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Comment Re:Young surface (Score 5, Interesting) 108

There's a number of potential fluids at pluto-range surface temperatures - nitrogen, neon, etc. The problem is pressure - but it doesn't take all that thick of an ice pack to get the requisite pressure - I calculate 13-18 meters minimum for nitrogen (depending on Pluto's current pressure), which is only about the weight of a meter of ice on Earth. It has to float, of course, and unlike water their ices sink... when at 100% density. But they'll have pore space in almost any realistic situation. And there's always lighter types of snow, such as methane snow, which don't require any pore space at all to float.

More to the point, anywhere that these sorts of snow preciptate out deep enough, in the right temperature conditions, they'll melt on the bottom. If the ice is condensed on a slope, the liquids will try to flow out. If they find a way out, they'll freeze, pressure will rebuild into it bursts open, then a refreeze, and so on, like pillow lava spreading on Earth - possibly with cryogenic equivalents of lava tubes as well. Where there's no path for liquids to flow, you could have something akin to arctic sea ice.

Note that pressure is only part of the key, temperature matters too. But these sort of conditions are quite plausible on Pluto. And more to the point, since there's a range of potential liquids at Pluto temperatures but with different properties, you could have some rather complex interactions with dramatically different properties at different depths and massive events when the temperature or pressure on the surface changes beyond a key point.

Oh, I almost forgot about this effect, which could be a serious weathering agent. Freezing nitrogen can be a bit.... dramatic. ;) Here you can see some of the craziness it does when going between phases, starting around 50 seconds in. Certainly looks like something with significantly more erosion potential than water ice freeze-thaw on Earth.

Comment Re:Flame retardant payloads? (Score 1) 87

Yes, they make many, many runs. And that doesn't apply here... why? Especially given that they're looking at, what, 17 drones available?

A drone the size of a king-sized bed doesn't have to just "dump"; you're talking a payload in the ballpark of maybe 20 kilos. That's more than enough to have a ~120 PSI pump that can break windows. Or a fire grenade launcher, or many other options.

Comment Re:Opening themselves up to liability? (Score 1) 87

We're not talking about completely dousing a housefire. We're talking about buying a small amount of time until ground crews can get there. And I notice you have no comment about the analogy with aircraft-based wildfire suppression.

An 18 rotor aircraft designed to carry a person for up to 20 minutes is not really comparable with a 3 fan long endurance surveillance drone.

1. Smaller numbers of larger rotors are more efficient than larger numbers of smaller rotors.
2. Endurance is a function of payload. So if you want to operate in a surveillance role, leave behind the fire suppression hardware. If you want to operate in a fire suppression role, go there, discharge your suppression hardware, and go back for recharge or battery swap and refill. There are to be, what, 17 drones operating?

Comment Re:Worst possible example. (Score 1, Insightful) 87

If you honestly think that such a thing even happens you are as foolish as him. You are creating a straw man with an event that's as rare as unicorn sightings.

If you honestly think that rescue workers don't get multiple calls at the same time to deal with and that such a concept is "as rare as unicorn sightings" then you need to spend some more time with rescue workers.

Many of these budgets have fixed costs, for example you have 20 firefighters sitting around 24/7/365 (multiple shifts). And these firefighters aren't in new york responding to calls every few minutes. They spend 90% of every day sitting on their ass, just like every other sub-urban/rural firefighter.

The Macon-Bibb Fire Department gets 13 thousand calls per year and has to respond to all of them.

But why don't you go down there and call them a bunch of lazy hicks who sit on their ass all day, I'm sure they'll appreciate that.

You seem to think that drones fly themselves. That the guy sitting there flying the drone..

"The guy". Singular. Versus up to a couple dozen people out on a call.

You also seem to be of the view that drones are miraculous and can spot people in a gutter or a lost child in a forest.

Given that these are the reasons that police and rescue services pay for helicopters, which are much more expensive, yes, finding things from the air with an IR camera is a demonstrably beneficial activity.

Drones aren't miracles.

Nope. What they are is cheap helicopters with minimal pre-launch delays and in which that the pilot doesn't have to be physically inside. Which is in all regards a great thing for emergency services.

Comment Re:Make it friendly-looking (Score 1) 87

It should refer to everyone as "citizen" when giving them orders, with each sentence containing a mix of friendly and not-so-friendly words. Examples:

CITIZEN, PLEASE RETURN TO YOUR DWELLING AT ONCE.
CITIZEN, WE REQUEST THAT YOU COMPLY IMMEDIATELY.

