You are not logged in.
Why does anything think there is the slightest chance Europa is habitable given the radiation there? Why not spend more effort on exploring Callisto?
I wouldn't really call them "interstellar probes" unless they stood a chance of actually entering another solar system in operating condition
If you carefully read the NASA history of the Viking program you find all sorts of interesting things. Like how originally the program to put landers on Mars was called "Voyager" and was considered a precursor to a manned Mars landing. Mars Voyager was supposed to be launched with a Saturn V launch vehicle. But Congress in the late 1960s had turned sharply against NASA and thought that the Mars Voyager program was an attempt to get the U.S. committed to putting astronauts on Mars. This was something that Congress hated the thought of committing to given the escalating costs to the U.S. of the Great Society and the Vietnam War, thus Mars Voyager became the first planetary exploration program of NASA's killed.
Though in typical military fashion, NASA recycled the "Voyager" name for the Outer Planets Grand Tour program.
Viking thus came to replace Voyager regarding putting two landers on Mars along with two orbiters circling the planet. Almost immediately the program started running into budget problems with a dispute between "lander people" and "orbiter people". Each side wanted theirs to have the bulk of the resources and mount the most sophisticated instruments. Eventually the "lander people" won out as it was pointed out that NASA had already put spacecraft in orbit or flybys of other planets whereas aside from the Lunar Surveyor, NASA had not done so regarding landers.
Then the real battle got underway.
At first many scientists considered making high resolution pictures of the Mars surface and conducting analysis of the Martian surface and atmosphere to be the absolute highest priority. But pretty soon the advocates of searching for life on Mars gained ascendency and pretty soon the bulk of the budget and engineering resources.
This greatly annoyed many of the scientists in the first group. For one, most scientists felt the possibility of life existing on Mars much less being detected by a remote lander to be vanishingly small. Almost to the point of impossibility. Others felt it was more than a little ridiculous for the Viking landers to be tasked with searching for CURRENT signs of life when it probably be more productive to search for signs of PAST life.
Now we get into the battle over which experiments to include in the tiny Viking landers life detection module. To put it simply, Vishniac's "Wolf Trap" was consider "wet" while the three experiments actually sent were considered "dry"
"Dry" in this case is misleading. One of the life detection devices added no moisture at all to the Mars soil sample. It basically looked for life in Martian soil "as it was". It was definitely "dry". The second life detection device added the equivalent of a single drop of water to the Mars soil sample. The third life detection device (so called "chicken soup") basically saturated its Mars soil sample with a moist nutrient mixture.
But.
Contrasted to those three devices "Wolf-Trap" was definitely "wet". Wolf-Trap (a light scattering experiment) basically called for suspending the Mars soil sample in water and watching for changes in the clearness of the water. Given that bacteria growth causes water to become cloudy.
While Wolf Vishniac was able to make Wolf-Trap far lighter, cheaper, and simpler as time went on, there were concerns among the scientist that
1) Wolf-Trap would be difficult to ensure the reliability of. "Reliability" on the Mars surface being one of the Viking programs major issues.
2) Wolf-Trap would be the LEAST likely device to detect life in Martian soil as it introduced conditions that were completely unlike conditions on the Mars surface in 1976 (or in millions of years). That is being soaked in water.
Thus, Wolf-Trap was dropped from the Viking landers.
And of course this took place in an era of massive budget pressures on the Viking program. With costs skyrocketing, especially for the life detection unit.
Also there were time pressures to finalize the design of the Viking landers and get the contractors to build them. NASA already knew that when America celebrated its bicentennial in 1976 that there would be no U.S. astronauts in space. The Apollo program would be over. The Apollo Applications Program (that led to Skylab) would be over. If the space shuttle was approved, it was not expected to launch until 1977 at the earliest (it didn't launch until 1981.) Thus Viking became the program to showcase NASA during the bicentennial which meant that for a July 4th, 1976 landing (it missed this goal by more than a week due to concerns about a hazardous landing zone) that Viking I had to launch in 1975.
Building a sophisticated spacecraft and readying it for launch in barely five years is a considerable undertaking, and Viking program director knew they had to finalize their design and get on with it.
Thanks to all those factors, Wolf-Trap died
And three years later, so did Wolf Vishniac.
That was the short duration missions that required the longer return time..
Radiation from the sun as we approach we have not talked about for exposure.
We know of the cosmic exposures and what we might see on the surface of mars but thats a good question for the return.While we are flying by venus why not set up some cube sat to monitor the atmosphere and send in some atmosphere grazers that come out of the other side rather than going to the depth of the surface.
I figured but couldn't an unmanned mission do that just as capably at Venus?
