todofwar

What's 14 minutes worth?

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So getting a human to land on Mars and come back is very hard. But here's an idea for a less sexy mission, but still sends people to Mars and if anything gets us some practice. 

Apparently, a mission to Mars will involve 18 months on Mars itself. That's a tall order, but theoretically doable. What if, instead of landing the astronauts, you leave them in orbit and land one rover per astronaut. Each one with certain specialized equipment. Each astronaut then spends 18 months working long hours driving them around, no need to tie up the DSN. You have one or more land close to a rocket capable of docking with your orbiting station in LMO so at the end of the mission you can bring back some samples. 

Now, we don't get that sexy shot of humans standing on another world, but in terms of science we would have three curiosities running around, probably something more sophisticated. The real utility of this project comes from that 14 minute delay no longer being a problem. Any possible benefit of having humans on Mars with less risk, and without having to go all the way down to the surface. Which means it will be easier to bring them home. Which gets to the title of this thread, what is that 14 minutes (and a free DSN for other missions) worth? And, this tech can possibly be applied to longer missions to Jupiter or Saturn, where the delay time is more severe so you get a bigger benefit.

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Its not an entirely new idea, you could add exploring the moons of Mars to the mix so the astronauts can plant the flag for expereince.
Main issue is however that the current rovers are under powered and slow as they have to cope with the signal delay anyway. 
If you want no signal delay you want an faster rover this require an nuclear reactor driving up weight. 
 

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Teleoperation from orbit has been talked about for quite a while. The question is, what do you gain ?
Your astronauts are only going to be driving those robots for 8 hours per day or so, for something like 6 months. A robot operated from Earth can function for several years and isn't constrained by a single operator's biological cycle. It can also be driven by a whole team of scientists who can provide more input into what to do next.

There really isn't much to gain in operational terms. Robots are getting smarter, so there is no need to manually drive them. You can just enter a set of destination coordinates and it can navigate itself there while you sleep. Who cares if it takes 5 years instead of 6 months to gather the same amount of science? Mars isn't going anywhere.

The reason rovers are slow is because of size, power, and weight constraints. If you can send a 500-ton manned spacecraft to drive four 1-ton rovers, then you could also send a hundred 5-ton rovers for the same budget and you would cover a much wider area and get much more science.

Edited by Nibb31

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The ability for rovers to self drive is only going to increase over time as self-driving matures, too.

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4 hours ago, Nibb31 said:

Teleoperation from orbit has been talked about for quite a while. The question is, what do you gain ?
Your astronauts are only going to be driving those robots for 8 hours per day or so, for something like 6 months. A robot operated from Earth can function for several years and isn't constrained by a single operator's biological cycle. It can also be driven by a whole team of scientists who can provide more input into what to do next.

There really isn't much to gain in operational terms. Robots are getting smarter, so there is no need to manually drive them. You can just enter a set of destination coordinates and it can navigate itself there while you sleep. Who cares if it takes 5 years instead of 6 months to gather the same amount of science? Mars isn't going anywhere.

The reason rovers are slow is because of size, power, and weight constraints. If you can send a 500-ton manned spacecraft to drive four 1-ton rovers, then you could also send a hundred 5-ton rovers for the same budget and you would cover a much wider area and get much more science.

you might have a crew of several operating in shifts. so one rover might have 2 or 3 crew members assigned to operate each one. you would of course needs a couple comm sats to keep the rovers in communications range, some latency but not a lot. its entirely possible those comm sats are just end of mission spacecraft remnants floating around in mars orbit. you could also have 2 or 3 different control sats in orbit managing several rovers at once, and they switch to keep the latency as short as possible.

that said it really doesn't make sense for exploration. its cheaper to send a rover than a multi-module crewed mission and you can get years out of those. where it does make sense is to prep for a colony (rovers are manufacturing building materials, habitats, collecting consumables, and setting up infrastructure for eventual human habitation). these kind of things would benefit from fast turn around and decision making and execution takes minutes or seconds instead of hours. something like that might be used in asteroid mining. you might have a base station somewhere in the asteroid belt tele-operating multiple missions on many asteroids at once.

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1 hour ago, Nuke said:

you might have a crew of several operating in shifts. so one rover might have 2 or 3 crew members assigned to operate each one. you would of course needs a couple comm sats to keep the rovers in communications range, some latency but not a lot. its entirely possible those comm sats are just end of mission spacecraft remnants floating around in mars orbit. you could also have 2 or 3 different control sats in orbit managing several rovers at once, and they switch to keep the latency as short as possible.

Remember that Mars has a day/night cycle too. There isn't much point in exploring at night time, for obvious visibility and power issues. Also, having a crew of 2 or 3 to control each rover dramatically increases the total cost of your mission.

 

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6 hours ago, Nibb31 said:

Teleoperation from orbit has been talked about for quite a while. The question is, what do you gain ?
Your astronauts are only going to be driving those robots for 8 hours per day or so, for something like 6 months. A robot operated from Earth can function for several years and isn't constrained by a single operator's biological cycle. It can also be driven by a whole team of scientists who can provide more input into what to do next.

Except they are constrained by power generation and needing good lighting conditions in general, so 8 hours a day is probably all you can get anyway. And it will be 18 months on Mars, according to Mike Massimino. 

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4 minutes ago, todofwar said:

Except they are constrained by power generation and needing good lighting conditions in general, so 8 hours a day is probably all you can get anyway. And it will be 18 months on Mars, according to Mike Massimino. 

