Author Topic: How many Opportunity Rovers could Falcon Heavy fly to Mars?  (Read 3570 times)

Offline Oersted

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Opportunity is heading into her thirteenth year of a three-month mission:
https://forum.nasaspaceflight.com/index.php?topic=42774.0

You should think it would make sense for SpaceX to contract the JPL to build quite a few more Mars Exploration Rovers, with just a few basic updates to solar cells, batteries and cameras, and plop them down on various locations of Mars. I cannot think it will ever be possible to make a more economical and dependable design (in view of the amazing longevity of Opportunity and to a slightly lesser extent Spirit). The science package should be focused on SpaceX' goal of identifying a good place for a colony, of course.

The Rovers that were sent in 2003 were limited to landing at certain lower altitudes of Mars. I think progress since then (low-weight heat shield, stronger parachute) would probably make it possible to target a wider variety of landing spots.

But, basically, send slightly updated versions of this time-honoured and well-proven design. How many could a FH take to Mars?

No need (and time) to re-invent the wheel when there is already a great mobile exploration rover design.

Offline IanThePineapple

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Well, I think the Martian orbiters will be used for finding the best landing spots, it would cost a LOT to build and launch a handful more rovers.
Proud creator of Ian's Paper Model Rocket Collection:
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Offline Oersted

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I added a "tag" to my posting, specifying that I am talking about the necessary ground truth that only surface assets can deliver. Of course the initial reconnaissance will be done - and already is being done - by orbital assets.

(Don't see the tag now, tho... - Maybe I didn't make it correctly)

Offline Phil Stooke

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Superficial answer:

(mass deliverable to Mars by FH)/(mass of MER in cruise configuration)

A better question would really be whether this is possible - suppose the answer was 6 MER rovers.  Do we have the downlink capability to gather the data each day, and do we have enough engineering and science people to staff six rovers at once? 

Also, is MER really the design you want?  The rovers are actually quite small.  They were enough to do the required science, but can they carry enough instruments (or experimental ISRU equipment etc.) to do what would be needed here? 

Don't get me wrong, I think it would be good to explore these issues.  But I don't think asking how many a certain rocket can deliver is really getting at the important issues.


Offline savuporo

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Don't get me wrong, I think it would be good to explore these issues.  But I don't think asking how many a certain rocket can deliver is really getting at the important issues.

Horizontal vs vertical scaling. There is room for both, and in early days of spaceflight horizontal approach was far more common, out of necessity.

Orion - the first and only manned not-too-deep-space craft

Online guckyfan

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To really get a lot done better communicaton infrastructure would do a lot. Existing orbital capabilities like high resolution photography is limited by the ability to send data back to earth.

Surface capabilities need to be a lot different than existing rovers. Bigger batteries, stationary solar arrays to recharge and the ability to cover km/day at least on known tracks.

Offline zodiacchris

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Stack the rovers in a dispenser magazine in a Red Dragon on top of a FH, land the thing in an area of interest identified by orbital assets, and have the rovers swarm out in a search pattern after deployment. That would skip the whole individual coast and EDL per rover, and would deliver high density information of 100s of square km of target area. Plus likely to be cheaper than building 6 individual spacecraft...

I'd be surprised if RDs would not take rovers of some description along, likely with some DNA of Spirit and Opportunity.  :)

Offline Oersted

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Superficial answer:

(mass deliverable to Mars by FH)/(mass of MER in cruise configuration)

A better question would really be whether this is possible - suppose the answer was 6 MER rovers.  Do we have the downlink capability to gather the data each day, and do we have enough engineering and science people to staff six rovers at once? 

Also, is MER really the design you want?  The rovers are actually quite small.  They were enough to do the required science, but can they carry enough instruments (or experimental ISRU equipment etc.) to do what would be needed here? 

Don't get me wrong, I think it would be good to explore these issues.  But I don't think asking how many a certain rocket can deliver is really getting at the important issues.

Thanks Phil, great answer!

