Poll

It is more than likely new techniques and equipment will be needed to optimally reach, then explore, Mars.  All have a useful purpose, but which should be the prioritized avenue?

Ion Drive
9 (10.2%)
Aerocapture/Aerobraking
13 (14.8%)
In Situ Resource Utilization
51 (58%)
Propellant Depots
15 (17%)

Total Members Voted: 88

Voting closed: 07/27/2015 11:09 AM


Author Topic: Best technology to research for Mars first  (Read 6921 times)

Offline redliox

  • Full Member
  • ****
  • Posts: 1966
  • Arizona USA
  • Liked: 397
  • Likes Given: 66
Best technology to research for Mars first
« on: 04/18/2015 11:09 AM »
A lot of new technology will be needed for a Martian expedition.  The obvious bad news is NASA is far too underfunded to invest then develop even proven systems for human-scaled needs.  Possibly other nations may assist, but for the most part they're playing "catchup" to U.S. capabilities, meaning NASA will remain the de facto leader for a while yet.

If only one of the following could be properly developed for human spaceflight, which should it be?
"Let the trails lead where they may, I will follow."
-Tigatron

Offline geza

  • Full Member
  • **
  • Posts: 242
  • Budapest
    • Géza Meszéna's web page
  • Liked: 79
  • Likes Given: 33
Re: Best technology to research for Mars first
« Reply #1 on: 04/18/2015 11:28 AM »
I know that the canonical ansver since Zubrin is ISRU. However, ISRU-lovers usually consider aerobreaking/capture as a given. If there is a choice between them, then aero--- is the more important one.

Offline R7

  • Propulsophile
  • Senior Member
  • *****
  • Posts: 2738
    • Don't worry.. we can still be fans of OSC and SNC
  • Liked: 954
  • Likes Given: 662
Re: Best technology to research for Mars first
« Reply #2 on: 04/18/2015 11:36 AM »
ISRU

The rest are fishes giving man enough food to do flags and footprints.
This is the fishing rod enabling the man to colonize.

Entirely other question is whether the big wigs are interested the latter at all.

I know that the canonical ansver since Zubrin is ISRU. However, ISRU-lovers usually consider aerobreaking/capture as a given. If there is a choice between them, then aero--- is the more important one.

For surface expedition aerobreak/capture is not even relevant because full EDL is a must.
« Last Edit: 04/18/2015 11:39 AM by R7 »
AD·ASTRA·ASTRORVM·GRATIA

Offline The Amazing Catstronaut

  • Full Member
  • ****
  • Posts: 1071
  • Arsia Mons, Mars, Sol IV, Inner Solar Solar System, Sol system.
  • Liked: 757
  • Likes Given: 627
Re: Best technology to research for Mars first
« Reply #3 on: 04/18/2015 12:59 PM »
ISRU. Not only is it mandatory for colonisation, it could prove extremely benign for certain flags n' footprints expeditions.

Apollo may have been flags and footprints, but that didn’t prevent anyone from mounting multiple expeditions throughout the course of the program. ISRU is great for cost cutting with certain mars architectures if you can reuse the same ISRU hardware between each landing.
Resident feline spaceflight expert. Knows nothing of value about human spaceflight.

Offline Russel

  • Full Member
  • ****
  • Posts: 1066
  • Liked: 110
  • Likes Given: 1
Re: Best technology to research for Mars first
« Reply #4 on: 04/18/2015 01:52 PM »
Um, I know I'm swimming against the tide here, but we don't actually need ISRU in order to get to Mars, get there sooner rather than later, get there with a minimum of development effort, get there without cutting corners, get there in a certain amount of style and do so cost effectively.

The single biggest mass saving in IMLEO terms we can make comes from aerocapture. (The second biggest comes from leaving as much mass as possible in high Mars orbit). And I've proposed doing aerobraking but only for almost-everything-but-the-crew. And I've proposed using the water that is otherwise serving as a radiation shield as a heat sink, thus considerably reducing the mass of the thermal protection system. Nevertheless it needs more study.

We also need a robust, efficient workhorse methalox engine and that's no trivial exercise. We also need long term cryo storage of at least methane/lox and that to me is a rather interesting problem in itself - particularly the long term durability of the components.

ISRU will be developed in stages but the best way to test much of it is with human attendance and thus we need to not absolutely rely upon it at least on early missions. In future it will become a big thing but not so much for transportation issues but long term life support and livability issues. Creature comforts, good food etc.

« Last Edit: 04/18/2015 01:55 PM by Russel »

Offline dkovacic

  • Full Member
  • *
  • Posts: 196
  • Liked: 42
  • Likes Given: 25
Re: Best technology to research for Mars first
« Reply #5 on: 04/18/2015 02:23 PM »
If you ignore flags and footprints as requirements, I think teleoperation/telepresence, efficient ECLSS and sample return enable near term exploration of Mars. It reduces risk and mass requirements and does not require ISRU. Also Curiosity style EDL would be enough for such type of operations.

