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He can try it. I’ve heard that criticism before. I think it is more important for him to be natural then act. I would rather Zubrin be conformable, then have dry eyes and be uncomfortable. Maybe eye drops and muscle relaxes before television would help.
Sad that such a small thing can hurt the message of such a great man.
I support Dr. Zubrin and his ideas as much or more than anyone. But he does something that hurts his television appearences and public presentations.
He blinks too much.
When Arnold Shwartneggar was running for governor, a campaign consultant happened to mention that one of his great strengths was that he rarely blinked. The consultant also pointed out that President Bush had trained himself not to blink during an entire 30 second sequence (try it, its hard to avoid).
The consultant said that studies show that lack of blinking calms an audience and reassures them while excessive blinking unnerves people.
Perhaps it would help Mars Direct if Dr. Zubrin would blink less.
Can't hurt.
Twelve might be pushing it crew wise.
With a Gas Core NTR rocket, the mass wouldn't be too outlandish.
What do you think the mass leaving LEO would be?
And what would total mission duration be probably?
I thought five and a half years with about a 4.4 years total transit time and 1.2 years there.
But I could be wrong.
"I've conceded that I would use a larger booster for Mars Direct and go to a five man crew. But expecting more early on is asking too much."
But its NOT asking that much more! If you have the superbooster or abandon the direct-flight requirement with 1960's tech NTR engines, you can reach payload masses large enough for a practical, sustained base. This is not an impossible joke like Bush-I's SEI! It would likly cost no more then the stupid ISS does... The difference in capabilities required between MarsDirect and what are needed for small-scale perminant habitation are simply not all that large.
I do not care about a base on Mars. Nor do I care about developing new technology to make the missions easier and more efficient.
Nor I suspect do most of the American people, Congress or any administration.
Sure it would be nice, and if we can develop one as an extension of long duration Martian stay times (40 months instead of 18 on the surface) then fine. That would be great.
All I and I suspect most people care about it getting a manned AMERICAN crew to Mars and safely back AS SOON AS POSSIBLE as CHEAPLY as possible.
First, lets get a crew to Mars and back, break the ice (politically, beauracratically, and all that) and then develop things from there.
We get the first couple of manned missions....THEN we can work on making sure it all doesn't die like Apollo.
Alot of people think that the design reference mission is simply NASAs way of making the mission too complicated to do at all. Because NASA as an institution has no interest in Mars.
I think GSN that you're expecting too much of the first manned mission to Mars.
I've conceded that I would use a larger booster for Mars Direct and go to a five man crew. But expecting more early on is asking too much.
A crew of five on Mars would be able to do one hell of alot of science in 18 months. Even with a rather spare equipment loadout.
And whether we go with bare bones Mars Direct or a "Battlestar Galactica" sized mission, ANY program can be canceled by the U.S. or fail to capture the imagination of the American public.
You simply CANNOT build a program "too big to abandon".
Say you wanted to deliver a 100 ton spacecraft to Callisto.
Assume you use water on Callisto to produce both return fuel and for personal use.
Assume you have nuclear rocket engines of the type we could reasonably expect to build within the next 20 years.
How much mass would you initially start with from LEO?
Note: Assume crew of twelve.
And what would the total mission duration likely be?
I keep bringing the Saturns because I've read in more than one place that five F-1s are still in storage in good condition and can easily be used to reverse engineer newly manufactured and upgraded F-1s.
And I read that the company that owns them (it is still Rocketdyne?) has said they could resume F-1 production in just 18 months from the "go" decision.
What is the thrust rating for the RS-68 by the way?
Isn't it the second most power liquid fuel rocket engine ever produced by the United States? Second only to the F-1
If we wanted to send five humans to Mars and back using the Mars Direct mission architecture and wanted to use a booster capable of lifting 200 metric tons into LEO (about 450,000 lbs-I don't know how that translates into payload to Martian surface) which would it be cheaper to build.
The "Comet" variant of the Saturn V-basically the Saturn V core vehicle with F-1 engined strap on boosters,
or
A "super" variant of the Ares launch vehicle. At least four extra segment SRBs around an external tank derived core with 4 to 6 RS-68s (is that the right designation?) engines.
Which would be cheaper to develop, build, mass produce and man rate?
Much has been said recently about how losing a crew during a manned mission to Mars would be disastrous.
How so? We' ve lost two space shuttles now with all aboard and there has been MINIMAL erosion of public support for a manned space program.
A few years ago, someone warned that if another space shuttle was lost that it would be the last time NASA flew. Yet we are probably just a few months from a return to flight now.
I think lots of space advocates have gotten tremendously cynical about public support. Yet I think that the American public have come to "expect" manned space exploration and make allowances for the risk.
Losing a crew on Mars or en route would probably just stimulate public support in the short term.