It depends on the mission profile, the transfer time, and the launch windows, but the actual time on Mars (or in Mars orbit in this case) varies from 3 months to several years.

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14 hours ago, Nibb31 said:

Teleoperation from orbit has been talked about for quite a while.

For a moment there, i actually thought you had written 'teleporting'!  I must stop watching Star Trek.

 

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On 9/23/2016 at 1:45 AM, Nibb31 said:

Teleoperation from orbit has been talked about for quite a while. The question is, what do you gain ?
Your astronauts are only going to be driving those robots for 8 hours per day or so, for something like 6 months. A robot operated from Earth can function for several years and isn't constrained by a single operator's biological cycle. It can also be driven by a whole team of scientists who can provide more input into what to do next.

There really isn't much to gain in operational terms. Robots are getting smarter, so there is no need to manually drive them. You can just enter a set of destination coordinates and it can navigate itself there while you sleep. Who cares if it takes 5 years instead of 6 months to gather the same amount of science? Mars isn't going anywhere.

The reason rovers are slow is because of size, power, and weight constraints. If you can send a 500-ton manned spacecraft to drive four 1-ton rovers, then you could also send a hundred 5-ton rovers for the same budget and you would cover a much wider area and get much more science.

The magic of unmanned space exploration: more effective than sending humans in 70% of instances, cheaper, safer . . . I would imagine that nearly everything of any real scientific merit that was done by the Apollo missions on the surface of the moon 40 years ago, today could be done for a fraction of the cost/risk using robots. Indeed, the data collection capacity for Curiosity or Opportunity or any of the next generation of robot missions probably far exceeds what was doable (or done) by the entire Apollo program.

None of which would be that big of a deal IF the Apollo program had been more than a gigantic PR stunt, with spillover benefits in myriad disciplines. I suppose those spillover benefits more than justify the missions in hindsight, and in foresight. I'm just disappointed that, there is ZERO continuity between the giant leap of ~40 years ago, and today.

If you are going to make big plans, do it in a sustainable way; do it in a way that maximizes the likelihood of continued funding, continued public and governmental support, continued benefit to humankind and continuation of the vision.

Of course there is a point at which humans need to be present. But in my--perhaps somewhat naive opinion--we are many decades from reaching that point, either with respect to the Moon, Mars, the asteroids, or even Low Earth Orbit. LEO being perhaps the single exception: humans MIGHT be more efficient at building some things I reckon. Research, not just data collection but _research_ is almost certainly done by humans, so to the extent the ISS is producing significant research, it justifies the costs and risks of sending humans up there I suppose.

Edited by Diche Bach

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Put some GPS (APS? MPS? whatever) sats around Mars and equip these rovers with the latest self-driving technology. You won't need people in orbit to drive them. You won't need anyone to drive them. You'll just send them some waypoints and they will drive themselves wherever you want them to go.

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1 hour ago, KerbMav said:

If you are already there you might as well land.

Only if you have an extra 3000m/s of dV.

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I think they should launch with more supplies one mission needs and leave their HAB on orbit. First mission would mainly orbit for a some time and take pictures, burn towards home and tether their spent stage to give some sense of gravity. They'd also bring station hub there. Other missions could bring more supplies than they need and more HABs and so Mars station would get stocked up with all goodies necessary and with more room. Since other missions wouldn't need to carry heavy hub part they could carry rovers or more fuel for interesting stuff like Mars moon landings and eventually Mars landing.

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On 23/09/2016 at 7:40 AM, magnemoe said:

If you want no signal delay you want an faster rover this require an nuclear reactor driving up weight. 

 

On 23/09/2016 at 8:45 AM, Nibb31 said:

The reason rovers are slow is because of size, power, and weight constraints.

Would power problems be solved by parking larger "mothership/station" on synchronous orbit? It could have massive solar panels and it could use laser to recharge rovers almost all the time. Once it's time to go home, leave solar plant on orbit for possible future use with surface missions in mind. Such space lasers have been proposed to partially solve energy needs in carbon-free manner. It wouldn't really make sense on Earth but it might solve some issues with Mars.

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4 minutes ago, ImmaStegosaurus! said:

 

Would power problems be solved by parking larger "mothership/station" on synchronous orbit? It could have massive solar panels and it could use laser to recharge rovers almost all the time. Once it's time to go home, leave solar plant on orbit for possible future use with surface missions in mind. Such space lasers have been proposed to partially solve energy needs in carbon-free manner. It wouldn't really make sense on Earth but it might solve some issues with Mars.

This would probably be heavier than landing an rover with reactor. Laser would have to deliver many kilowatt, and have an very long range, think a laser weapon but able to fire for days. 
This had been more interesting for powering an flying drone as power demand is far less and its critical to keep weithyg down. 

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I don't think such an expensive mission for so little gain makes sense. For that price, at the very least I'd want samples returned to Earth.

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18 minutes ago, Beowolf said:

I don't think such an expensive mission for so little gain makes sense. For that price, at the very least I'd want samples returned to Earth.

Sample return was listed as an objective. 

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On 9/24/2016 at 9:26 PM, todofwar said:

Sample return was listed as an objective. 

Whoops! So it was, sorry.

 

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Oops misunderstood what you mean.

That would cost more per rover than landing Curiosity. And the only thing you get is no signal delay.

Edited by Veeltch

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