Several of the older trajectories for a manned mission to Mars included an inner system swing that included a flyby of Venus. While this is not an optimal trajectory in terms of travel time to Mars and there would be concerns about elevated radiation risk, it does raise the possibility of increasing the amount of data gained by including a close recon of Venus.
Specifically what kind of scientific data could be gained by a manned flyby of Venus by a manned Mars mission?
Strictly my opinion, but "self governing" won't come until Mars becomes "self supporting" which means it is largely a question of economics rather than one of politics and governance.
If one thing in recent years regarding this issue has become clear is that governmental policies have relatively little effect on the decisions about women having children and how many they have. Government policies are way down the list on the major factors influencing those kinds of decisions. Family, culture and various other factors are far, far more prominent.
I've been interested in Wolf Vishniac and his sad fate since first reading about him in Carl Sagan's official biography.
The background for the Viking Program is truly epic all on its own.
https://history.nasa.gov/SP-4212/ch7-4.html
More about the actual program later.
Vishniac spent ten years of his life (he died at the age of 53) developing the first life detection instrument for deployment on Mars known as the "Wolf Trap".
But about 1970 or so, the Wolf-Trap was dropped for inclusion aboard the Viking landers and three somewhat simpler life detection experiments were used instead. There are indications that dropping Wolf-Trap was strictly an engineering and funding decision. The life detection module aboard the Viking landers was already the most expensive part of them by far. About 300 million in todays money. And also far and away the most complex.
How complex? The one cubic foot modules had 40,000 different parts!!!
At any rate, dropping Wolf-Trap was a huge blow to Vishniac. He had spent ten years of his life developing it and was being paid by NASA to do so. This funding was eliminated when Wolf-Trap was dropped from the landers. Even more, there are indications that while dropping Wolf-Trap was strictly an engineering and funding decision, certain people in NASA trying to retroactively justify the decision suggested that Wolf-Trap was less likely to detect life on Mars than the other experiments.
Responding to this Wolf Vishniac decided to take simplified versions of Wolf-Trap to the nearest Mars like place on Earth. Antarctica.
Vishniac had connections in the U.S. congress and managed to get approved for research trips to Antarctica despite having never taken the Arctic Survival Course required of all scientists working in Antarctica.
In 1973, Vishniac went out alone to retrieve samples.
He never returned.
He apparently strayed off the established trail and fell 500 feet down a crevasse.
Carl Sagan had a crater on Mars named after him calling Vishniac the "first casualty of Mars exploration".
It seems to me that any multi planet manned mission to the outer solar system would have to include Jupiter on the first leg of any of them.
Thus for the first Voyage to the Planets type of mission you might have
1) Jupiter (Callisto landing)
2) Saturn (Triton landing)
3) Pluto (planetary landing).
For the second Voyage to the Planets type of mission you might have
A) Jupiter (Ganymede landing).
B) Uranus (Titania landing)
C) Neptune (Triton landing).
The third Voyage to the Planets type of mission might have
A) Jupiter (Europa landing)
B) Mercury (planetary landing)
C) Venus (manned penetration of planetary atmosphere).
I assume the manned Mars program would be separate for obvious reasons.
Personally I'm not sure that reusability is the best and most needed feature for heavy lift launch vehicles. To me reusability only becomes an asset when you're looking at a substantial number of launches and the launch rate for HLLVs will tend to be rather low.
I'm not sure of the forum rules on reviving old threads and this is among the oldest I've ever revived on any forum about any subject. But I've become intrigued again by the "manned multi planet expedition" concept again.
Mars Direct is simpler, safer, and easier to pull off than DRM 3.0. The DRM was in response to MD, but added the complexity of a transfer vehicle left in Mars orbit. IIRC Zubrin spends a section in the Case for Mars discussing the problems of this approach that I won't reiterate here, but another big one that Rune didn't mention is the lack of artificial gravity on the way out. One can only speculate as to why.
.
There is one factor in favor of Mars Semi-Direct.
It allows for a mission to be salvaged without being redesigned if fuel production on the Martian surface fails for some reason. Because the Mars Ascent Vehicle is small enought that a "bare bones" one but fully pre fueled can be delivered to the Mars surface.
I have a feeling that NASA to this day is still not convinced of the viability of fuel production on the Mars surface for the first missions to Mars.
It doesn't have to cost a trillion dollars, but if its done the way NASA traditionally does such missions the costs will inflate to Epic proportions.
I am not expecting reform its ways at NASA anytime soon.Take the ISS for example. It started of with a projected cost of $8 Billion...which went to $35 Billion......$100 Billion.... and so on and so forth.
.
Apollo was only 50% over budget and it was subject to heavy time pressures. The ISS is a very bad example because it suffered from a whole slew of redesigns that occurred after metal was already being cut on the project. Including a massive redesign to bring the Russians aboard.
I've seen an estimate online that was only for 75 billion dollars including a 50% cost overrun and included the first three manned missions.
Going to Mars is no longer rocket science. It's political science.
[quot
The future does not benifit from disposable single use heavylift.
Please don't take this the wrong way.
But I don't give a rats ass about the future.
The problem with we space advocates is we keep talking, hoping, planning...praying...for a "future". that we all just know will be great and perfect in regards to space exploration.
We spend too much time on 20 years in the future and not enough on 2 years from now.
I don't care why we're getting new rockets. I don't care if its a NASA jobs program. I don't care if its to get a politician reelected.
What I care is about getting some flags and footprints in as many places as possible as soon as possible.
Focus on the present. The future will take care of itself.
All of us here should be rejoicing. Not whining.
If NASA is seriously committing to a renewed Heavy Lift launch capability, then it means we're ultimately going to see manned missions beyond Earth orbit.
No currently planned Earth orbital missions require heavy lift.
And I don't really care if the plan is to keep Lockheed or Boeing employees or NASA workers on the job.
In all fairness. George Bush #43 didn't move to Texas.
His father moved ther to strike out into the oil business when the current president was still a small boy.
google is great
http://www.chessvariants.org/multiplaye … ...ss.html
Send him an e-mail and ask. :;):
= = =
http://www.ee0r.com/tri-chess/]Martian Chess & Go
How come I can never get a search result that fast?
Blasted half decade old computer.
I was reading an old copy of Strategy & Tactics. The early version of the military wargaming magazine back when it was edited by James F. Dunigan.
It had a game review in the back for a 3-Player Chess Game by Robert Zubrin.
I was wondering if the creator of this version of Chess was created by our own Dr. Robert Zubrin?
Any idea? The issue was from 1974.
No offense, but the mission you outlined I think is undoable.
What you've outlined would take four or five separate manned missions.
Minimum.
And the stay times for a manned mission are unrealistically low given all the effort to get there.
The stay times at all the outer planets and Mars should be something like a year or more.
I've seen artwork of the proposed Ares booster.
And an article in Spaceflight showed artwork for the Saturn V derived "Comet" booster that NASA once proposed building in the 1980s.
Anyone know of any other good artwork for future proposed HLLVs of the 100 metric tons and up size?
So GCN, would you agree that Mars Semi-Direct (three launches, four astronauts) IS doable?
GCN, I was wondering if you could address the following:
1) What is your background in engineering that allows you to be so certain about Mars Direct?
2) Has Dr. Robert Zubrin or any other major Mars Direct supporter ever addressed your concerns directly?
3) You do realize that the NASA Reference Mission is basically a more complicated version of Mars Semi-Direct. Which itself is a derivative of Mars Direct. Wouldn't the NASA Reference Mission plan carry with it many of the flaws you've mentioned in Mars Direct?
After all, the NASA plan utilizes six launches (or seven) these days AND NTR propulsion
But these chances were only added to reduce the booster size to be developed. Not to increase the mass delivered to Mars surface.
4) I really think you're overlooking the political angle of a large number of flights being required for each mission.
I can just see Congressman arguing and saying "Why does this thing take seven launches for just one mission? Lets just cut that in half and save the money". "It only took one rocket to get us to the moon. And that was 40 years ago".
I mean no offense in bringing all this up. Like I've said before. I'm merely a high school history teacher and football coach.
I assume that you could use the basic Mars Semi-Direct Hab and a fully fueled version of the Mars Ascent Vehicle to bring the crew home.
I figure you could attain 80% similiarity with the Mars vehicles.
Although we don't need a trip to the moon as part of a Mars program, I think that the "side trip" to the moon is important so NASA can overcome a mental hurdle.
As someone once said IIRC "I can't see us going directly to Mars after not leaving Earth orbit for 40 years".
A superbooster of the "four SRBs, five RS-68s" variety would be pretty compatible with current launch facilities and with current manufacturers.
We don't really need the shuttles at all. The Russians can send our people and modules to the ISS alot cheaper than we can.
But keeping one for a few years might ba a more acceptable alternative than a complete shutdown.
Remember, EVERYTHING we propose must be considered from a political, social, and beauracratic context as well.
I don't believe a lunar return is necessary for a manned Mars mission.
But in order to test some key items of Mars Direct or Semi-Direct, such as the long term life suport capabilities of the Hab module I think it might be worthwhile to use Mars Direct (Semi-Direct) Hardware to send four astronauts to the lunar surface for at least a six month stay.
Besides, four astronauts staying six months on the moon could accomplish more than all the Apollo missions combined.