Very true that transmission rates may be the real bottleneck. Perhaps a couple of relay satellites tagging along in the FH payload stage would alleviate the issue? Musk has already mentioned that he wants broadband and geolocation sats in orbit around Mars to help with comms and pinpoint landing capabilities. But of course that complicates the mission, and relay sats do not solve the problem of an eventual downlink bottleneck on Earth.

Something to remember before calculating how many MERs can be lofted to Mars on a Falcon Heavy is that they might very well share one single navigation stage for the coast phase. All else being equal that should make it possible to stack a few more in there. Judicious release of the various MERs from the stage in the few hours leading up to EDL should be able to ensure that their landing ellipses remain small.

In any case, Opportunity has traversed 44+ kilometes by now, and progressed well beyond its landing ellipse. The MERs are well capable of driving to a specific location on Mars for on-site analysis as long as they bounce down within their landing ellipse. Their longevity suggests that they may even survive for long enough to serve as landing beacon for later missions.

As for ISRU experiments (Sabatier reaction etc etc) I imagine they would be done from a landed Red Dragon on another, perhaps simultaneous, mission. The MERs would exclusively serve to characterize specific, promising landing locations.

Looking forward to seeing someone try to fit the MERs and associated heatshields within a Falcon Heavy fairing, and perhaps estimate the weight budget.

Offline LM13

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Superficial answer:

(mass deliverable to Mars by FH)/(mass of MER in cruise configuration)


Slightly less superficial: FH payload fairing volume/volume of MER cruise stage (modeled as cylinder of height 1.6 m and diameter 2.65 m). 

An MER, at TMI, massed 1.063 tonnes.  Round up to 1.100 tonnes (for any kind of metal frame between the rovers).  FH TMI payload is 16.8 tonnes (expendable?), suggesting 15 MERs. 

Internal payload fairing diameter is 4.6 m (possibly outdated--taken from old user's guide).  This tapers a bit at the nose, but still seems to stay above 2.65 m for at least 8 meters, so you could launch 5 MERs at a time.  I suspect this would be a mostly-reusable FH.

Of course, this seems to be a variant of the "rebuilding the Saturn V" problem--we have the blueprints, but getting the production line back together could be troublesome.  Suppliers may well be out-of-business by now, parts might be out-of-stock. 

Offline Zed_Noir

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Superficial answer:

(mass deliverable to Mars by FH)/(mass of MER in cruise configuration)


Slightly less superficial: FH payload fairing volume/volume of MER cruise stage (modeled as cylinder of height 1.6 m and diameter 2.65 m). 

An MER, at TMI, massed 1.063 tonnes.  Round up to 1.100 tonnes (for any kind of metal frame between the rovers).  FH TMI payload is 16.8 tonnes (expendable?), suggesting 15 MERs. 

Internal payload fairing diameter is 4.6 m (possibly outdated--taken from old user's guide).  This tapers a bit at the nose, but still seems to stay above 2.65 m for at least 8 meters, so you could launch 5 MERs at a time.  I suspect this would be a mostly-reusable FH.

Of course, this seems to be a variant of the "rebuilding the Saturn V" problem--we have the blueprints, but getting the production line back together could be troublesome.  Suppliers may well be out-of-business by now, parts might be out-of-stock.

Not too big a manufacturing hurdle to handle. The CTO of the company that provide the FH have side businesses manufacturing electric car & comsats. So if you can persuade him that building new MER size rovers have merit, than he can conjoured up some mini rovers.  ;D

Offline Oersted

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #10 on: 05/09/2017 09:17 AM »
Superficial answer:

(mass deliverable to Mars by FH)/(mass of MER in cruise configuration)


Slightly less superficial: FH payload fairing volume/volume of MER cruise stage (modeled as cylinder of height 1.6 m and diameter 2.65 m). 

An MER, at TMI, massed 1.063 tonnes.  Round up to 1.100 tonnes (for any kind of metal frame between the rovers).  FH TMI payload is 16.8 tonnes (expendable?), suggesting 15 MERs. 

Internal payload fairing diameter is 4.6 m (possibly outdated--taken from old user's guide).  This tapers a bit at the nose, but still seems to stay above 2.65 m for at least 8 meters, so you could launch 5 MERs at a time.  I suspect this would be a mostly-reusable FH.

