A Four Part Interview With Robert Zubrin

[Torquemadus]

A four part interview with Mars Society president Robert Zubrin!

[Northstar1989]

Nice! Robert Zubrin is quite a character! Do you think you could tell us a little more about what the interview focuses on in the OP, though?

Regards,

Northstar

[AngelLestat]

Thanks for the videos..

In the third video he explain why we need a manned mission. I try to explain the same in the venus concept mission but I could not do it being so brief and with such strong words.

People may differ in that, but if they really look the evidence and analize his words, they can not disagree.

[Torquemadus]

Traditional plans to go to Mars feature either the use of insanely huge interplanetary spaceships, or futuristic sci-fi technologies. Neither of these approaches offers the prospect of a Mars landing in a realistic time-frame or budget. Therefore, many claim that a Mars landing won't happen until the distant future, if at all.

Robert Zubrin developed the Mars Direct mission plan, which could be implemented in ten years, with existing technology, using a portion of NASA's existing budget. It could then be continued into a base-building phase, which would then be expanded into the first settlement. The key is that it uses the resources available on Mars to support the mission, instead of hauling everything from Earth at great expense.

The Mars Direct plan is explained in this documentary:

[PB666]

Tagging this onto the thread

https://m.youtube.com/watch?v=plTRdGF-ycs

If this guys is the salesman for the manned mars mission don't count on any footprints there soon. This guy needs to take lessons of how to give a presentation and the effect of body language on the favorabikity or unfavorabikity of the audiance with what you say. 

Most of what hes says needs to be done can be done by humans,

Life appears to have evolved on earth between 3.8 and 4.2, so that argument is wrong, and there is no evedence of fossilized macroscopic life so that is kind of a red herring argument. If life evolved in the first billion years on mars, it was likely as simple or more simple that contemporary life on earth, even if it was more complex, it would not be magnitudes more so than on earth, so that argument is kind of bogus. Or to put it otherwise if we except that the null hypothesis is no life or very simple life,mthe alterative is superterran contemporary complexity, then what is the risk reward of the research. 

The one thing i like is the drilling argument, which might need probative humans tobsearch out a drill site, given the extreme cost of deep drilling adding a few live humans does not significantly alter the risk of the mission. Thats about the only thing i agree with him on. 

Edited December 11, 2015 by PB666

[Nibb31]

A couple of things have always bugged me about the Mars Direct plan. 

First of all, what's the point of the tether induced gravity for a 6 month trip. ISS crew routinely spend 6 months in space without any major side-effects. And only the MTV ship has it, the MRV doesn't, so it can't be that essential.

Also, that MRV seems excessively small for a direct interplanetary transfer. It looks smaller than a S-IVB, while it has to contain accomodation for 4 crew members for 6 months. Also, it has a nuclear reactor on Mars, but how is it powered on the way home? 

Then, that MRV is a marvel of technology. It is quite small, yet it has to carry enough dV for a launch from Mars and the TEI burn, a couple of course corrections, and it also has to be able to reenter and land at Earth from a high-velocity trajectory. That also assumes that the heatshield doesn't suffer from being exposed to 6 months in space, a first reentry, and a year or two in Mars' surface. It also assumes that the nuclear-powered ISRU system works exactly as planned. There are all sorts of redundancy measures that need to be built-in: what happens if one of the ramps for the nuclear-reactor robot gets jammed? what happens if Martian dust clogs up the ISRU system ?

The problems aren't insurmountable, but to imagine that we can design such a spacecraft (which is much more complex than the Shuttle or even Orion) in less time, and get it all right the first time without any technology demonstrators first, is delusional.

Before you send the first man-rated MRV, you're going to need several generations of technology demonstrators to test the inflatable heatshield, the ISRU system, the life support system, etc... With a lead time of 10 years for a new vehicle, I doubt you could do it in less than 30 years on current budget constraints.

[SargeRho]

The idea with Mars Direct was to launch the ERV first, and 2 years later, the Astronauts. By the time the Astronauts launch, the ERV is already full fueled and ready for the return trip.

I did read that Zubrin's figures were excessively optimistic, and that's where Mars Semi-Direct comes from.

[Nibb31]

Yes, I think that the Semi-Direct mission was much more realistic.

[Mitchz95]

7 hours ago, Nibb31 said:

First of all, what's the point of the tether induced gravity for a 6 month trip. ISS crew routinely spend 6 months in space without any major side-effects. And only the MTV ship has it, the MRV doesn't, so it can't be that essential.

If they had no gravity during the Earth-to-Mars transfer, they'd be incapable of doing anything for at least a month (probably more) after landing on Mars while their bodies adjust to the gravity. That's less of an issue when they're going home because they can just recover on Earth the same was ISS astronauts do now.

As for the other stuff, I agree. Mars Semi-Direct is much better.