In addition my thinking is this:
If you are willing to limit the crew to four (or at most five) then Mars Direct is the best mission plan. If you want to go with a crew of six or more, chances are that Semi-Direct or Hybrid Direct will be the only way to go because of the difficulting in lifting large enough Earth Return Vehicle to the surface of Mars with one launch to support a larger crew.
The only way to lift enough to Mars using the two launches of Mars Direct for a six man crew is probably by using a nuclear thermal rocket third stage.
NASAs reference mission (basically Mars Semi-Direct) uses one launch to put a Mars Ascent Vehicle on the Martian surface.
The MAV uses in situ fuel production to produce the fuel to ascend to Mars orbit for rendevous with the methane/oxygen fueled Earth Return Vehicle.
The reason for this is that if in situ fuel production fails on the Martian surface, the entire mission can still be saved by using another launch to deliver a FULLY FUELED Mars Ascent Vehicle to the surface (without sending the equipment that went down with the original MAV).
But the Mars Semi-Direct and NASA Reference Plan was always to send the Earth Return Vehicle to Mars orbit FULLY FUELED.
Now, Mars "Hybrid-Direct" is to send only the Earth Return Life Support Cabin and Reentry Vehicle to Mars orbit. In this plan, the Mars Ascent Vehicle manufactures ALL the fuel needed to ascend from Mars AND RETURN to Earth.
Dr. Robert Zubrin once said that Mars Hybrid Direct has all the disadvantages of both Direct and Semi-Direct.
The only advantage is that the Earth Return Vehicle Cabin and Reentry Vehicle can be considerably larger than in either of the other plans.
I still think Mars Direct is by far the best option.
You can hold conversations with people from Earth. They'll just be more akin to email than face to face.
And how many astronauts and cosmonauts have been exposed to zero G for more than six months? Dozens I believe. Shannon Lucid WALKED off the space shuttle after six months in space.
I think the "hero factor" will last at least for the first two or three missions.
By the time those are over, alot of the dangers associated with the missions will be reduced (thus reducing stress) and we'll either have enough public and political support to expand the missions with NTR technoloyg....
...or the program will be dead.
Either way, the human factors problem will be lessened.
I think all the whining about astronauts staying sane on a 2 and a half year mission to Mars and back are vastly overstated.
Do we really think that four (or six) astronauts can't live and work in close proximity for that long on a mission they know that will make them legends? Placeholders in history?
I mean come on. They'll never be more than 40 minutes or so from contact with Earth. They'll be getting news, personal vidoe and text messages from loved ones every hour of the day probably.
I would wager that the first astronauts on Mars will end up restricting the amount of time they talk to Earth because the shear mass of calls and inquiries will consume so much of their time.
While they are on Mars, they'll probably be working like sled dogs for months on end. Alot of it serious physical labor.
Few things keep people cooperating like lots of hard work.
On the six month trip home, sure they'll be pretty confined, but they'll have time to rest from their long exertions, look forward to their coming celebrity status and communications with home will become ever shorter in lead times.
So why do people carp about "human factors" so much?
I think any future manned Mars program the U.S. participates in should, at least in the beginning be a solely American program.
Because I believe that American public support for the project will decline as international involvement grows.
And be honest, does ESA, the Japanese, Chinese, or Russians have any technology or experience in manned space exploration that the United States really lacks?
Sure the Russians kept astronauts up for a year or so at a time, but we've had some up for six months. And I've always heard that there is little to be learned about long duration stays after the six month mark.
To me, recovering and reusing launcher equipment used in the Mars Direct architecture makes little sense.
Reuse only makes sense if you have a large sustained launch rate.
An ongoing Mars exploration using Mars Direct would only mean an average of one heavy lift vehicle launched each year.
Even if you had long duration lunar missions based on Mars Direct, that would only add two launches per year.l
I don't think three launches per year justifies recovery and reuse of hardware.
And I"m tired of people putting down Apollo. Apollo was a great program. The basic Apollo Hardware provided 75% of the hardware needed to send a manned mission to Mars even back then not to mention giving us our first space station. And alot of good work was done in Skylab.
Not to mention that the scientific data returned by Apollo exceeded many times over all the data on the moon gathered before or since by unmanned probes.;
Actually, designing the mission around the launcher IS the way things have always been done.
The Saturn V design was frozen BEFORE the Apollo mission architecture was even decided upon.
I stand by my preference. Basic Mars Direct with a 5th crewman launched by NASA "Comet" Saturn V variant which should improve mass margins significantly over the Ares launched Mars Direct.
I'm fully comfortable with the mission carrying less than a ton of scientific instruments. I'm sure there will be plenty of work to do over the 500 days on the Martian surface with that scientific suite.
We can't keep changing the mission architecture. Mars Direct was estimated to cost $30 billion for 7 missions in 1990, although in public Robert Zubrin keeps saying $20 billion for an unspecified number of missions. NASA's Design Reference Mission was estimated at $55 billion. That's significant cost creep,
No, thats not cost creep.