Of course, this seems to be a variant of the "rebuilding the Saturn V" problem--we have the blueprints, but getting the production line back together could be troublesome.  Suppliers may well be out-of-business by now, parts might be out-of-stock.

Thanks, LM, for that very informative first assessment. Five, that's pretty good! And with lots of extra mass capacity so it could possibly allow for reuse of at least the side boosters.

I was wondering if there would be room to pack the MERs around a central bus, perhaps three to a side and on two levels, making six in total? That could be useful when deploying. Or they could fly a couple together with a Red Dragon.

I realise it would be quite a huge undertaking, but reconnoitering the Martian surface will IN ANY CASE be a momentous job. Not starting from zero but actually utilizing presently used flight- and surface-operations-hardware could be a useful shortcut, I think.

As for the "rebuilding Saturn V"-issue, well, I don't think it is too bad. JPL is extremely diligent about documenting their work and test procedures. CAD files exist of all hardware. The people are alive and the companies that built the rovers are still here as well, AFAIK.

Offline Kaputnik

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #11 on: 05/10/2017 08:28 AM »
The science community is not asking for this.
They are asking for sample return.

A much more interesting question is: what would a SpaceX led MSR mission look like?
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Offline Oersted

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #12 on: 05/10/2017 08:44 AM »
SpaceX is not focused on Mars to satisfy the science community. They are in it for colonization. Obviously, down the road, Mars colonization will hugely benefit the science community. Specifically there will be huge amounts of sample return.

If MERs were to fly to Mars on a Falcon Heavy they would go with instruments to characterise soil, rock and water.

Do anyone see a better, cheaper and faster way to surface-reconnoiter colony candidate sites?
« Last Edit: 05/10/2017 08:44 AM by Oersted »

Offline Kaputnik

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #13 on: 05/10/2017 10:42 AM »
SpaceX is not focused on Mars to satisfy the science community. They are in it for colonization. Obviously, down the road, Mars colonization will hugely benefit the science community. Specifically there will be huge amounts of sample return.

If MERs were to fly to Mars on a Falcon Heavy they would go with instruments to characterise soil, rock and water.

Do anyone see a better, cheaper and faster way to surface-reconnoiter colony candidate sites?

So are you suggesting that SpaceX contract JPL to build them dozens of MERs? At $400m each at 2003 costs?* I'm not even sure what the legal position would be if part of NASA were asked to provide a commercial service like that.

A precursor to manned colonisation would be better served by a different set of instruments, especially large subsurface drills.


*To be fair, the program was initially costed at $600m for a single rover, so the additional cost per rover is 'only' $200m and of we take out the launch cost it's only about $140m. Plus inflation to 2017 costs.
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Online spacenut

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #14 on: 05/10/2017 01:09 PM »
We have only scratched the surface of Mars.  If SpaceX is going, like someone said, a satellite system needs to be installed to globally cover Mars.  Then there may need to be some communication satellites in orbit around the sun to be able to have continuous access to Mars.  Then we not only need rovers, but we need serious ground radar and drilling robots to see what is under the Martian surface, like how much water?, what minerals and chemicals? 

Offline Jimmy Murdok

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #15 on: 05/10/2017 01:43 PM »
A JPL solution would be very expensive for SpaceX way of doing things, I can see few JPL advisors into a partial time task force team mostly composed by Tesla and SpaceX employees. Similar to Pica knowledge transfer.

How do you get rid of the expensive plutonium heaters in a fully electric design? ???

Offline Kaputnik

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #16 on: 05/10/2017 03:19 PM »
A JPL solution would be very expensive for SpaceX way of doing things, I can see few JPL advisors into a partial time task force team mostly composed by Tesla and SpaceX employees. Similar to Pica knowledge transfer.

How do you get rid of the expensive plutonium heaters in a fully electric design? ???

Buy Li ion cells from Samsung of course.
« Last Edit: 05/10/2017 03:19 PM by Kaputnik »
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Offline whitelancer64

SpaceX is not focused on Mars to satisfy the science community. They are in it for colonization. Obviously, down the road, Mars colonization will hugely benefit the science community. Specifically there will be huge amounts of sample return.

