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#251 2019-06-01 11:38:04

GW Johnson
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Metal matrix composites have the potential to be as strong and as energy-absorbing as straight wrought metals.  Dispersing aluminum oxide particles in cast aluminum is not the way to achieve that,  although a strength improvement over wrought aluminum is likely.  I doubt the elongation will be there with particle reinforcement instead of fiber reinforcement.  Woven fabric reinforcement is the approach that works best.  That would be aluminosilicate fire curtain fabric wetted with molten aluminum,  but I know of no products on the market like that to choose from.

Assuming particle-reinforced aluminum products cost no more than 316 stainless per what Kbd512 said just above,  then you are trading impact resistance for weight between the two.  The aluminum composite may be stronger than wrought aluminum,  but I very seriously doubt it has more impact resistance than a 300-series stainless.  Those stretch a really long way before they fail.  The integral under the stress-strain curve is huge,  especially in the annealed state,  which is EXACTLY what you want for impact resistance.

Since impact damage accumulates over time,  time is the deciding variable.  If you require only a short mission,  you can save a handful of pounds,  and use the aluminum composite tires.  They will hold up a little better than the wrought aluminum tires,  and be no heavier. 

But if you want a long mission,  you add the few pounds and use the stainless.  Then you get years out of your rover over any terrain, instead of just months even with route restrictions to avoid sharp rocks.

You get EXACTLY what you design for,  as well as what you pay for.  It would appear that nobody with any authority asked the "how long" question designing Curiosity.

That's a fundamental part of engineering design.  There's just more to it than just the bottom line of the weight statement,  or the $bottom $line of the item price tag. Inherent with constrained optimization. 

I used to see more folks in authority allowing for that,  but not so much anymore. Sad.

GW

Last edited by GW Johnson (2019-06-01 11:40:50)


GW Johnson
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#252 2019-06-01 13:05:50

SpaceNut
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

I do not think longevity was ever a question as when we look to spirit and opportunity these were for a 90 day mission that lasted way longer as they stayed functional. Most likely that was how curiousity was designed as well with thoughts that it might survive longer but not planning for it with design....
What I am not seeing is the lessons learned entering in with the next ones that are built for rover use.

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#253 2019-06-02 11:15:26

GW Johnson
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Spirit and Opportunity were designed with solar electric as power source,  with an expected lifetime of months to maybe a year or so.  They were also rather small, lowering the impact loads on wheels of any practical design. 

Curiosity is nuclear-powered,  with an expected lifetime of several years.  It is very much larger and heavier,  which greatly increases the impact loads on any conceivable wheel design.  Like the small rovers,  it also has 6 wheels. 

They got a lot of things right with Curiosity's design,  but they obviously screwed up the aluminum wheel design.  On the face of it,  I suspect that was just a design question they forgot to ask themselves.  And it would be someone outside their spacecraft design realm that would have the "right" answer. 

Having developed a piece of farm equipment that is a drag tool used on rocky land,  I know by hard knocks' experience that when you drag steel through rocks,  the rocks eventually win.  You make it big and heavy,  and the "eventually" part gets long enough to be practical.  Aluminum is right out.  So is titanium.  Neither has anything near the "engineering toughness" of a steel,  especially 300-series Austenitic stainless. Especially in the cold of Mars.

I doubt there is anyone at all at JPL with that kind of hard-knocks experience dealing with moving through and over rocks.  I was an aerospace engineer for 20 years in the industry,  and I didn't get that knowledge from anything I ever did in that career!  I got it on my home farmstead in rural Texas,  doing pasture improvement.  That's not aerospace,  it's agriculture.  But it is engineering.

Point is,  sometimes your best solutions to problems come from unlikely places you would never have imagined.  That's just life.

GW

Last edited by GW Johnson (2019-06-02 11:18:46)


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#254 2019-06-02 11:37:47

Void
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

That is a very good thought.