The NASA Refence Mission is Mars "Semi-Direct" requiring three launches instead of two (SIX if we don't develop the Ares launcher).
And the NASA mission has a six man crew as opposed to basic Mars Direct four. So that is a major upscaling of the mass necessary to send to Mars.
Personally, I agree with Zubrin that in reality a Mars mission should only cost a 6 to 8 billion or so. Triple that for the usual government inefficiency and you've still got a manned Mars program for less than 30 billion dollars.
Launch costs are a huge part of putting unmanned probes on the way.
If we're going to test launch a huge, multi billion dollar to develop booster, it makes sense to me to take advantage of the lift capabilty
Jupiter is the next stop after Mars, but we'll need a pretty highly advanced electric engine or somthing even more exotic to go that far in a reasonable time frame.
NEO, venus and maybe murcury
Lack of resources to utilize in situ on an NEO or Mercury.
We won't land a manned mission on the Venusian surface until we have armored exoskeletons to help protect astronauts.
Callisto has ice. So we can easily get hydrogen, oxygen, and of course water. Reduces the mission logistics tail.
I suspect that JIMO and a Europa probe will be the last of the unmanned Jovian missions.
Titan is arguably, the most hospitable place in the solar system aside from Earth.
Surface conditions and available resources will determine our destinations alot more than time and distance.
I've always been curious about how a manned expedition to Callisto with a landing there and telerobotic exploration of the remainder of the Jupiter system would shape up.
I assume nuclear electric propulsion would be ready by the time we went to Jupiter meaning a one way trip of 2.2 years.
How long would the total mission last? 5 & 1/2 years or so?
And what about a similiar mission to Titan?
I've always assumed that in exploring Jupiter or Saturn that we would send crews of at least 12 to each.
I'm still hoping the U.S. sends missions that far during my lifetime (I'm 37).
Any thoughts? And yeah, I know this forum is about Mars, but we shouldn't be limited in the discussion to one planet.
I guess we'll have to agree to disagree.
The problem for me is that almost everyone here sounds like a lawyer or an engineer, with an adversion for risk that borders on the ridiculous.
If we ever explore space, meaning go beyond Earth orbit, then we're going to have to take some really bold gambles.
Look, as far as I'm concerned, a 10% chance of astronaut death during the mission and a 20% chance of mission failure (ie, they fail to land on Mars or are force to abandon most of their samples and data) are ACCEPTABLE risks.
And I would wager that you would still get HUNDREDS of very qualified astronauts volunteering.
Also, I'll submit that reducing the danger of space missions has also had the effect of reducing public support as well.
I would like to note that the Apollo 17 geologist, Harrison Schmidt I believe, in a recent issue of Popular Mechanics estimated that a heavy lift launch vehicle derived from the Saturn V could be developed with a few years for only five billion dollars with twice the lift capacity of the Saturn V.
I assume he was referring to the Comet design.
Yes people.
We all KNOW it would be great to have nuclear thermal propulsion for TMI.
We all know that it would be nice to have a huge mass margin and a large crew complement. I think if we could have a twelve man crew with full sized labs and long range rovers, and even manned hoppers it would be great.
We all know that it would be nice to have massive layers of radiation shielding so that the crew didn't absorb any more than an airliner crew.
We all wish we had a great, well planned manned Mars program that was part of a larger manned program that included a continous stay on the moon, in LEO, missions to near Earth asteroids, a bigger unmanned program.....
We all wish we had solid support from the President and Congress.
We all wish we had fanatical public support.
Friends.
WE ARE NOT GOING TO GET IT!!!
Not one of those. Not now, probably not ever.
If we get a manned mission to Mars, it is almost certainly going to have to be Apollo style. A quick, dirty effort with an incredibly tight timetable and most of the science done on the margins.
Is such a program worth it?
I believe so.
If we lobby hard and get two or three manned missions to Mars over a period of 5 to 8 years or so....EVEN IF Mars gets effectively abandoned for a few decades afterwards (and I think we might be able to avoid that) I think the effort and the return on the time and money will be worth it.
I would be interested in hearing them?
Do you have suggestions as to crew size? booster type? as well.
Longer stay is the big one. I forget does mars semi direct have an interplantary transfer vehicle like the triton. I also would seriously look at the possiblity of refulling from marses moons. I like the idea of having a mobile base but I worry it might be too big. It is either that or a reasonable MAV. I would like to see the same crew able to explore large areas of the Martian landscape. I think initially research is a high priority because self sufficiency won’t be ready for at least 20 years after the first landing.
I think 18 months is long enough for the first crew.
After all, they will be global celebrities so the space program can get more use out of them here than on Mars.
Mars Direct is two vehicles basically for each mission.
A Habitat Vehicle that the crew flies in to Mars and lives in while there.
An an Earth Return Vehicle that flies straight from the surface of Mars till it aerobrakes at Earth.