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[Another]

I think Sheb was pointing out that the site was claiming that effectively 15 umoles of charge carriers are released by that device and will pull back to the ones left inside the device of the opposite polarity with stated force.

[wierd]

Not exactly. Peizo crystals release high velocity electrons when compressed. It's what's used to make the "Spark" inside child-safe lighters. (the crystal in the gun is considerably bigger than the one in a cigarrette lighter. However, because the gun is producing ions in the bore through releasing those electrons (and then reabsorbing them on release of the trigger) randomly, the charge force at the bore is considerably less. The charge force at the BORE is 1.5c.

That's plenty to move dust around.

Here is said "POS" hard at work.

Last I checked, a styrofoam peanut weighs considerably more than a thin film of dust.

[Sheb]

And pray tell me, what atoms are those electrons released on?

[wierd]

Mars DOES have an atmosphere. Just a very thin one.

[Sheb]

You've shown us a video of a styrofoam penut falling down. Stuff fall down, that's because of gravity, not because someone is playing with a piece of plastic a feet away.

Piezo-electric don't release a burst of "high velocity electron" at random when compressed. They're not a wet sponge you can press electrons out of. What they do is move their charges so you have an higher concentration of electrons at one end of the crystal. If the two ends are close enough, this can lead to a spark or something. But you can send a cloud of electrons that you'll capture later one.

[10ebbor10]

One, the sensors. These could be anything we'd like (barometric, temperature, humidity, whatever), and there would have to be a lot of them. They'd be compact, durable, and reprogrammable to repurpose them for other things, but we'll get to that. They would be powered entirely by radio flux, possibly with a secondary radioisotope-powered transmitter in orbit, and we'd achieve that by having very long, very thin antennas attached to each.

All of these are useless for navigational purposes, but that has been said before. Additionally, your sensors are going to have a very hard time not to freeze to death, as radioflux, aside from being impossible to google without getting irrelevant results, isn't the most energetic power source.

These would unfurl as draglines - the sensor modules would be shaped like spools, grooved aerodynamically to spin as they entered the Martian atmosphere, throwing the wound antenna outwards forcefully as they descend - as they slow, the antennas would naturally start to pull more and more, putting a large amount of its momentum into rotation. There would have to be no other method slowing them, so yes, the sensor would impact with a certain amount of force.

If we made them rugged enough (with well-engineered sensors), that could actually help them find purchase in the soil once they hit. Some of them would probably fail, but we're trying to prevent the same thing from happening for colonists. It's an unknown to me, but since there's no complicated robotics, I'm reasonably certain we could work something out.

The martian atmosphere is very, very thin. It's doubtful that they'd get any meaningful spinning energy, without taking a massive (in comparison to the probe) wind catcher. Additionally, it's even less certain that it will survive. The martian escape velocity is 5 km per second. With no significant braking systems, Your impact speed would be comparable. Even if it were an order of magnitude smaller, the probe would still be destroyed.

So now we have a loose network of transmitters scattered across the surface of Mars. If you made the mission large enough (which, lacking the need for crazy heat shields and sky crane maneuvers and chutes etc etc etc, you might be able to make this system quite thorough), you would now have the beginnings of a communications and locations system. They could act as primitive relays to allow future martians an emergency comms system that would "never" fail. Because Mars has no magnetosphere, they could act as doppler weather stations for a suitably equipped orbiter (and this is also why I think that a RFID-type setup could transmit powerfully enough to work, correct me if I'm wrong) If you'd like, they could be repurposed as a great big radio telescope, which could provide for another source of data for solar activity, or just for Science. I'm sure people could think of other uses for a bunch of antennas attached to computers. It'll probably end up being Martian WIFI, which is probably a sanity saver for colonists.

Even if your probes survive, they'll likely be buried several meters deep into the ground. (Your proposals shares some similarities with a prospective project to rapidly install underground sensors ). Most will end up in small craters. Additionally connecting them toghether is going to be hard, as they'll need orbital sattelites to bound there signals too.

This is why having them be reprogrammable would be a good thing. Raspberry Pi anyone?

Raspberies, and much other customer electronics fail after consistent exposre at minus 20°C. Average temperature is -55 degrees.