I have some speculation on such probes, and Starship.  I will try to color inside the lines of reality though and hope to not "Put you out".

I have read some chatter, that the two actual Starships that are being built are intended to do sub-orbital testing, and then if possible an orbital launch.  It gets fuzzier after that.  They may not even try to bring them back.  This could explain why they look like sheets of metal pasted together with welding.  If they do not bring them back, then I wonder if they have any utility in orbit after that.  But that gets far off the track of what I want to actually talk about.  If they do that though then they can save solving the heat shield problem for later editions of the Starship.

If they do what is said in the previous paragraph, I guess it means that they don't mind expending the effort, as it will give them important test information, to base subsequent editions of the device on.  So test information may be worth the expenditure.

So, I have thought of several missions to Mars that might supply test information that may be of similar value, and may even justify sacrificing a Starship for.

Spirit, Opportunity, and Curiosity may be devices that can be replicated with some upgrades such as the wheels you have spoken of.  But for the most part, you would not have to re-invent the wheel.

So, I would suggest that a multitude of such probes could be conveyed to Mars by various methods also using a Starship.  The reason to do this would be to get "Ground Truth" from many locations on Mars.  This could be preferable to having humans scout out the planet from a Mars base.  I think humans at the Mars base will have their hands full just trying to make the base work.  The Starship in this case may not have a heat shield since it may be discarded into a solar orbit.

So, here are a few ideas for it:

1) Fully expendable Starship.  Starship does not ever land anywhere.  But it carries a bunch of these probes to Mars and releases them.  They each have to make their way through the atmosphere to the ground.  In this case, it may be possible to try to sterilize the probes.

2) Landing ship.  It would release the probes prior to landing, and they would be on their own, but it would land itself.  Perhaps with little or no cargo.  It's use on the surface after that might be extra living space at the base to be built.  It may not make sense to try to sterilize the probes, since the landing Starship would not be sterilized anyway.

*In #2, I can see the costs going down quite a lot.

3) A starship deploy of probes to Mars, and a return to Earth.  Heat shield desired.  Here it is not clear to me if enough propellants can be available.  It would have to get the probes offloaded to go to Mars.  Perhaps those probes would have some ion thrusters such as Starlink devices do, to trim their paths to what is wanted.  The Starship may after disposing of the probes, use a gravity swing around Mars, but would also likely need sufficient propellants to further put it's path to Earth.

As I have said, the purpose of these notions would be to allow people on Earth to explore Mars further, possibly locating resources, but for sure better defining what Mars is like.  Knowing more about Mars will make any effort to settle people on Mars would enhance the possibility of success in the effort.

And I guess to pull this off with so many probes, it would be necessary to upgrade communication abilities Earth<>Mars.

Done

Last edited by Void (2019-06-02 12:00:04)


Done.

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#255 2019-08-05 21:45:14

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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

This would explain the images in some parts of mars
An ancient Mars crater likely spawned a devastating mega-tsunami

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#256 2019-08-06 19:01:46

SpaceNut
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Happy Birthday its been seven years.... time for a selfy
capture-26.jpg

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#257 2019-08-11 21:12:56

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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Investigating past as well as present life will come in the viewing of mars clay... Investigating

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#258 2019-10-07 21:17:03

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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

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#259 2020-03-09 20:46:20

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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

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#260 2020-03-10 11:29:18

GW Johnson
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Balancing the available evidence against the need for "extraordinary evidence for extraordinary claims" is tricky at best. 

There seem to be both life and non-life explanations for what the instruments on Viking saw. 

There seem to be both life and non-life explanations for the purported microbe fossils seen in the Allan Hills 84001 meteorite from Mars. 

There may be both life and non-life explanations for the thiophenes seen by Curiosity. 

And there's likely more such examples.  I dunno,  I haven't kept up with all of those. 

But there's a trend here:  multiple examples over many years of things that may indicate at least past life on Mars.  Couple that with the current thinking that life forms fairly easily if liquid water and sunlight are present.  Such was true for the first billion years or so on Mars,  as best we understand.

My best guess (and guess it is) is that eventually we will find underground living remnant microbe populations on Mars,  and fossil traces of widespread earlier surface microbe life on Mars.  It will take years of people searching on Mars to uncover all this.  But I do believe that eventually we will. 

GW

Last edited by GW Johnson (2020-03-10 11:31:16)


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#261 2020-03-11 04:52:52

elderflower
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

I believe that it is quite likely also, GW.
If chiral molecules are found with a very large preponderance of one hand over the other I would think this would be a clear indication of life. It won't say whether it is past or present, though.
I also think it quite likely that life on both planets will show a common origin, perhaps from a third place or perhaps from swapping rocks over the ages.

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#262 2020-03-11 12:34:53

GW Johnson
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

What the two discredited NASA scientists found and reported inside the meteorite was small (microscopic) fossils of what they said was microbes.  In Earthly rocks at a larger size,  the same sort of traces have long been accepted as evidence of microbial life. 

I think the discrediting they received was undeserved.  What they uncovered should have been followed up.  It was not. 

This meteorite was a rock formed on Mars when it was only about a billion years old,  back when it had an ocean and an Earth-like climate.  It got blown off by an asteroid impact much later in Martian history.  All that has been verified. 

But nobody else wanted to accept the traces as microbe fossils.

GW


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#263 2020-07-07 07:53:20

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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Curiosity Mars Rover's Summer Road Trip NEWS  | July 6, 2020

BB16qK0z.img?h=340&w=640&m=6&q=60&o=f&l=f

Curiosity Mars Rover's Summer Road Trip Has Begun

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#264 2021-03-11 08:04:08

Tmcom
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

GW Johnson wrote:

Balancing the available evidence against the need for "extraordinary evidence for extraordinary claims" is tricky at best. 

There seem to be both life and non-life explanations for what the instruments on Viking saw. 

There seem to be both life and non-life explanations for the purported microbe fossils seen in the Allan Hills 84001 meteorite from Mars. 

There may be both life and non-life explanations for the thiophenes seen by Curiosity. 

And there's likely more such examples.  I dunno,  I haven't kept up with all of those. 

But there's a trend here:  multiple examples over many years of things that may indicate at least past life on Mars.  Couple that with the current thinking that life forms fairly easily if liquid water and sunlight are present.  Such was true for the first billion years or so on Mars,  as best we understand.

My best guess (and guess it is) is that eventually we will find underground living remnant microbe populations on Mars,  and fossil traces of widespread earlier surface microbe life on Mars.  It will take years of people searching on Mars to uncover all this.  But I do believe that eventually we will. 

GW

https://www.youtube.com/watch?v=bOgZOhlNCiM&t=1s

Nope, NASA want to maintain a propaganda regime, and these billion dollar rovers fit their narrative nicely.

I have found pure water droplets on the second last rover, dispelling the air pressure can boil away water myth and strongly hinting at rain.

Or demonstrating that Mars is a lot more earthlike than what they will admit, which makes no sense, on the surface, unless someone or something is living there, and has energy systems, (that we keep burying) that threatens oil profits.

This all sounds pretty far fetched, but Mars is in the habitable zone, and Hubble as well as anyone pointing a telescope at Mars, Always sees a blue atmosphere.

But anyway NASA cannot keep a lid on this forever, or someone who isn't biased will land something there and show the world eventually.

This will all come up soon enough, and scare the hell out of a lot of people who have made a career out of ostriches doing the obvious.

The images in the video are from the rovers raw images, Sol 600+, mast cam.

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#265 2021-03-11 09:38:23

Calliban
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Tmcom, would you care to place a wager?  I will bet you a tenner that median air pressure on the Martian surface does not exceed 1KPa.  If the world discovers otherwise by 2040, say, I will pay up.  If not, you pay up.  The Chinese are in orbit around Mars right now and must be aware of atmospheric density to be able to design an aerobraking system.  Are they also in on the con?

Last edited by Calliban (2021-03-11 09:39:03)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#266 2021-03-11 19:40:20

Tmcom
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Calliban wrote:

Tmcom, would you care to place a wager?  I will bet you a tenner that median air pressure on the Martian surface does not exceed 1KPa.  If the world discovers otherwise by 2040, say, I will pay up.  If not, you pay up.  The Chinese are in orbit around Mars right now and must be aware of atmospheric density to be able to design an aerobraking system.  Are they also in on the con?

China, Russia and the US, have all made a pact to stay Mum on the subject, so no you will be paying.

I suggest that you watch the video, pure water droplets on the rover, which can only come from rain, and wet sand at the same time to back it up.

The proof is in front of your face, and if NASA wasn't fibbing then why didn't they release this news to the world, answer: they want to release a trickle to the small percentage of the worlds population that can still think rationally, so they can manage the majority that will go ape-shit when this is all released, (well, before 2040).

I suspect that NASA will own up in 12 years time, have your PayPal email ready.

smile

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#267 2021-03-11 20:24:39

louis
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

I do agree that NASA obfuscate. There is no logical reason for using the orange filter and the grid that both obscure detail in photos. It also seems odd that in 50 years NASA have really failed to improve picture quality to any great degree.

On the other hand I don't think they are lying about atmospheric pressures. There is no reason to do that.

There's something going on with NASA - they've spent 50 years denying there's any life on Mars and now, with Perseverance, they seem to have set everything up to announce there is life or has been in the past. Very odd! But I think it might be because NASA have now been captured by the international "planetary protection" mafia.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#268 2021-03-11 21:16:48

SpaceNut
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

The answer to the air pressure is in the
jpegPIA24336.width-640.jpg

This it from high above the surface as imaged from High Resolution Imaging Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter (MRO).
This one is not the parachute of the landings but it shows how the parachute inflates to be able cause drag....

8671_PIA23890-16.gif

This page has a video of it opening plus shows the heat shield or back shell dropping

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#269 2021-03-12 03:15:06

Tmcom
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

louis wrote:

I do agree that NASA obfuscate. There is no logical reason for using the orange filter and the grid that both obscure detail in photos. It also seems odd that in 50 years NASA have really failed to improve picture quality to any great degree.

On the other hand I don't think they are lying about atmospheric pressures. There is no reason to do that.

There's something going on with NASA - they've spent 50 years denying there's any life on Mars and now, with Perseverance, they seem to have set everything up to announce there is life or has been in the past. Very odd! But I think it might be because NASA have now been captured by the international "planetary protection" mafia.

No Louis, they are, air pressures like earth mean a higher possibility of life, as does the -173 at night one lie, (they moved the decimal point on all of their data, or it is lucky to get down to minus 2 at night not minus 200).

They botch up Viking, then after Carl Sagan went on a monitor rampage, it has been orange screens ever since.

They know that after 50 years of knocking anyone who see's anything weird, as nuts then releases satanic aliens at area 51, propaganda to scare everyone on youtube, (watch PAUL, that movie takes the p...s out of all of that crap) they will have a hard time controlling mass paragrim shifting individuals in shock smashing in any tv store available.

And NASA do release HD images on rare occasions, (check out the last image on the Mars, stealth mission thread).

SpaceNut wrote:

The answer to the air pressure is in the
https://d2pn8kiwq2w21t.cloudfront.net/i … th-640.jpg

This it from high above the surface as imaged from High Resolution Imaging Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter (MRO).
This one is not the parachute of the landings but it shows how the parachute inflates to be able cause drag....

https://mars.nasa.gov/system/news_items … 890-16.gif

This page has a video of it opening plus shows the heat shield or back shell dropping

Agreed if it was a near vacuum, then it wouldn't be opening like it did, (the moon is a near vacuum, and as Buzz showed with his feather experiment it would have been useless).

smile

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#270 2021-03-12 06:41:43

Calliban
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Look at old photos of the original Viking landings and you will find one with frost, taken early in the morning.
https://solarviews.com/cap/mars/frost.htm

As temperatures declined over night, water vapour that had evaporated from the regolith during the day, frosted out on the surface. As temperatures increased throughout the day, it sublimed. Could it melt giving rise to water droplets before it evaporated? Actually, yes. The atmospheric pressure at Curiosity's landing site was found to fluctuate between 690 and 790Pa. The vapour pressure of water at 0°C is 611Pa. If the surface of Mars rocks is contaminated with soluble salts like perchlorate, then frost could melt at temperatures as low as -40°C.

So yes, it is possible for water droplets to form on the surface of Mars. If there is sufficient salt content and the ice melts far beneath the usual freezing point of water, the vapour pressure of the brine (which declines as a function of temperature) could be substantially lower than the local atmospheric pressure on Mars. So it is possible for water droplets to hang around, without imminently freezing due to evapouration.

It doesn't take an elaborate conspiracy theory to explain this. It is plausible under established conditions. It is in fact entirely possible that parts of the Martian surface contain enough liquid water to get muddy at certain times of the year. But that mud would form from saturated brine rather from pure water. It is unlikely to contain microbes, though we won't know for sure until a visiting science team examine the mud under a microscope.

The global average atmospheric pressure on Mars is 610Pa. That is just 1Pa beneath the vapour pressure of pure water at normal freezing point. That is unlikely to be a coincidence. Carbon dioxide is highly soluble in liquid water, forming carbonic acid. Any CO2 dissolving into liquid water on Mars would react with bases in the regolith to form stable carbonates. The low pressure of the Martian atmosphere is likely the result of a long established equilibrium between the atmosphere and frozen water ice.


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#271 2021-03-12 06:55:37

Calliban
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Tmcom wrote:
louis wrote:

I do agree that NASA obfuscate. There is no logical reason for using the orange filter and the grid that both obscure detail in photos. It also seems odd that in 50 years NASA have really failed to improve picture quality to any great degree.

On the other hand I don't think they are lying about atmospheric pressures. There is no reason to do that.

There's something going on with NASA - they've spent 50 years denying there's any life on Mars and now, with Perseverance, they seem to have set everything up to announce there is life or has been in the past. Very odd! But I think it might be because NASA have now been captured by the international "planetary protection" mafia.

No Louis, they are, air pressures like earth mean a higher possibility of life, as does the -173 at night one lie, (they moved the decimal point on all of their data, or it is lucky to get down to minus 2 at night not minus 200).

They botch up Viking, then after Carl Sagan went on a monitor rampage, it has been orange screens ever since.

They know that after 50 years of knocking anyone who see's anything weird, as nuts then releases satanic aliens at area 51, propaganda to scare everyone on youtube, (watch PAUL, that movie takes the p...s out of all of that crap) they will have a hard time controlling mass paragrim shifting individuals in shock smashing in any tv store available.

And NASA do release HD images on rare occasions, (check out the last image on the Mars, stealth mission thread).

SpaceNut wrote:

The answer to the air pressure is in the
https://d2pn8kiwq2w21t.cloudfront.net/i … th-640.jpg

This it from high above the surface as imaged from High Resolution Imaging Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter (MRO).
This one is not the parachute of the landings but it shows how the parachute inflates to be able cause drag....

https://mars.nasa.gov/system/news_items … 890-16.gif

This page has a video of it opening plus shows the heat shield or back shell dropping

Agreed if it was a near vacuum, then it wouldn't be opening like it did, (the moon is a near vacuum, and as Buzz showed with his feather experiment it would have been useless).

smile

It would open in exactly the way that you see it opening.  Remember, the parachute is deployed at a descent speed of about 1000mph (450m/s).  At this speed and a local atmospheric density of about 6 grams per cubic metre (at a height of 10km, say), the dynamic pressure on the parachute would be 1.2KPa or 120 kg-force per square metre, assuming a drag coefficient of one.  That is equivalent to the weight of a man (in Earth gravity) acting on every square metre of the chute.
Easily enough to open a thin fabric parachute.  In fact, it would be enough to tare the chute into shreds if it weren't made from such high strength polymers.

