Author Topic: Mars sample return  (Read 13610 times)

Offline vjkane

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Re: Mars sample return
« Reply #20 on: 01/01/2018 08:47 PM »
On the positive (but unexplored) side, here's a thought on how to deal with the generic case of sample return (not just Mars).

Structure a CRS-like program which bids out "return from on orbit somewhere", where each mission needs to start, be on station for a duration, and return in certain conditions. Offer a number of overlapping "slots" for N providers to bid on, and two to fly.
There are proposals for doing a number of lunar sample returns, and I could see this model working well there (nearby, multiple flights, etc.), especially if the samples are bulk samples gathered directly by an arm on the lander.  At least one credible design for a lunar bulk sampler would cost less than $850 M without the launch (the New Frontiers proposed lander).  With a bulk purchase, this would likely go down on a per flight basis.

With Mars, I'd believe this would be harder.  First, there's a need for a highly capable rover with very sensitive instruments to go find the right samples scattered across a fairly large landscape.  The scientific community rejected the concept of simply collecting bulk samples from the immediate landing site they are looking for very specific and usually rare geologic setting.  Hence the need for a highly capable rover.  The sampling mechanism and caching system are proving to be challenging to design.  Also, intelligently selecting those samples makes this a science mission, and I'm not aware of private companies with the proven expertise to run complex science operations of this nature.  In addition, Mars presents some problems in terms of storing fuels on the surface because of the cold.  One of the key breakthroughs that NASA believes would enable a Mars sample return next decade is a fuel type that can withstand that cold.

As I said, I think the technical capabilities of private companies to mount their own missions outside of NASA's R&D structures, have matured to the point where lunar missions are credible.  Mars appears to be too far away and too technically challenging at this point for it not be an R&D exercise and not to require extensive interaction with a science team.  The same could probably be said of comets at this point.

Probably the biggest challenge to this idea is that so far no government has been willing to fund a series of missions that could be built on an assembly line where the strengths of the private sector shine best.  With one-off missions, they are R&D efforts and NASA wants to work intensely with the industrial or agency labs doing the design and testing.  If you are committed to doing ten flights, one or two failures are acceptable.  If you are doing this once and Congress is watching, you want that one time to succeed.

Another challenge is that planetary missions including sample return missions are science driven and exploratory.  For Bennu, as an example, there will be over a year of studying the asteroid before taking a sample.  Would a CRS-like approach where the capabilities, design, and operation involve working with large and complex science teams?

All that said, I'd like to see the CRS approach tried, and I hope it is with the moon.

Offline Space Ghost 1962

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Re: Mars sample return
« Reply #21 on: 01/01/2018 10:50 PM »
On the positive (but unexplored) side, here's a thought on how to deal with the generic case of sample return (not just Mars).

Structure a CRS-like program which bids out "return from on orbit somewhere", where each mission needs to start, be on station for a duration, and return in certain conditions. Offer a number of overlapping "slots" for N providers to bid on, and two to fly.
There are proposals for doing a number of lunar sample returns, and I could see this model working well there (nearby, multiple flights, etc.), especially if the samples are bulk samples gathered directly by an arm on the lander.  At least one credible design for a lunar bulk sampler would cost less than $850 M without the launch (the New Frontiers proposed lander).  With a bulk purchase, this would likely go down on a per flight basis.
Agree that's the easiest to demonstrate functional autonomous capability.

And the benefits are easy to see and explain to governments, in the same way that CRS benefits as well - it takes logistics out of the equation of sample conveyance. Also, since mission scope is narrowed to conveying the samples to orbit, then the whole footprint to develop is shorter/quicker/more feasible.

And the growth for exploration craft is in "feeding" the logistics chain with more and varied means/places/bodies to sample.

Even companies that wish to "piggy back" the logistics chain might be able to scope missions to leverage the capability for return.

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With Mars, I'd believe this would be harder.  First, there's a need for a highly capable rover with very sensitive instruments to go find the right samples scattered across a fairly large landscape.  The scientific community rejected the concept of simply collecting bulk samples from the immediate landing site they are looking for very specific and usually rare geologic setting.  Hence the need for a highly capable rover.  The sampling mechanism and caching system are proving to be challenging to design.  Also, intelligently selecting those samples makes this a science mission, and I'm not aware of private companies with the proven expertise to run complex science operations of this nature.
There's a conflict between logistics and exploration SC.