Distributing this system properly would benefit from some better planning than just letting them all go at once. I would suggest a single sensor be sent down to gather weather data in the local area, and then an additional one should be dropped each time mission parameters are reached where they could be reasonably sure that the sensor would not veer off-course. If there was significant drift from wind activity during the descent, this process could be sped up, and if we notice them drifting together in certain spaces, that would be an indication of a more established wind pattern.

Martian atmosphere is not sufficiently dense to result in weather having any significant influence. The only thing you would want to watch out for is a dust storm.

What do you guys think? I just think that we can do better than another rover. Particularly now that we've found water, and philanthropists seem to be interested in dipping their toes into exploration on their own, it seems like a waste to send a nearly identical mission just because we don't feel like spending money to develop other ideas.

Honestly, the premise is flawed. A sensor network is great, but they won't survive the harsh environments. Additionally, their original purpose is useless too.

[wierd]

You can if you use a semiconductive material to prevent reflow. Essentially, a diode on either end, forcing the electrons that flow back into the crystal to come from the other side.

And yes, it does act a bit like a sponge. The valence electrons are what give the crystal its rest configuration. when compressed, valence electron repulsion pushes them out of their valences. That is where the current comes from, and why it snaps back when the mechanical energy source is released.

It is also why the crystal expands when exposed to electrical current, which is why the crystals can be used as speakers and actuators.

Additionally, said styrofoam peanut was held in place on the vinyl record via electrostatic attraction. The EM force is known stronger than the gravitational one. This is why you can pick up paperclips with magnets. The "POS" negated the electrostatic attraction of the peanut with the record. 

The electrostatic attraction of the particles to the solar collector surface is why they get totally plugged. As the weak martian wind blows the very dry particles around, they get statically charged from rubbing against each other. They then stick to the collector.  Negating that charge, will make them brush right off.

[Sheb]

"Push them out of their valence?" What the hell is that even supposed to mean? The electrons don't even leave the crystal's atoms, it's just that the internal dipole get shifted around.

[10ebbor10]

Dust on the panels isn't the only problem though. A major dust storm in the atmosphere could be far worse, reducing solar power tremendously. Can't brush that away.

[wierd]

"Push them out of their valence?" What the hell is that even supposed to mean? The electrons don't even leave the crystal's atoms, it's just that the internal dipole get shifted around.

That physically cannot happen, unless the electrons move. The redistribution of charge, happens because the electrons move.

Take your typical semiconductor, for instance.  It has one material that has extra electrons (usually a metal, like Gallium), and another that has a "hole" where an electron would like to be for pair stability, but isnt there because of charge stability. (Like arsenic.)  When an extra charge is applied to the correct side, electrons flow into the holes, but then the charge force inside the material pushes it back out. This is enough to knock an electron off of the sandwiched side with extra electrons like a newton's cradle, and out the other side.

Something similar happens inside a piezo crystal, when it is compressed. Under the physical pressure, a valence electron is displaced, and bounces the electron from the molecule next door out of place, and so on, in a game of musical chairs. Or in this case, musical valences. While this happens, the crystal takes on a new ionic charge potential, because its valences arent properly filled. This occurs because of the physical compression of the material, forcing the lattice to restructure. If you place semiconductor on the crystal, electrons will flow into it from the pressure, but then when you release the pressure on the crystal, they cant flow back in. This causes them to come in from the other side of the crystal.

[10ebbor10]

"Push them out of their valence?" What the hell is that even supposed to mean? The electrons don't even leave the crystal's atoms, it's just that the internal dipole get shifted around.

That physically cannot happen, unless the electrons move. The redistribution of charge, happens because the electrons move.

Which btw, can happen, if the metal has a ion grid or some other molecule form that allows free movement of electrons.

[Descan]

Would it be much harder to just have a transparent, wired sheet over the solar panel, and charge the sheet every so often to dislodge the dust? :v

[MetalSlimeHunt]

Not many things are going to be fully transparent to the usable spectrum of light for solar panels.

[10ebbor10]

Additionally, you have to watch out when it breaks. Prolonged activation could drain batteries and ruin the solar panel.

Edit: On a side note, I'm not sure if including a dust cleaning mechanic would be that beneficial. Both Spirit and Opportunity didn't suffer that much from the dust. The storms and other technical defects were far worse.

[MetalSlimeHunt]

Congress!