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Dust storm on Mars is threatening the Opportunity rover.


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39 minutes ago, Kerbart said:

The cynic in me believes that this is the true reason these robots last so much longer than planned. Not because of their exceptional build quality (don’t get me wrong, it is exceptional), but because a rover with an expected life span of, say, 5 years, would burn a gigantic hole in the budget.

so the “official” mission duration is 6 months and now the money for the remaining 4.5 years comes from some other “unexpected mission extensions” budget which allows the official budget to remain passable.

I don’t have proof but I do have suspicions.

 

Could be. Looks like keeping the lights on cost over 15 M$/year for the project. That's a small price to pay for additional data compared to sending a new rover (Oppy itself cost something north of 600 M$ to build and get to Mars).

Still, having a sort of programmatic inertia has some value to the employees.

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13 minutes ago, Gargamel said:

My one fear is that it'll wake up and nobody will be there to talk to it, and it will be all alone.  

It has no ability to feel anything.

Besides, if it tries to phone home, MRO or something might well get the signal, anyway.It's my understanding the coming super cold will finish it off, anyway, it needed power to keep the electronics warm.

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21 minutes ago, Cassel said:

What caused this dust storm?

Sunshine :-)

A dust storm develops when winds are strong enough to vibrate dust particles out of the ground and keep them in suspension. Winds develop through pressure differences over large areas. Pressure differences are the result of temperature differences, which are the result of different heating of the ground by the sun. Type of ground, reflectivity, heat buffering, topography, etc. play a role. Coriolis force and pressure difference determine how strong the winds will be, depending on height, topography, ....

That's in in short. For a given case of a planet wide dust storm on Mars i am not sure if the exact chain of actions, like what must heat up how much and how high must pressure differences be in order to generate which levels of winds and suspend which particle sizes, are known in detail.

Edited by Green Baron
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36 minutes ago, Green Baron said:

Sunshine :-)

A dust storm develops when winds are strong enough to vibrate dust particles out of the ground and keep them in suspension. Winds develop through pressure differences over large areas. Pressure differences are the result of temperature differences, which are the result of different heating of the ground by the sun. Type of ground, reflectivity, heat buffering, topography, etc. play a role. Coriolis force and pressure difference determine how strong the winds will be, depending on height, topography, ....

That's in in short. For a given case of a planet wide dust storm on Mars i am not sure if the exact chain of actions, like what must heat up how much and how high must pressure differences be in order to generate which levels of winds and suspend which particle sizes, are known in detail.

Are you AI or something? Because you write like one.

What about asteroids like this one with strange Hawaii name? Could hit of fast object could cause it?

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18 minutes ago, Cassel said:

Are you AI or something? Because you write like one.

"Your request could not be processed. Please rephrase request." :-)

Quote


What about asteroids like this one with strange Hawaii name? Could hit of fast object could cause it?

Nope. Dust storms on Mars are supraregional events, may even grow planet wide. The are the result of different ground heating, and thus atmospheric temperature and so pressure differences, not caused by atmospheric blasts from impacts.

Concrete simple example, by no means complete or accurate, just to show the principle: let's assume a relatively dark coloured, deep lying basin and the sun shining directly on it (90°).It will heat up faster and more than more lighter areas surrounding it, where the sun hits at an angle. That will cause the overlying air in the basin to heat, start to rise, and then rotate due to coriolis. A deep pressure area L is born. Somewhere in the surrounding, the air will sink to equalize pressure difference, and rotate in the opposite direction. A high pressure area H is born. In between them air will flow rectangular to the centers of L and H, the wind strength will be corresponding to the density of the isobars (pressure difference/distance).

At ground, where the airflow is slowed by topography, pressure difference will slowly equalize and at some time wind will go down until a stable state is reached again. The other day, things may start again. But i must admit, i do know little about the exact conditions on Mars.

Edited by Green Baron
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14 hours ago, Green Baron said:

Sunshine :-)

A dust storm develops when winds are strong enough to vibrate dust particles out of the ground and keep them in suspension. Winds develop through pressure differences over large areas. Pressure differences are the result of temperature differences, which are the result of different heating of the ground by the sun. Type of ground, reflectivity, heat buffering, topography, etc. play a role. Coriolis force and pressure difference determine how strong the winds will be, depending on height, topography, ....

That's in in short. For a given case of a planet wide dust storm on Mars i am not sure if the exact chain of actions, like what must heat up how much and how high must pressure differences be in order to generate which levels of winds and suspend which particle sizes, are known in detail.

So what keeps it alive also kills it...

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14 hours ago, Green Baron said:

"Your request could not be processed. Please rephrase request." :-)

Nope. Dust storms on Mars are supraregional events, may even grow planet wide. The are the result of different ground heating, and thus atmospheric temperature and so pressure differences, not caused by atmospheric blasts from impacts.

Concrete simple example, by no means complete or accurate, just to show the principle: let's assume a relatively dark coloured, deep lying basin and the sun shining directly on it (90°).It will heat up faster and more than more lighter areas surrounding it, where the sun hits at an angle. That will cause the overlying air in the basin to heat, start to rise, and then rotate due to coriolis. A deep pressure area L is born. Somewhere in the surrounding, the air will sink to equalize pressure difference, and rotate in the opposite direction. A high pressure area H is born. In between them air will flow rectangular to the centers of L and H, the wind strength will be corresponding to the density of the isobars (pressure difference/distance).

At ground, where the airflow is slowed by topography, pressure difference will slowly equalize and at some time wind will go down until a stable state is reached again. The other day, things may start again. But i must admit, i do know little about the exact conditions on Mars.

Then making any Mars mission we should look for other power source than solar panels, because they are useless.

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Don't troll me. A mobile device like a rover may be better off with the one or the other, depending on the use case, circumstances, degree of mobility, power requirement. It can be a combination of solar or nuclear, or solely the one or the other. We have been through pros and cons and all that.

This solar driven rover has lasted 14 years and weathered out several dust storms before.

Edited by Green Baron
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3 hours ago, Green Baron said:

This has all been discussed in length, width & height. tl,dr: they are extremely effective.

So why rover is dead? :-)

In my opinion, it can not be called an extremely effective technology that is so sensitive to weather conditions.

Edited by Cassel
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It is not more sensitive to failure, probably less, than other tech. It was just old. The last sandstorm may just have given the aging hardware the last punch.

Efficiency is the measurement of achieving a goal with the least effort. The rover has lasted 55 times as long as planned and successfully weathered through several sandstorms before. I call that, and its achievements during its lifetime, extremely effective and efficient :-)

Edited by Green Baron
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Yeah, while RTGs are better, Opportunity did just fine with solar. It's also important to note that the power production of RTGs over time decreases at a known rate, so while RTGs can survive a dust storm on Sol 1, and still complete the rover mission, they have a fixed time of operation.

NASA RTGs I think are at ~75% power at 15 years. This is pretty good, but unless they also have batteries, there might be an issue if certain functions require more power than ends up available. I simply don't know the answer to this, but it seems plausible that there might be a certain overhead to run systems (say 10% of RTG output), and then if certain maneuvers use more power (climbing a steel slope, for example) then the rover might have to pick an alternate route, lacking the power to maintain overhead, AND drive wheels at max power.

Again, I have no idea in reality, but it's interesting to remember that even RTGs have limitations.

Edited by tater
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1 hour ago, Cassel said:

So why rover is dead? :-)

In my opinion, it can not be called an extremely effective technology that is so sensitive to weather conditions.

The rover is dead because it hasn't been to a mechanic in 15 years. How long would 
YOUR car last without maintinance?

Edited by Rakaydos
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1 hour ago, Green Baron said:

The rover has lasted 55 times as long as planned and successfully weathered through several sandstorms before.

 

46 minutes ago, Rakaydos said:

The rover is dead because it hasn't been to a mechanic in 15 years.

How great was the solar panel degradation? I can't remember if they had low-battery problems.
Should the Martian colonists replace their solar powerplant every 2 years if 15 is too much?
Otherwise if the panels hadn't degraded, that's no matter how old it was.

46 minutes ago, Rakaydos said:

YOUR car last without maintinance?

My car is made by NASA from the best parts existing?

(That's not against Opportunity who is/was great. That's about solar panels as an alternative for nukez).

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7 minutes ago, kerbiloid said:

 

How great was the solar panel degradation? I can't remember if they had low-battery problems.
Should the Martian colonists replace their solar powerplant every 2 years if 15 is too much?
Otherwise if the panels hadn't degraded, that's no matter how old it was.

My car is made by NASA from the best parts existing?

(That's not against Opportunity who is/was great. That's about solar panels as an alternative for nukez).

Solar panel degredation wasn't part of the conversation concerning Opportunity-  Randal Munrow joked about Opportunity lasting another hundred years.

Depending on the isotope, the solar panels actually held up better than some of the lighter radiothermal generators, that use shorter half lives.

 

As for your car not having as good of parts as NASA... why not?

Edited by Rakaydos
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