Doesn't need to be, as those who build those exploration SC already have (as you point out) a hard enough task to get there, find/extract/assemble the samples.

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In addition, Mars presents some problems in terms of storing fuels on the surface because of the cold.  One of the key breakthroughs that NASA believes would enable a Mars sample return next decade is a fuel type that can withstand that cold.
Also having a capable, scale-able propulsion bus on orbit allows for lower propellant sizes/margin on sample launch and recovery.

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As I said, I think the technical capabilities of private companies to mount their own missions outside of NASA's R&D structures, have matured to the point where lunar missions are credible.  Mars appears to be too far away and too technically challenging at this point for it not be an R&D exercise and not to require extensive interaction with a science team.  The same could probably be said of comets at this point.
My point is about staging logistics through an evolvable common platform, likely with multiple mission capability, that for asteroids and lunar samples can be leveraged with commercial efforts.

All that would change as the logistics platform would extend to other solar system targets would be the propulsion, communications, power and duration of the vehicle.

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Probably the biggest challenge to this idea is that so far no government has been willing to fund a series of missions that could be built on an assembly line where the strengths of the private sector shine best.  With one-off missions, they are R&D efforts and NASA wants to work intensely with the industrial or agency labs doing the design and testing.  If you are committed to doing ten flights, one or two failures are acceptable.  If you are doing this once and Congress is watching, you want that one time to succeed.
But what if the CRS model bought a batch of  "regular flights" to Mars?

So lets say its a bus that delivers smallsats/cubesats/commsats/navsats every opposition to a planet, then maneuvers to multiple sample return intercepts over the course of years, and eventually returns with samples.

Your science product would be of broad number of on orbit experiments, likely pioneering surface/atmospheric/radiation capabilities/sensing, as well as refreshing communications assets that support larger missions flown directly to destinations on other LV concurrently.

If, like with Insight/Curiosity launch delays, these bulk launches would always fly and at least keep a stream of assets/payloads flowing as an insurance policy for the flagship missions to employ when they eventually made it to Mars.

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Another challenge is that planetary missions including sample return missions are science driven and exploratory.  For Bennu, as an example, there will be over a year of studying the asteroid before taking a sample.  Would a CRS-like approach where the capabilities, design, and operation involve working with large and complex science teams?
Perhaps an evolution of the concept would work as a prepackaged return vehicle, proven in LEO/cislunar/planetary uses, that either is separately launched or piggybacked on the launch as a non-integral part of the SC?

The key benefit that makes this work as a CRS-like approach is to employ the sample return as a service that is wholly detached from the science, except for the hand-off of the sample. The CRS-like SC for return has absolutely nothing to do other than logistics on demand for science, and all they focus on is refining the bus to handle the unique additional requirements (duration, props, distance from sun, radiation exposure, mission profile) to accomplish "there and back again".

For the science team it's a form of "divide and conquer" - they don't have to add all that's needed to do the logistics (and mission overhead/management) as it's someone else's expertise than keeps evolving. And since those logistics would be based on a routinely flown bus, always the best means being used/improved for the best economics/performance. Which means more focus on science and a better, increasing capacity return.

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All that said, I'd like to see the CRS approach tried, and I hope it is with the moon.
Me too.

add:
Forgot to add that there's a tendency with MSR to squeeze development just a little bit more to accomplish it, and then fall short of anything achievable. If you will the "JWST disease".

What exploration SC have achieved phenomenally in the past two decades, and should continue to develop and achieve even more in successive decades, is at odds with something like logistical support in the "return" aspect IMHO.

Also too much rides on too few elements of resilient design. Since launch, rendezvous, and recovery are all high risk, plan that you'll need many shots to begin with. Also, since there's a successive dependency, you'll want more/multiple samples launched from the surface (highest risk), with a reused (possibly multi-caching)  on-orbit SC with excessive props to chase down / compensate for launch shortfall (with on-orbit backup to compensate for on orbit mortality losses).