Edited December 13, 2015 by Mitchz95

[fredinno]

On December 13, 2015 at 2:17:07 AM, Nibb31 said:

A couple of things have always bugged me about the Mars Direct plan. 

First of all, what's the point of the tether induced gravity for a 6 month trip. ISS crew routinely spend 6 months in space without any major side-effects. And only the MTV ship has it, the MRV doesn't, so it can't be that essential.

Also, that MRV seems excessively small for a direct interplanetary transfer. It looks smaller than a S-IVB, while it has to contain accomodation for 4 crew members for 6 months. Also, it has a nuclear reactor on Mars, but how is it powered on the way home? 

Then, that MRV is a marvel of technology. It is quite small, yet it has to carry enough dV for a launch from Mars and the TEI burn, a couple of course corrections, and it also has to be able to reenter and land at Earth from a high-velocity trajectory. That also assumes that the heatshield doesn't suffer from being exposed to 6 months in space, a first reentry, and a year or two in Mars' surface. It also assumes that the nuclear-powered ISRU system works exactly as planned. There are all sorts of redundancy measures that need to be built-in: what happens if one of the ramps for the nuclear-reactor robot gets jammed? what happens if Martian dust clogs up the ISRU system ?

The problems aren't insurmountable, but to imagine that we can design such a spacecraft (which is much more complex than the Shuttle or even Orion) in less time, and get it all right the first time without any technology demonstrators first, is delusional.

Before you send the first man-rated MRV, you're going to need several generations of technology demonstrators to test the inflatable heatshield, the ISRU system, the life support system, etc... With a lead time of 10 years for a new vehicle, I doubt you could do it in less than 30 years on current budget constraints.

What about doing it with solar panels instead? Was that considered in with Mars Semi-Direct?

Today, though, a "Mars Semi-Direct" would probably use five SLS Block IB rockets instead (bypassing SLS Block II development).

 

The Inflatable heatshield is already undergoing testing on Earth, and will almost certainly be used in robotic Mars missions in the not-so distant future. But yeah, you need at least 2 Mars Launch windows, plus development time on Earth, to do a Mars plan.

[Nibb31]

The inflatable decelerator isn't really a heatshield. It's more of an inflatable hypersonic parachute, and it has yet to actually work properly ! The HIAD is struggling to get through TRL6, and it needs to reach TRL9 before it can used for a manned mission, which means that it needs at least a couple of actual tests on Mars probes. Since there are no plans to use it for any currently planned missions (Mars 2020 uses the same "skycrane" technique as MSL), I don't see how it could be demonstrated before at least 2025, which means that there is no way the technology can be used for a manned mission before 2030 at best.

So on that part alone, a Mars Direct mission in 10 years isn't realistic. The same is true for all the other key technologies involved, including ISRU.

Edited December 14, 2015 by Nibb31

[PB666]

11 minutes ago, Nibb31 said:

The inflatable decelerator isn't really a heatshield. It's more of an inflatable hypersonic parachute, and it has yet to actually work properly ! The HIAD is struggling to get through TRL6, and it needs to reach TRL9 before it can used for a manned mission, which means that it needs at least a couple of actual tests on Mars probes. Since there are no plans to use it for any currently planned missions (Mars 2020 uses the same "skycrane" technique as MSL), I don't see how it could be demonstrated before at least 2025, which means that there is no way the technology can be used for a manned mission before 2030 at best.

So on that part alone, a Mars Direct mission in 10 years isn't realistic. The same is true for all the other key technologies involved, including ISRU.

In a nutshell, yep. Its a great idea if you can get it to work in spades, the problem of course is getting it to work. i look that it has a turbulence problem that cannot be attenuated because of the uncertainty of the physical interactions between astmosphere and craft at the point of deployment. 

[Torquemadus]

Zubrin's thinking is that NASA went from Alan Shepard's sub-orbital flight to Apollo 11 in less than a decade. It has often been argued that the reason for this is that NASA had much more money then than it does now. While NASA's share of the federal budget is lower, the federal budget is now much larger. Adjusted for inflation, the present day NASA budget is quite similar to the average budget that was available during Apollo.

Zubrin has often quoted comments from NASA engineers, who asked: "If we could put a man on the Moon, why can't we put a man on the Moon?" and "It wasn't this hard to get to the Moon last time." Much of the perceived difficulty of sending humans to Mars is the fact that no astronauts have flown beyond LEO since 1972. The extremely drawn out and expensive development of SLS is a good example of this.

The Mars Direct plan is usually presented without mention of testing and precursor flights. This gives the impression that the hardware is flown to Mars without prior test flights. This would never be done in practice. With the exception of STS1, human rated flight hardware has always been test flown first before being flown with a crew. Un-crewed precursor flights would be flown to demonstrate that safe return of the crew is possible.

Zubrin's opening address to the 2015 Mars Society Annual Convention sets out his current thinking on the subject:-

https://youtu.be/3UChuIqIKF4