Offline nadreck

Re: Best technology to research for Mars first
« Reply #6 on: 04/18/2015 03:31 PM »
I voted ISRU, one is that ISRU to me includes propellant depots as part of its technology. Aerocapture/Aerobraking does not require work from my perspective. We have the TPS systems alread, we have tons of lower ionosphere experience with a variety of speeds and craft. The development work for Aerocapture/Aerobraking is specific to the craft in question and not a whole new area of engineering.  I don't see Ion/SEP/NEP as gating, but along with ISRU/Depot comes long term cryo storage, and that is the first major requirement to save weight on our craft. ISRU requires it, prop depots need it, and while Earth orbit depots are not gating, many here have made good arguments in their favour. ISRU though, and the implied storage of Mars/Phobos/Deimos produced propellants, are key to reusable craft making many return flights to Mars.
It is all well and good to quote those things that made it past your confirmation bias that other people wrote, but this is a discussion board damnit! Let us know what you think! And why!

Offline Russel

  • Full Member
  • ****
  • Posts: 1066
  • Liked: 110
  • Likes Given: 1
Re: Best technology to research for Mars first
« Reply #7 on: 04/18/2015 04:23 PM »
I see ISRU as entirely separate issue to propellant depots because whatever the merits of ISRU for ascent propellant, the benefit tends to evaporate once you're in orbit.

I chose aerobraking because it was really the only option left. For me the engineering on the transit vehicle is the big challenge. And that means designing stuff that just works, and continues to work, for years.

Aerocapture might be old hat in a sense, but doing aerocapture without a big, heavy, ablative heat shield is another thing. What I'm proposing is essentially a light weight ceramic fibre thermal blanket (or the like) over a metal skin that is actively cooled. Now, that's a shade more interesting.

Offline Robotbeat

  • Senior Member
  • *****
  • Posts: 28616
  • Minnesota
  • Liked: 8585
  • Likes Given: 5600
Re: Best technology to research for Mars first
« Reply #8 on: 04/18/2015 05:10 PM »
We could do Mars without any of those things (and aerobraking shouldn't be on this list since it's already standard for Mars missions... aerocapture is a special case of aerobraking which would need a little research, but aerobraking already gets you much of the way there).

Of those things, ISRU is by far the most important and with the greatest potential, though no doubt electric propulsion is pretty low-hanging fruit.

ARM OptionB would allow you to fill up with ISRU propellent before even leaving high Earth orbit. ISRU from Phobos and the surface of Mars would then drive a stake through the heart of the exponential nature of the rocket equation in Mars exploration.

So ISRU. We can do Apollo-like missions without those things, but ISRU without a doubt is the most important.

A depot would be a great help to ISRU and would help us do missions without large launch vehicles and would also help leverage SEP for high-thrust and aerobraking could also be useful for tankers. Really, all these technologies are best when they can interact and amplify each other.
« Last Edit: 04/18/2015 05:12 PM by Robotbeat »
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline KelvinZero

  • Senior Member
  • *****
  • Posts: 3880
  • Liked: 634
  • Likes Given: 164
Re: Best technology to research for Mars first
« Reply #9 on: 04/18/2015 10:12 PM »
ISRU.. but for a sort of dishonest reason.

Firstly, because I don't think of ISRU as enabling Mars, rather Mars is only worthy because it enables ISRU. I would make ISRU the core goal of HSF.

Secondly, I extend ISRU to robotic prospecting all the low hanging fruit such as NEOs, Phobos, the lunar poles so we at least know what is there. And also to propellant storage and transfer. I think it is silly to consider an architecture without doing this basic homework so we at least know which propellant is the best choice.

However... currently we are headed for investment in larger ion drives for HSF, and some propellant depot experiments may be nearer at hand than other technologies. I am actually pretty happy with this as well. These seem like basics to me and would work very well together. Even if you dont like SEP for the crewed vehicle, SEP plus prepositioned fuel can save a lot of mass and eventually money.

Other things unmentioned were gaining confidence in a DSH for multiyear missions, and landing HSF-scale payloads on Mars. Maybe with large reusable SEP propulsion we will be able to throw larger unmanned payloads at mars every window and get the experience we need there.

Really we should be doing all these things. They would not cost much in the first place and the knowledge would not cost a lot every year just sitting around unused.

