabatier reaction for fuel production. See my model for a mission architecture on the Mars Direct, Mars Semidirect, etc. thread.
As I was listening/watching last night's Presidential Address to the Congress of the United States, President Trump mentioned something that I had not been thinking about: our Nations 250th Birthday. He also mentioned in passing, the possibility of footprints on the ground on another planet. I suspect he isn't referring to the Moon, either. What finer way for us to truly celebrate this momentous date than by memorializing the birth of our nation, than by a Mars Landing? Funny how things seem to coincide in time with a National ability? That's obviously outside NASA's present timeline, but not that of SpaceX!
I see this date, 4 July 2026, as a great goal and an opportunity to galvanize the political will in order to undertake such an endeavor. Yes, Political Will has a way of evaporating, as demonstrated by the last administration's cancellation of the Constellation Project. OK, maybe it wasn't a great idea, and lacked sufficient funding to get it done. But...after floundering around in LEO for the past 40 years, we finally have a rallying point for exertion of a new statement of Political Will. Or DO we?