If MERs were to fly to Mars on a Falcon Heavy they would go with instruments to characterise soil, rock and water.

Do anyone see a better, cheaper and faster way to surface-reconnoiter colony candidate sites?

Yes. Build a clean-sheet, customized design for the purpose, rather than make a kludge with obsolete parts and designs.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline Oersted

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #18 on: 05/10/2017 03:49 PM »
How do you get rid of the expensive plutonium heaters in a fully electric design? ???

No plutonium in the MERs. That is Curiosity.

Online guckyfan

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #19 on: 05/10/2017 04:06 PM »
How do you get rid of the expensive plutonium heaters in a fully electric design? ???

No plutonium in the MERs. That is Curiosity.

Unfortunately not true. The MERs don't have RTG, but they do have small devices producing heat to keep them from getting too cold over night.

Offline whitelancer64

How do you get rid of the expensive plutonium heaters in a fully electric design? ???

No plutonium in the MERs. That is Curiosity.

The MER rovers have 8 Radioisotope Heater Units with about 3 grams of Plutonium 238 each.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline Oersted

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #21 on: 05/10/2017 04:30 PM »
SpaceX is not focused on Mars to satisfy the science community. They are in it for colonization. Obviously, down the road, Mars colonization will hugely benefit the science community. Specifically there will be huge amounts of sample return.

If MERs were to fly to Mars on a Falcon Heavy they would go with instruments to characterise soil, rock and water.

Do anyone see a better, cheaper and faster way to surface-reconnoiter colony candidate sites?

Yes. Build a clean-sheet, customized design for the purpose, rather than make a kludge with obsolete parts and designs.

"Clean-sheet" and "customised" certainly sounds better, but not cheaper and certainly not faster.

SpaceX has a huge amount of work on their plate. I think it won't hurt them to outsource some of it, and then why not outsource to the undisputed leaders in the field of Mars exploration, the JPL?

A cooperation with the JPL around MER-based reconnaissance rovers will also be a huge boon for SpaceX as regards knowledge-transfer about Mars.

"We offer the delivery to Mars and together we cooperate on site-selection and the construction of rovers".. - Would JPL turn down such a deal?

Offline Oersted

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #22 on: 05/10/2017 04:34 PM »
How do you get rid of the expensive plutonium heaters in a fully electric design? ???

No plutonium in the MERs. That is Curiosity.

The MER rovers have 8 Radioisotope Heater Units with about 3 grams of Plutonium 238 each.

Ah yes, I stand corrected, I had forgotten about those small heaters.

Offline rakaydos

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #23 on: 05/10/2017 05:16 PM »
Is there anything fundamental keeping a rover from being designed with low temperature stable electronics? It would certiantly complicate testing, launch and transit if it has to be shipped to mars in a refrigerator, but a rover that doesnt need to warm itself up at night might have certian benifits.

Offline Phil Stooke

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #24 on: 05/10/2017 05:23 PM »
The batteries are at least as needy as the electronics when it comes to keeping warm.  Are there now any low temperature batteries which could replace the MER battery design?

Offline whitelancer64

If the temperature were stable, that would be no problem. There are plenty of low-temperature rated parts out there. The issue is thermal variance. It's roughly a 100 degree C swing between day and night temperatures on Mars, that will cause expansion and contraction, leading to broken parts.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
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Offline Dao Angkan

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #26 on: 05/10/2017 05:46 PM »
SpaceX is not focused on Mars to satisfy the science community. They are in it for colonization. Obviously, down the road, Mars colonization will hugely benefit the science community. Specifically there will be huge amounts of sample return.

If MERs were to fly to Mars on a Falcon Heavy they would go with instruments to characterise soil, rock and water.

Do anyone see a better, cheaper and faster way to surface-reconnoiter colony candidate sites?

Yes. Build a clean-sheet, customized design for the purpose, rather than make a kludge with obsolete parts and designs.

"Clean-sheet" and "customised" certainly sounds better, but not cheaper and certainly not faster.