Online scienceguy

  • Regular
  • Full Member
  • ****
  • Posts: 771
  • Lethbridge, Alberta
  • Liked: 70
  • Likes Given: 144
Re: Best technology to research for Mars first
« Reply #10 on: 04/18/2015 10:14 PM »
Materials stronger than Kevlar but just as light

A more energy efficient ion drive

A lightweight fusion reactor
e^(pi*i) = -1

Offline sdsds

  • Senior Member
  • *****
  • Posts: 5479
  • "With peace and hope for all mankind."
  • Seattle
  • Liked: 581
  • Likes Given: 677
Re: Best technology to research for Mars first
« Reply #11 on: 04/19/2015 07:38 AM »
I chose propellant depots, because they most directly leverage the "game changing" capability that really might be coming soon: cheap lift.
-- sdsds --

Offline the_other_Doug

  • Senior Member
  • *****
  • Posts: 2726
  • Minneapolis, MN
  • Liked: 1786
  • Likes Given: 3387
Re: Best technology to research for Mars first
« Reply #12 on: 04/19/2015 04:56 PM »
I chose high-impulse ion drive technology, because that is the actual game-changing propulsion technology breakthrough we need to not only explore Mars but also to spread out into the solar system.  Chemical propulsion can only get us so far... literally.
-Doug  (With my shield, not yet upon it)

Offline Oli

  • Senior Member
  • *****
  • Posts: 2242
  • Liked: 425
  • Likes Given: 57
Re: Best technology to research for Mars first
« Reply #13 on: 04/19/2015 05:00 PM »
Other: EDL

From the above: Ion drive, then ISRU.

Offline spacenut

  • Senior Member
  • *****
  • Posts: 2457
  • East Alabama
  • Liked: 423
  • Likes Given: 241
Re: Best technology to research for Mars first
« Reply #14 on: 04/21/2015 05:07 PM »
I voted ISRU.  However I think for a powerful ion drive and power for Mars surface ISRU a lot of power will be needed.  That is why I think they should develop a 20 ton or smaller thorium pebble bed self contained nuclear reactor.  No overheating and meltdown.  Can't be made into bombs.  Less power than uranium or plutonium but far more than the equivalent weight of solar panels.  Less radiation breakdown problems.  24 hour operation.  A nuclear ion drive could transport a lot of tonnage of equipment to Mars.  On the surface of Mars could provide all the power you would need to operate ISRU equipment.  The pebble bed reactor should also be modular with minimum hookups and easy startup so it can be brought on line quickly, even robotically after launch.  If the total nuclear ion tug's weight is less than 50 tons, Falcon heavy to make it operational. 

A reactor unit could also be loaded onto a MCT to be delivered to Mars surface and even buried with an excavator with only the controls and contacts at the top for power on the surface.  One could also be delivered with a one way lander via the tug to Mars without an MCT. 

Also the ion drive should use argon as propellant as earth's and Mar's atmosphere contain argon, so ISRU could process the argon and compress it for launch from either Mar's or earth to refuel the ion tug. 

Offline Burninate

  • Full Member
  • ****
  • Posts: 1135
  • Liked: 352
  • Likes Given: 73
Re: Best technology to research for Mars first
« Reply #15 on: 04/21/2015 05:30 PM »
All of the above.

They're all required simultaneously to start doing realistic, affordable manned missions, unless you introduce extraordinary changes like NTRs or a tolerance for a vastly expanded launch program.
« Last Edit: 04/21/2015 05:32 PM by Burninate »

Offline sanman

  • Senior Member
  • *****
  • Posts: 4492
  • Liked: 682
  • Likes Given: 8
Re: Best technology to research for Mars first
« Reply #16 on: 04/22/2015 04:05 AM »
I picked ISRU, because it doesn't sound like MCT is even going to use propellant depots.

Offline Joffan

  • NSF Irregular
  • Full Member
  • ****
  • Posts: 1411
  • Liked: 445
  • Likes Given: 1264
Re: Best technology to research for Mars first
« Reply #17 on: 04/27/2015 05:20 PM »
Magnetoshell orbital insertion and braking would be awesome... not sure if that counts as aerocapture and braking or not.
Max Q for humanity becoming spacefaring

Offline dkovacic

  • Full Member
  • *
  • Posts: 196
  • Liked: 42
  • Likes Given: 25
Re: Best technology to research for Mars first
« Reply #18 on: 04/27/2015 05:31 PM »
It would be really awesome...and also very applicable to earth reentry.

Offline kch

  • Full Member
  • ****
  • Posts: 1764
  • Liked: 492
  • Likes Given: 8815
Re: Best technology to research for Mars first
« Reply #19 on: 04/27/2015 05:32 PM »
Magnetoshell orbital insertion and braking would be awesome... not sure if that counts as aerocapture and braking or not.

If it makes use of aerodynamic drag to slow the vehicle, why would it not count?  :)

Tags: