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Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

nytimes.com

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Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#221

Post by yellowapple »

ceejayoz wrote: post #56
thomasfortes wrote: post #52

Earlier quoted context omitted.

Steve Squyres from Cornell answered something kinda related on the jpl channel today[0]. "If you had the opportunity to bring a hundred and eighty kilograms of stuff back from the surface of Mars, the last thing I wanna bring is something I know exactly what is made of." Opportunity did her mission amazingly and is resting in peace in the place where she was designed to be. We learned a lot from her and her sister mi…

I do hope some future Mars colony goes and collects it for the Martian wing of the Smithsonian, though.

No. We're going to build museums - and cities - around the rovers, and the cities will be named after the rovers.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#222

Post by RobLach »

tomp wrote: post #205
stoops wrote: post #123

Earlier quoted context omitted.

Sounds like that person doesn't really understand that NASA is a political entity and the Public Relations of an ongoing successful mission is more valuable long term than more scientifically pragmatic experiments in the immediate.

Sounds like s/he perfectly understood that, but still didn't like it. Often (always?) politics get in the way of actually getting things done in a smart fast efficient manner.

Politics also affords the collective resources to engage on such projects. It's more chicken-egg than most think.

Not to mention, science without proper PR has a disastrous level of near-term utility. See: climate science

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#223

Post by classicsnoot »

sametmax wrote: post #198
classicsnoot wrote: post #92

Earlier quoted context omitted.

Your recollection is correct. Consider too the dust accumulation predictions for the moon landing. It would appear that we (as humans) are not very good at dust estimates (dustimates?). This is reinforced by the continuing struggle/inability to manufacture dirt. As an avid composter with a ton (lol sorry) of experience, I can make you hummus for days. I can turn 90% of your organic household waste into growth medium,…

Jumping on the opportunity to have somebody who knows about those things. I used to have a huge garden, and made a compost by barely dumping anything organic on a big pile. It worksed great: low maintenance, never one problem, plenty of compost produced. I now live in a flat, and have composter using worms. I can't make it practical for the love of me. If I put it inside, I get flies, no matter how much carbonated ma…

Definitely! First off, I am biased in my compost preferences and it is always good to hear different opinions. Second, what works for one fails for another, so no sense in throwing more effort into a process that isn't working.

On to your situation. In home composting is always tricky. My wife and I do indoor/outdoor because we have a yard. In your situation, I'd advise against vermicomposting for the same reasons you listed. I was the technical manager for an enterprise vermicompost startup. Our facility was a rowhouse basement and the owner of the property was a founder. Flies are unavoidable, as is the occasional vermischwitz. They are fragile guys and minor mistakes have major consequences. The exact ratios escape me, but 1lb of healthy, mature red wigglers can consume half a pound of Green (fresh) cellulose in a day or two. We were engineering soil additive, so we supplemented heavily with Gray (dead) cellulose (cardboard, paper, etc.) In an attempt to hit profitable output. I will spare you the further details of our failure. Suffice to say that vermiculture is tricky in the best circumstances.

My suggestion to you is twofold: use the Bokashi Method (https://www.planetnatural.com/composting-101/indoor-composti...) and find a friend with a garden to offload your Bokashi Tea. That link is one of the first hits on Google (read: not vetted) because if you go this route you are going to be reading a lot and there are many roads to Rome.

This is very short due to medium, but if you'd like to discuss in depth and at length I'd be more than happy to. Both composting and waste neutralization are passions of mine. Just let me know how to contact you should you desire.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#224

Post by classicsnoot »

emiliobumachar wrote: post #192
classicsnoot wrote: post #92

Earlier quoted context omitted.

Your recollection is correct. Consider too the dust accumulation predictions for the moon landing. It would appear that we (as humans) are not very good at dust estimates (dustimates?). This is reinforced by the continuing struggle/inability to manufacture dirt. As an avid composter with a ton (lol sorry) of experience, I can make you hummus for days. I can turn 90% of your organic household waste into growth medium,…

Your main point stands, but, for terraforming purposes, a decade is a very short time period.