Then there's the economic scaleability of employing/enhancing/refining the logistics SC on successively larger scoped missions - sample return is likely to be a key part of hundreds of future missions - why not develop that as a separate mission phase component.
« Last Edit: 01/02/2018 08:03 PM by Space Ghost 1962 »

Offline redliox

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Re: Mars sample return
« Reply #22 on: 01/01/2018 10:57 PM »
Reading into one study regarding hybrid rocket propulsion for MSR here:
http://web.stanford.edu/~cantwell/Recent_publications/Boiron_AIAA_2013-3899.pdf

A hybrid mentioned is paraffin wax and liquid oxygen.  Apparently at the right ratios it can get slightly higher than 360 seconds for specific impulse, nearly on par with methalox (not exceeding, but able to match its middle range).  It might even have a temperature tolerance able to handle at least the low if not middle latitudes of Mars.
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Offline speedevil

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Re: Mars sample return
« Reply #23 on: 01/02/2018 01:39 AM »
There is also other interesting work being done - http://forum.nasaspaceflight.com/index.php?topic=36629.msg1662576#msg1662576 - A 1kg Mars helicopter that could help lots with autonomous routing.

Greatly reduced landing costs from any vendor would utterly change designs, but may be some way out even for a 2026 launched sample return.



~1kg, ~220W, ~60cm coaxial rotor, ~3 minutes a day flight to ~100m altitude and several hundred meters traverse on integral solar.

It is unclear if this will fly on the Mars 2020 rover.
There are no further public releases after the video that I have found unfortunately. I contemplated mailing the PI, but diddn't go that far.

The above is interesting because it is almost off-the-shelf, and at the weight it is can almost be worth it if you avoid a several hundred meter traverse once. (with 2020 rover class propulsion)

« Last Edit: 01/02/2018 01:45 AM by speedevil »

Offline redliox

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Re: Mars sample return
« Reply #24 on: 01/02/2018 04:56 AM »
~1kg, ~220W, ~60cm coaxial rotor, ~3 minutes a day flight to ~100m altitude and several hundred meters traverse on integral solar.

It is unclear if this will fly on the Mars 2020 rover.
There are no further public releases after the video that I have found unfortunately. I contemplated mailing the PI, but diddn't go that far.

The above is interesting because it is almost off-the-shelf, and at the weight it is can almost be worth it if you avoid a several hundred meter traverse once. (with 2020 rover class propulsion)

If it doesn't fly on 2020 I would think it'd be quite handy in scouting human landing sites.  Mentioning it here isn't exactly on topic, but it does assist in finding nearby rocks worth sampling so it has some relevance in the overall scheme.  The low kilogram weight would mean, if you have room to accommodate those blades (which look like they get folded in some), almost any landed mission could send out one drone if not more.

Because the 2020 Rover is going to end up dictating the MSR site (in order to obviously fetch the samples), has there been any word on the landing site selection?  It's been nearly a year since the final 3 were whittled down.  The rover itself is slowly being built, and while the other 2 elements of MSR are in debate it's the first link in the chain.
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Offline AegeanBlue

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Re: Mars sample return
« Reply #25 on: 01/02/2018 07:10 AM »
If you read Squyres' book about the MERs, he mentions the 2003 Mars Sample Return mission which was supposed to launch in 2003 and get samples back following a second launch with the return architecture in 2005. What I remember from Squyres' book and from the Ulivi and Harland book was that they would use a solid launcher which was developed by the US Navy in the 1960s in a classified project and could return a coconut size sample which would be capture on orbit by a French satellite. Alas the internet does not have a good writeup of that mission and what was learned from it before it was cancelled following the twin failures of 1999. This is the best of what Google could find:

https://www.lpi.usra.edu/publications/slidesets/marslife/slide_38.html

https://www.sciencedirect.com/science/article/pii/S0094576500000850

https://www.jpl.nasa.gov/news/news.php?feature=5086

The current NASA plan shows up in several presentations on the web and has been discussed earlier. I have absolutely no idea what the SpaceX plan is supposed to be now that Red Dragon has been placed in the back burner following the cancellation of legs for the Crew Dragon. Would anyone like to propose a website or even a thread about the 2003/2005 NASA Mars Sample return, SpaceX current plan and the Chinese plan?

Offline jpo234

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Re: Mars sample return
« Reply #26 on: 01/02/2018 09:17 AM »


I have absolutely no idea what the SpaceX plan is supposed to be now that Red Dragon has been placed in the back burner following the cancellation of legs for the Crew Dragon. Would anyone like to propose a website or even a thread about the 2003/2005 NASA Mars Sample return, SpaceX current plan and the Chinese plan?

SpaceX's plan is right here: http://www.spacex.com/mars

You want to be inspired by things. You want to wake up in the morning and think the future is going to be great. That's what being a spacefaring civilization is all about. It's about believing in the future and believing the future will be better than the past. And I can't think of anything more exciting than being out there among the stars.

Offline speedevil

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Re: Mars sample return
« Reply #27 on: 01/02/2018 03:32 PM »
SpaceX's plan is right here: http://www.spacex.com/mars

It's really not.
They have stated goals for 2 BFS on mars in 2022, doing research on where ice and resources are, 4 more (2 with crew) in 2024, with that crew working on ISRU.
The implication is that they could do sample return perhaps sometime in 2026, with an actual geologist selecting the samples, but that plan is not at all fleshed out, and is so orthogonal to the goals they have that it's almost unaddressed.

There are plausible speculations that could be made - for example if they're going to do ice prospecting they want a rover for ground truth, and ... - but it's in much less detail than even the unfunded NASA proposals.

I really hope there are actually geologists on mars in 2026, but this schedule relies on so many things going right that considering more modest proposals with existing capabilities is also useful.

What might be done with a large payload on Mars, with NASA mission architecture, in the case that BFR mostly works (or new glenn) and is able to launch large payloads, but the funding is not there for SpaceXs martian ambitions is also interesting.

It is almost useless to speculate from the optimistic case for SpaceX, as once you get a geologist or ten out there with a capable car that they can drive around at insane speeds (curiosity has moved 10m/day) and return tons to earth, the question ceases to have much meaning.
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« Last Edit: 01/04/2018 06:01 AM by speedevil »

Offline RonM

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Re: Mars sample return
« Reply #28 on: 01/02/2018 04:11 PM »
I'm sure SpaceX would have a geologist on the first manned flight. Bringing back samples would be a good way to generate income, especially if government research will pay the bill.

Realistically, SpaceX is not landing a crew in 2024. BFS is an aerospace program and we all know there will be delays. So, we should get back to discussing other plans for a sample return just in case Elon is being overly optimistic again.

Offline Negan

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Re: Mars sample return
« Reply #29 on: 01/02/2018 04:26 PM »
Falcon 9H is an only rocket in next 5-10 years that will make possible to do Mars return sample.

It would certainly seem to allow a one launch architecture for the ERV and lander. I would also like to see what could happen if the 150 ton to LEO payload capability of BFR was utilized. BFR could have many, many launches under its belt by 2024. NASA might not trust BFR as a Mars lander by then, but launching into LEO should be well proven.

Edit: Subtracting the lander gives FH almost 13,000 kg for the ERV. Would there even be a need for SEP with that kind of capability?

Edit: Looks like NASA is looking at 2026 at the earliest for the lander.
« Last Edit: 01/02/2018 07:17 PM by Negan »

Offline Patchouli

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Re: Mars sample return
« Reply #30 on: 01/02/2018 05:15 PM »
Reading into one study regarding hybrid rocket propulsion for MSR here:
http://web.stanford.edu/~cantwell/Recent_publications/Boiron_AIAA_2013-3899.pdf

A hybrid mentioned is paraffin wax and liquid oxygen.  Apparently at the right ratios it can get slightly higher than 360 seconds for specific impulse, nearly on par with methalox (not exceeding, but able to match its middle range).  It might even have a temperature tolerance able to handle at least the low if not middle latitudes of Mars.

Having only one stage would greatly simplify things and eliminate a failure mode.

Offline redliox

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Re: Mars sample return
« Reply #31 on: 01/02/2018 07:56 PM »
Reading into one study regarding hybrid rocket propulsion for MSR here:
http://web.stanford.edu/~cantwell/Recent_publications/Boiron_AIAA_2013-3899.pdf

A hybrid mentioned is paraffin wax and liquid oxygen.  Apparently at the right ratios it can get slightly higher than 360 seconds for specific impulse, nearly on par with methalox (not exceeding, but able to match its middle range).  It might even have a temperature tolerance able to handle at least the low if not middle latitudes of Mars.

Having only one stage would greatly simplify things and eliminate a failure mode.

Yes and no.  You could say the trick is where you're sending the samples...

