Pluto's atmosphere is a borderline exosphere, I don't expect it to have a relevant effect. But there's lots of potential from freeze-thaw erosion and even buried fluids.
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.
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.
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?
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.
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.
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;)
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.
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.
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.
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.
Indeed, I hate this "correction" when people think they're being smart by correcting "eskimo" with "inuit". Try calling a Yupik eskimo an "Inuit" and see how they take it.
I grew up in the US but live in Iceland, and there are indeed cultural differences along these lines, for places that don't have the historical baggage of certain forms of racism. I've seen Mammút go on stage several times in blackface, people couldn't understand why asian immigrants got mad at the "Tong Monitor" sketch where a standup commedian taped his eyes into a slant, there's a candy here called Sambó, etc. There's very little history of racial diversity here, it's a modern thing for the most part, and so people don't come from a background context of people using these sorts of stereotypes in association with a culture of bigotry and discrimination. People "hear" that some people get offended by this sort of stuff, but without the context, most have trouble understanding it.
I think whether people were offended really comes down to their level of familiarity with the minstrel show portrayal of african-americans. Because Jar-Jar was a classic example, every last bloody detail except being an alien (and even at that they made sure to style him with a big bottom and lips). Actually, they went even further than a typical minstrel show, adding in your standard "spear chucker" stuff as well. If a person has little familiarity with that past presentation, then I can see why they wouldn't find the Jar-Jar performance offensive. It's not about a character being intelligent or not.
Then again, we have a candy here called Sambó, so....
Why do you feel that you have to memorize them all? Do you feel compelled to memorize all of Earth's rivers or all of the named stars in our galaxy? The concept that "what I can remember all the names of" is grounds for a scientific classification is an absurdity.
And New Horizons' Alan Stern recommends - and I agree - that indeed moons that would otherwise meet the definition of being a planet except that they are moons of a planet should be seen as planetary moons. So our solar system could be said have several "planetary moons" and "dwarf planetary moons" - Earth's, the Galilean moons, Titan, Triton, maybe others. "Planet" being the general category for non-stars in hydrostatic equilibrium, "planetary" being the adjective form, "moon" being a body in orbit around something that's not a star, "dwarf planet" just being a category of planet, etc. They're all just different categorizations that you can apply where they're needed. Other systems might have other types of planetary moons, even gas giant moons.
Likewise, you should be able to have planetary bodies that aren't in orbit around anything and drift freely through space. We don't have the technology to spot them yet, but I wouldn't be surprised if the galaxy was chock full of them - why shouldn't it be? What an object orbits around doesn't define what it is. So you could have roaming terrestrial planets, roaming gas giants, roaming dwarf planets, and on and on.
Nature always likes giving us diversity. In almost every field of science, this diversity is embraced. Except apparently when it comes to the IAU and planets, on the grounds that "I couldn't memorize them all". Well, tough luck, we're going to keep finding more and more planets under any definition, and more and more diversity, with time, you can't hold out on your "I can't memorize them all" nonsense forever.
And really, why not embrace the fact that these aren't just undifferentiated hunks of rocks? Something being large enough to reaching hydrostatic equilibrium says a lot about the object. It means you start getting all sorts of geological differentiation processes, uneven heating, localized mineralization, long timeperiods to cool down, etc. It makes them very interesting places for exploration - and for the search of for life.
You know what I meant. There is no single object larger than Ceres, or even close to its size, in its neighborhood. Hence saying "If any exoplanets were outweighed by something else in the same orbit, we would have detected that other thing first". There is no "other thing" larger than Ceres in its orbit.
Neither "being dominant in its neighborhood" (which, by the way, Ceres is - its neighborhood isn't clear but it certainly is dominant), nor "being responsible for being dominant in its neighborhood" are reasonable definitions. They say nothing about what the body itself is. The concept that you could have an exact clone of Earth not be called a planet in certain circumstances - for example, orbiting the habitable zone of a much larger star, or in a much younger star system, or in a star system without Jupiter's aid - renders the whole definition an absurdity. As does the fact that these dwarf planets that we're excluding are much more similar to Earth than say Jupiter which we're including.