Double points if whatever display it uses as its face is jarringly discordant with the implicitly (or explicitly) threatening commands it's giving. ;)

Comment Re:Opening themselves up to liability? (Score 1) 87

A drone the size of a king-sized bed probably has a payload in the ballpark of maybe 20 kilos - the weight of a refrigerator**. We're not talking about a little kitchen fire extinguisher here. You could haul around a 120psi hose system powerful enough to break windows with that kind of payload.

"thousands of gallons of water to suppress it"? Given that those are the sort of quantities planes drop on wildfires (per run) over several acres per run in order to suppress them, you're thinking too big.

** - I'd call this the size of 2 or 3 king-sized beds and it carries a freaking person ;)

Comment Re:Flame retardant payloads? (Score 1) 87

If you picture it as "aircraft with 1-2 orders of magnitude more payload are used to control wildfires", the concept of a drone-mounted fire suppression for house-scale fires to buy time for ground fire crews really doesn't sound that unrealistic. It's not going to put out a 3-alarm blaze, but it's going to buy you time.

Comment Re:Worst possible example. (Score 1) 87

So most fire alarms are false alarms so the solution is to delay deployment of the fire department until a drone can see if the fire is real? He can't really be suggesting that because that would mean he's a complete fucking moron.

Or, we could RTFA before calling someone a "complete fucking moron". What was actually said:

Maybe you send one vehicle to monitor it and can send the other (firefighters) to a major wreck on a highway.

He's not saying "ignore fires because we have drones". He's saying "use drones to be able to use your limited resources more intelligently" - for example, focusing on getting that jaws-of-life to a potentially critically injured car accident victim rather than diverting to a probable false alarm house fire. The fact is that budgets are limited and you can't have an infinite number of rescue workers responding to everything. There's tons of different tasks to which your limited number of workers' attentions can be allocated, and they have different payoffs in terms of helping the public, but assessing the potential payoff requires intelligence. Having additional intelligence at your disposal can help allow your finite resources be allocated toward more productive purposes. And compared to the salaries and overheads of humans, drones are very cheap. And their utility stretches across multiple departments - police, fire, paramedics, search and rescue, etc. If you're collapsing in a gutter at night with a heart attack, how long do you want the paramedics to have to spend searching for you while your brain cells die? If your child gets lost in the woods, how long do you want them to be out there alone? If call in to report someone trying to break into your house or run away with your stuff, how long do you want it to be before they find themselves with a police-controlled camera pointed at them?

And beyond all that, drones can get you the information you need fast. The ability to get an IR camera up to an altitude with a line of sight to your target in a matter of seconds, and all the way to the location in just a couple minutes, is of no small benefit. A drone could probably confirm a major fire before your firefighters could even get suited up.

Comment Re:Opening themselves up to liability? (Score 1) 87

If the drone is the size of a king sized bed, I don't see why they couldn't outright include some degree of fire suppression hardware - not enough to put out a major building fire, but a couple dozen kilos of fire suppression system rapidly deployed to a fire would certainly not go awry until ground crews can get there.

But anyway, the example given was when the fire department has a call for a fire and a call for a major accident on the freeway - the drone could check out the probable false alarm while the fire crew heads out to the freeway. If there's a real fire, they can divert. Since the drone would use an IR camera, it should be able to tell if there's actually a fire from quite a ways away - I would expect in many cases it'd probably just have to clear the trees and surrounding buildings (a matter of seconds) to get line of sight; fires kick off a ton of IR. And if it doesn't see anything right away and has to get closer for a better look? Then indeed the odds are higher that it is a false alarm, and even if it is real, it's certainly not some huge out-of-control blaze.

And firefighting was just part of it. They also give examples of, say, getting a 9-11 call for someone at night having a heart attack. Instead of wasting precious minutes searching for them, the IR camera could pick up exact location for the medical crews.

I'm someone who really hates the whole "police state" deployment of CCTV cameras everywhere, like they do in Britain. But this strikes me as a very good use of technology, driven by genuine public interest rather than paranoia or fine collection.

Comment Re: Bigger than the Grand Canyon Taller than Evere (Score 1) 77

While it doesn't have water near the surface (possibly a fairly deep subsurface ocean), there are liquids that could exist near the surface. The pressure fluctuates wildly, but at today's pressure, it would take about 13 meters of slightly-porous nitrogen ice (more of methane ice) for nitrogen to be able to reach its triple point. That's the equivalent of the weight of less than 1 meter of ice on Earth, so not something abnormally strong or compacted. Additionally, there's all sorts of things that can be liquids at different temperatures and pressures... there could be some rather complicated fluid interactions as depth increase, and they'd change over time.

That's not saying that there are liquids right now - and barring some sort of eutectic effect, I wouldn't expect to see any on the surface due to the low pressure. But there could be something akin to the earth equivalents of sea ice or rivers with frozen surfaces, and not all that deep.

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