When entering orbit, you technically have to make 2 burns with each establishing the orbit's apoapsis and periapsis (farthest and closest points).  When you launch, you're establishing an initial apoapsis.  Once you reach that point, that is when you need to make the second burn to  establish the periapsis...otherwise by default it is back on the planet's surface.  This is why the space shuttle's OMS engines, Saturn V's third stage, and the majority of current second stages make additional burns well after launch...to circularize orbit and prevent an embarrassing crash on Earth; in the case of MSR we're talking about crashing back to Mars (and obviously risking ruining the samples).

Hypothetically, a large single stage could fire the samples directly away from Mars onto a path to Earth.  However you definitely need local propellant production to do this.  For the moment, we might be able to manufacture oxygen using the 2020 MOXIE experiment, otherwise it's a stretch.

If you have to settle for Mars orbit, like low orbit for the current MSR plans, 2 stages are best.  The first launches while the second circularizes the orbit in short, although most likely the second stage may help in ascent too depending how much oomph stage 1 gives.
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Offline Negan

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Re: Mars sample return
« Reply #32 on: 01/02/2018 10:03 PM »
I wonder if any of the costs have changed. From the documentation below, just the lander portion is over 3 billion (covers everything accept return from Mars orbit).

https://ia800300.us.archive.org/24/items/MarsSampleReturnLanderMissionConceptStudy/09_Mars-Sample-Return-Lander-Final.pdf
« Last Edit: 01/02/2018 10:04 PM by Negan »

Offline vjkane

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Re: Mars sample return
« Reply #33 on: 01/02/2018 10:14 PM »
I wonder if any of the costs have changed. From the documentation below, just the lander portion is over 3 billion (covers everything accept return from Mars orbit).

https://ia800300.us.archive.org/24/items/MarsSampleReturnLanderMissionConceptStudy/09_Mars-Sample-Return-Lander-Final.pdf
NASA has stated that they believe they have options that would lower costs both through different technology/design choices and through collaboration.  They have not released those.

Offline AegeanBlue

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Re: Mars sample return
« Reply #34 on: 03/08/2018 11:23 PM »
A presentation from MEXAG February 2018 meeting on MSR:

https://mepag.jpl.nasa.gov/meeting/2018-02/04_Edwards_MSRMidDecadal_MEPAG_VM1.pdf

Pretty interesting. They are actively developing hybrid propulsion for the ascent stage at Marshall

Offline Star One

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Re: Mars sample return
« Reply #35 on: 06/12/2018 07:56 PM »
NASA continues Mars sample return mission studies

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WASHINGTON — NASA doesn’t expect to make decisions on how it will carry out a Mars sample return effort until late next year despite recent discoveries that have offered additional evidence that the planet was once, and may still be, habitable.

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“Certainly, Mars sample return is something that we are committed to as an agency,” said NASA Administrator Jim Bridenstine in a June 6 briefing with reporters. “That’s a civilization-level changing capability, and we want to do it.”

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He noted that NASA’s 2019 budget proposal included $50 million to support planning for Mars sample return efforts. That funding line remained flat for later years in the budget proposal, pending development of a more detailed mission architecture.

“We’re going to give a lot more clarity about what that means exactly in the next budget cycle,” he said. However, he didn’t expect those plans to fall into place until late next year. “The first time we’re really going to start tying up things, really making decisions because we have parallel joint investigations going on in Europe as well, is late ’19. It’s not a decision this week or next week or next month.”

http://spacenews.com/nasa-continues-mars-sample-return-mission-studies/

Offline Don2

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Re: Mars sample return
« Reply #36 on: 06/13/2018 06:28 AM »
NASA is sounding fairly committed to sample return at this point.

I think that one consideration is that the Entry-Descent-Landing expertise tends to decay over time. If they launch Sample Return in 2026 that will be 6 years after the 2020 Rover. I worry that if they go later than that they might find that they have lost some of their capability to land successfully. We've had a Mars landing about every 5 years since the mid-90s, and a 2026 landing would maintain that tempo.