SpaceX has a huge amount of work on their plate. I think it won't hurt them to outsource some of it, and then why not outsource to the undisputed leaders in the field of Mars exploration, the JPL?

A cooperation with the JPL around MER-based reconnaissance rovers will also be a huge boon for SpaceX as regards knowledge-transfer about Mars.

"We offer the delivery to Mars and together we cooperate on site-selection and the construction of rovers".. - Would JPL turn down such a deal?

Or cooperate with ESA to make a duplicate ExoMars rover bus. They'd still run into the RHU issue though, even more so as Russia is supplying it. A 2-metre drill might be handy for regolith ice collection if they want to perform some ISRU experiments.
« Last Edit: 05/10/2017 05:49 PM by Dao Angkan »

Offline Kaputnik

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #27 on: 05/10/2017 07:29 PM »
I'd imagine an in-house SpaceX Mars rover would throw mass at the problem, and just have larger solar arrays with electric heaters
They would probably also use a Dragon as the starting point for the landing vehicle, rather than try to duplicate NASA's design, which relies on some very specialsed technology.

(Note- NASA developed a Mars EDL architecture in the 70s for Viking and has reused it every time since then. Same cone/sphere heatshield shape, same disk-gap-band supersonic parachute. Only the terminal landing sequence has been altered, to suit each mission).
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Offline whitelancer64

I'd imagine an in-house SpaceX Mars rover would throw mass at the problem, and just have larger solar arrays with electric heaters
They would probably also use a Dragon as the starting point for the landing vehicle, rather than try to duplicate NASA's design, which relies on some very specialsed technology.

(Note- NASA developed a Mars EDL architecture in the 70s for Viking and has reused it every time since then. Same cone/sphere heatshield shape, same disk-gap-band supersonic parachute. Only the terminal landing sequence has been altered, to suit each mission).

Not so, the EDL hardware designs were similar, but not the same.

The MER heat shield was a different size and the backshell had a different geometry than the Viking landers, for example. Also the parachutes for the MER program were smaller and had to be extensively redesigned - early testing had squidding and tearing problems, with one parachute shredded completely.

Curiosity was heavier than the Viking landers and so had a larger parachute, backshell, and heat shield (which was made of PICA).
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline synchrotron

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #29 on: 05/10/2017 08:13 PM »
I'd imagine an in-house SpaceX Mars rover would throw mass at the problem, and just have larger solar arrays with electric heaters
They would probably also use a Dragon as the starting point for the landing vehicle, rather than try to duplicate NASA's design, which relies on some very specialsed technology.

(Note- NASA developed a Mars EDL architecture in the 70s for Viking and has reused it every time since then. Same cone/sphere heatshield shape, same disk-gap-band supersonic parachute. Only the terminal landing sequence has been altered, to suit each mission).

The disk-gap-band parachutes have undergone considerable redesign for the later missions. While the Viking data was and is invaluable, the dynamics of the EDL can vary considerably depending on the mission. In general, most re-use in exploration spaceflight is know-how rather than designs.

Offline Kaputnik

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #30 on: 05/10/2017 08:15 PM »
I'd imagine an in-house SpaceX Mars rover would throw mass at the problem, and just have larger solar arrays with electric heaters
They would probably also use a Dragon as the starting point for the landing vehicle, rather than try to duplicate NASA's design, which relies on some very specialsed technology.

(Note- NASA developed a Mars EDL architecture in the 70s for Viking and has reused it every time since then. Same cone/sphere heatshield shape, same disk-gap-band supersonic parachute. Only the terminal landing sequence has been altered, to suit each mission).

Not so, the EDL hardware designs were similar, but not the same.

The MER heat shield was a different size and the backshell had a different geometry than the Viking landers, for example. Also the parachutes for the MER program were smaller and had to be extensively redesigned - early testing had squidding and tearing problems, with one parachute shredded completely.

Curiosity was heavier than the Viking landers and so had a larger parachute, backshell, and heat shield (which was made of PICA).

Perhaps I overstated the similarity. They are pretty much the same idea, though, just at different scale. And Curiosity maxes out the parachute technology, still on decades old upper atmoshere testing done in support of Viking. IIRC some versions used a ballistic entry and others used offset CG lifting entry.