F = Cd x A x Rho x V^2

Perhaps it would be wise to do a little basic research before mouthing off with unsubstantiated conspiracy theories?  Just a thought :-)

Last edited by Calliban (2021-03-12 06:59:02)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#272 2021-03-12 19:45:18

Tmcom
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

Calliban wrote:

Look at old photos of the original Viking landings and you will find one with frost, taken early in the morning.
https://solarviews.com/cap/mars/frost.htm

As temperatures declined over night, water vapour that had evaporated from the regolith during the day, frosted out on the surface. As temperatures increased throughout the day, it sublimed. Could it melt giving rise to water droplets before it evaporated? Actually, yes. The atmospheric pressure at Curiosity's landing site was found to fluctuate between 690 and 790Pa. The vapour pressure of water at 0°C is 611Pa. If the surface of Mars rocks is contaminated with soluble salts like perchlorate, then frost could melt at temperatures as low as -40°C.

So yes, it is possible for water droplets to form on the surface of Mars. If there is sufficient salt content and the ice melts far beneath the usual freezing point of water, the vapour pressure of the brine (which declines as a function of temperature) could be substantially lower than the local atmospheric pressure on Mars. So it is possible for water droplets to hang around, without imminently freezing due to evapouration.

It doesn't take an elaborate conspiracy theory to explain this. It is plausible under established conditions. It is in fact entirely possible that parts of the Martian surface contain enough liquid water to get muddy at certain times of the year. But that mud would form from saturated brine rather from pure water. It is unlikely to contain microbes, though we won't know for sure until a visiting science team examine the mud under a microscope.

The global average atmospheric pressure on Mars is 610Pa. That is just 1Pa beneath the vapour pressure of pure water at normal freezing point. That is unlikely to be a coincidence. Carbon dioxide is highly soluble in liquid water, forming carbonic acid. Any CO2 dissolving into liquid water on Mars would react with bases in the regolith to form stable carbonates. The low pressure of the Martian atmosphere is likely the result of a long established equilibrium between the atmosphere and frozen water ice.

Except that my video, has water droplets on the rover itself, and no frost before hand.

As l said hard evidence of rain!

Adding all of the other evidence that Mars is not a dead rock!

Ice crystals in those supposed pressures will boil away when they melt, they won't melt first then hold them melt on command.

Yeah, unsubstantiated propaganda!

smile

Last edited by Tmcom (2021-03-12 19:55:51)

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#273 2021-03-13 10:30:45

SpaceNut
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

That occurs when its warm and then suddenly gets colder as it would happen from going from day towards night as the vapor would condense and fall...

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#274 2021-03-13 20:06:51

Tmcom
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

SpaceNut wrote:

That occurs when its warm and then suddenly gets colder as it would happen from going from day towards night as the vapor would condense and fall...

Agreed, but l didn't spot any indications of frost before hand, and going by the biggest drop l saw, it pooled under the rovers wires and remained there until someone at JPL moved the rover.

This was most likely after the Martian sun, evaporated most of the raindrops away, (although l found the occasional one or more).

PS Good to hear from you Spacenut, check out my music thread when you can, hit the jackpot recently.

smile

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#275 2021-03-31 18:24:21

SpaceNut
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Re: Official MSL / Curiosity Rover Thread | Aug 5, 2012 10:31 p.m. PT

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