In terms of exoplanetary interchange, time recedes and tonnage expands as the concern. Without a space elevator or MAC transfer solution, you'd be effectively FedExing teacups of dirt to a green house in a Sahara contained on Antarctica... on Mars.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#225

Post by FrojoS »

torpfactory wrote: post #176

You know the craziest thing about all of the mars exploration programs is to me? The first time there is an entire full-up test of the system is live, AT MARS. There isn't a good way to test the entire entry descent and landing sequence because the earth's atmosphere is so different than mars. I know NASA works hard to test parts of it in the vicinity of earth, but I can't imagine designing something so complicated (…

I've actually read, that the upper part of the atmosphere, where a returning Falcon 9 booster does retro burns to slow down, is similar to Mars (in terms of pressure I guess).

edit: found a paper on the topic https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201700...

also: https://arstechnica.com/science/2016/04/spacex-has-already-d...

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#226

Post by ezconnect »

trothamel wrote: post #172
Retric wrote: post #87

Earlier quoted context omitted.

That story is very much over sold. They defiantly designed the things with a longer lifespan in mind. NASA simply had more reasonable minimum specks so if they died on day 220 nobody would call the program a failure.

Sort of. I think the book "Roving Mars" covers this the best. They were worried about a dust storm like the one that killed Opportunity, so they designed the rover to last 90 days even in the pitch darkness of a dust storm. To make sure they'd succeed even in this worst case, they added two additional petals worth of solar panels (IIRC, about a 50% increase in area) to the MERs. Reading a contemporary description, th…

I think they solve the power problem by bringing a nuclear reactor as the main power source.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#228

Post by torpfactory »

FrojoS wrote: post #225
torpfactory wrote: post #176

You know the craziest thing about all of the mars exploration programs is to me? The first time there is an entire full-up test of the system is live, AT MARS. There isn't a good way to test the entire entry descent and landing sequence because the earth's atmosphere is so different than mars. I know NASA works hard to test parts of it in the vicinity of earth, but I can't imagine designing something so complicated (…

I've actually read, that the upper part of the atmosphere, where a returning Falcon 9 booster does retro burns to slow down, is similar to Mars (in terms of pressure I guess). edit: found a paper on the topic https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201700... also: https://arstechnica.com/science/2016/04/spacex-has-already-d...

I had heard about them doing some study of using an inflatable heat shield and testing in earth's upper. I guess it could be used for Earth or Mars. Neat!

Link: https://www.youtube.com/watch?v=ojgDZZIsWA4

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#229

Post by jelliclesfarm »

classicsnoot wrote: post #223
sametmax wrote: post #198

Earlier quoted context omitted.

Jumping on the opportunity to have somebody who knows about those things. I used to have a huge garden, and made a compost by barely dumping anything organic on a big pile. It worksed great: low maintenance, never one problem, plenty of compost produced. I now live in a flat, and have composter using worms. I can't make it practical for the love of me. If I put it inside, I get flies, no matter how much carbonated ma…

Definitely! First off, I am biased in my compost preferences and it is always good to hear different opinions. Second, what works for one fails for another, so no sense in throwing more effort into a process that isn't working. On to your situation. In home composting is always tricky. My wife and I do indoor/outdoor because we have a yard. In your situation, I'd advise against vermicomposting for the same reasons yo…

I would love to be able to connect re composting. My email is my user name at gmail. Thanks.

Re: Nasa’s Mars Rover Opportunity Concludes a 15-Year Mission

#230

Post by jessriedel »

Rebelgecko wrote: post #146
jessriedel wrote: post #109

Earlier quoted context omitted.

What's the limiting factor on just running with reduced staff support? (Honest question.)

A small handful of people can still easily cost millions of dollars per year. And DSN time to talk to the rovers is expensive, probably in the neighborhood of $2,000 per hour.

$5M a year seems like it would be very reasonable. The original 90-day price tag was $820M, and they've spent an additional ~$200M over the past decade and a half. Maybe it's really not worth it to spend $5M/year to extend the life further, but the scientific returns would have to be quite severely diminishing.
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