The other thing I was thinking about is that it would be a good idea to put a few scientific instruments on the fetch rover.  This rover will have to be capable of high speed driving. It needs to make 100m per day to be able to collect the samples in the time available. Once it has finished with the sample fetch mission, it could potentially last another 10 years and drive long distances across the surface. One interesting thing is that the Jezero Crater and NE Syrtis landing sites are within driving range of each other. Once the fetch mission is done it would be entirely possible for the fetch rover to drive to the site that wasn't selected. And it doesn't need a lot of instruments to do a useful mission. An APXS could provide bulk chemistry. An IR spectrometer could identify minerals, and a microscopic imager could study mineral grains and layers. Add a brush, and you have a simple science package that won't cost the Earth or weigh more than a few kilos.

A more ambitious plan would add a sample collecting drill and containers to the fetch rover. Why collect more samples? Firstly, the initial sample return attempt might not make it. If the fetch rover could collect samples, then there would be a spare batch of samples on the Martian surface. Even if the samples make it back to Earth, the scientists who study them are likely to want a second batch. Much will be learned from the first set of samples. The second sample collection effort could then target the most interesting areas.

@Star One ... It will  indeed be ironic if the Martians turn out to be from the same tree of life as Earthlings. There are two major families of 'bacteria', the Prokaryotes and the Archaea. Archaea tend to be found in extreme environments on Earth, so maybe they originally came from somewhere else.

Offline Star One

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Re: Mars sample return
« Reply #37 on: 06/13/2018 07:50 AM »
NASA is sounding fairly committed to sample return at this point.

I think that one consideration is that the Entry-Descent-Landing expertise tends to decay over time. If they launch Sample Return in 2026 that will be 6 years after the 2020 Rover. I worry that if they go later than that they might find that they have lost some of their capability to land successfully. We've had a Mars landing about every 5 years since the mid-90s, and a 2026 landing would maintain that tempo.

The other thing I was thinking about is that it would be a good idea to put a few scientific instruments on the fetch rover.  This rover will have to be capable of high speed driving. It needs to make 100m per day to be able to collect the samples in the time available. Once it has finished with the sample fetch mission, it could potentially last another 10 years and drive long distances across the surface. One interesting thing is that the Jezero Crater and NE Syrtis landing sites are within driving range of each other. Once the fetch mission is done it would be entirely possible for the fetch rover to drive to the site that wasn't selected. And it doesn't need a lot of instruments to do a useful mission. An APXS could provide bulk chemistry. An IR spectrometer could identify minerals, and a microscopic imager could study mineral grains and layers. Add a brush, and you have a simple science package that won't cost the Earth or weigh more than a few kilos.

A more ambitious plan would add a sample collecting drill and containers to the fetch rover. Why collect more samples? Firstly, the initial sample return attempt might not make it. If the fetch rover could collect samples, then there would be a spare batch of samples on the Martian surface. Even if the samples make it back to Earth, the scientists who study them are likely to want a second batch. Much will be learned from the first set of samples. The second sample collection effort could then target the most interesting areas.

@Star One ... It will  indeed be ironic if the Martians turn out to be from the same tree of life as Earthlings. There are two major families of 'bacteria', the Prokaryotes and the Archaea. Archaea tend to be found in extreme environments on Earth, so maybe they originally came from somewhere else.

Well we still don’t know why the change happened that allowed complex life in the first place happened as it almost seems a one in a billion chance. Maybe the ‘change factor’ came  externally.

Offline CuddlyRocket

Re: Mars sample return
« Reply #38 on: 06/13/2018 11:08 PM »
It will  indeed be ironic if the Martians turn out to be from the same tree of life as Earthlings. There are two major families of 'bacteria', the Prokaryotes and the Archaea. Archaea tend to be found in extreme environments on Earth, so maybe they originally came from somewhere else.

Both Bacteria and Archaea are Prokaryotes. Although originally found in extreme environments Archaea are actually in many habitats (including humans!). As Bacteria and Archaea have many genes in common it is believed that they have a common ancestor.

Offline Don2

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Re: Mars sample return
« Reply #39 on: 06/14/2018 12:15 AM »
Yes, that is correct, Archaea and Bacteria are both types of Prokaryotes. They are typically 1 micron in size and are thought to have evolved over 3 billion years ago. Humans are made of Eukaryotic cells, which are far bigger and more complicated and are thought to have evolved 2 billion years ago.

Is there any chance that Archaea come from Mars and Bacteria come from Earth? Is it known why Archaea and Bacteria split into two different kingdoms?

Tags: Mars