The key point is that this can really be considered a single design, just at different scales, when compared to Dragon, which is a completely different approach
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Offline whitelancer64

I'd imagine an in-house SpaceX Mars rover would throw mass at the problem, and just have larger solar arrays with electric heaters
They would probably also use a Dragon as the starting point for the landing vehicle, rather than try to duplicate NASA's design, which relies on some very specialsed technology.

(Note- NASA developed a Mars EDL architecture in the 70s for Viking and has reused it every time since then. Same cone/sphere heatshield shape, same disk-gap-band supersonic parachute. Only the terminal landing sequence has been altered, to suit each mission).

Not so, the EDL hardware designs were similar, but not the same.

The MER heat shield was a different size and the backshell had a different geometry than the Viking landers, for example. Also the parachutes for the MER program were smaller and had to be extensively redesigned - early testing had squidding and tearing problems, with one parachute shredded completely.

Curiosity was heavier than the Viking landers and so had a larger parachute, backshell, and heat shield (which was made of PICA).

Perhaps I overstated the similarity. They are pretty much the same idea, though, just at different scale. And Curiosity maxes out the parachute technology, still on decades old upper atmoshere testing done in support of Viking. IIRC some versions used a ballistic entry and others used offset CG lifting entry.

The key point is that this can really be considered a single design, just at different scales, when compared to Dragon, which is a completely different approach

A similar EDL method would be a better way to put it.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline Oersted

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #32 on: 05/11/2017 07:57 AM »
I'd imagine an in-house SpaceX Mars rover would throw mass at the problem, and just have larger solar arrays with electric heaters
They would probably also use a Dragon as the starting point for the landing vehicle, rather than try to duplicate NASA's design, which relies on some very specialsed technology.

"landing vehicle" you say, but mobility will be crucial to reconnoiter a possible colony location. Building a rover from scratch and then modifying Red Dragon to deploy it sounds to me like a huge job, compared to the approach I am proposing.
« Last Edit: 05/11/2017 07:57 AM by Oersted »

Offline philw1776

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #33 on: 05/13/2017 07:30 PM »
I ran engineering, developed new products and put them in production and supported them.  One major problem with old designs in production is the obsolescence of electronics parts which evolve rapidly.  In telecom we contractually signed up to provide more of a given product 10 years beyond initial purchase. Commercially we forecast a lifetime build # of units and then did a final stock buy of the many parts that our vendors were dropping during this 10 year period. 
JPL's design is ancient.  Worse yet they used proven parts that were old at the time.  Again worse they used many specialized low volume parts not kept in production for anyone else.  Unless (and the probability here approaches zero) they spent $ to create a stockroom able to build N future rovers, the parts are long gone.  The original manufacturers no longer have the capability to make any more.  Semiconductors have evolved so many generations since that the tools and the tools to make the tools may be gone.  Test fixtures are gone, discarded long ago.  Solutions like this proposed reflect zero experience designing and maintaining real electronics products.

The isotope heaters produce another complex series of problems.  Many political as well as expensive.
“When it looks more like an alien dreadnought, that’s when you know you’ve won.”

Offline bunker9603

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #34 on: 05/13/2017 08:31 PM »
Quote
Not too big a manufacturing hurdle to handle. The CTO of the company that provide the FH have side businesses manufacturing electric car & comsats. So if you can persuade him that building new MER size rovers have merit, than he can conjoured up some mini rovers.
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I would like to see what engineers from Tesla, Solar City, SpaceX and JPL would come up with if they designed a new rover.

Also would it be possible to use drones on Mars?
« Last Edit: 05/13/2017 08:32 PM by bunker9603 »

Online guckyfan

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Re: How many Opportunity Rovers could Falcon Heavy fly to Mars?
« Reply #35 on: 05/13/2017 09:02 PM »
I will try another argument. Assume they find a forgotten store of 20 Opportunity rovers and they are all operational. SpaceX can have them for free. Would they accept them and use them? No way, they are just too far from what SpaceX needs.

Maybe they could disassemble them and use those nuclear heat sources.

Tags: drones?