Seriously, the best argument they've given, and I'm not kidding, is that they don't want there to have to be hundreds of planets for people to memorize. One IAU official arguing for the current definition said something along the lines of (I could dig up the exact quote) "There's no way my daughter is going to be able to learn the names of all of the dwarf planets in school."
It's so ridiculously unscientific. And not only was it only a tiny fraction of the IAU who voted, but the vast majority of them were astronomers, not planetary scientists. This isn't a decision arrived at by the people who study planets.
Slashdot Mirror
Pluto's atmosphere is a borderline exosphere, I don't expect it to have a relevant effect. But there's lots of potential from freeze-thaw erosion and even buried fluids.
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.
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.
Really, you couldn't find that number? Under "Suppression"?
I did give you the cite. You suck at using the internet.
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?
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.
"The guy". Singular. Versus up to a couple dozen people out on a call.
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.
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.
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. ;)
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 ;)
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.
Or, we could RTFA before calling someone a "complete fucking moron". What was actually said:
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.
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.
Not according to the IAU and their definitions that one can only presume were conceived by a flock of drunken geese.
What's more interesting is how few there are (on both bodies).
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.
Whatever will people in the Northern Mariana Islands do with their time without net access?
Indeed, I hate this "correction" when people think they're being smart by correcting "eskimo" with "inuit". Try calling a Yupik eskimo an "Inuit" and see how they take it.
Interspecies even - for example, Loki was the mother of Sleipnir ;)
I grew up in the US but live in Iceland, and there are indeed cultural differences along these lines, for places that don't have the historical baggage of certain forms of racism. I've seen Mammút go on stage several times in blackface, people couldn't understand why asian immigrants got mad at the "Tong Monitor" sketch where a standup commedian taped his eyes into a slant, there's a candy here called Sambó, etc. There's very little history of racial diversity here, it's a modern thing for the most part, and so people don't come from a background context of people using these sorts of stereotypes in association with a culture of bigotry and discrimination. People "hear" that some people get offended by this sort of stuff, but without the context, most have trouble understanding it.
Really? The only thing they left out was the menorah.
I think whether people were offended really comes down to their level of familiarity with the minstrel show portrayal of african-americans. Because Jar-Jar was a classic example, every last bloody detail except being an alien (and even at that they made sure to style him with a big bottom and lips). Actually, they went even further than a typical minstrel show, adding in your standard "spear chucker" stuff as well. If a person has little familiarity with that past presentation, then I can see why they wouldn't find the Jar-Jar performance offensive. It's not about a character being intelligent or not.
Then again, we have a candy here called Sambó, so....
Yoda and Ackbar were white? And displaying their sexuality onscreen?
Wow, I must have been hammered when I was watching those movies...
You really think these people won't switch to being mad about ripping up untouched asteroids?
You really think they'll be fine with all of the rocket launches that would take?
Why do you feel that you have to memorize them all? Do you feel compelled to memorize all of Earth's rivers or all of the named stars in our galaxy? The concept that "what I can remember all the names of" is grounds for a scientific classification is an absurdity.
And New Horizons' Alan Stern recommends - and I agree - that indeed moons that would otherwise meet the definition of being a planet except that they are moons of a planet should be seen as planetary moons. So our solar system could be said have several "planetary moons" and "dwarf planetary moons" - Earth's, the Galilean moons, Titan, Triton, maybe others. "Planet" being the general category for non-stars in hydrostatic equilibrium, "planetary" being the adjective form, "moon" being a body in orbit around something that's not a star, "dwarf planet" just being a category of planet, etc. They're all just different categorizations that you can apply where they're needed. Other systems might have other types of planetary moons, even gas giant moons.
Likewise, you should be able to have planetary bodies that aren't in orbit around anything and drift freely through space. We don't have the technology to spot them yet, but I wouldn't be surprised if the galaxy was chock full of them - why shouldn't it be? What an object orbits around doesn't define what it is. So you could have roaming terrestrial planets, roaming gas giants, roaming dwarf planets, and on and on.
Nature always likes giving us diversity. In almost every field of science, this diversity is embraced. Except apparently when it comes to the IAU and planets, on the grounds that "I couldn't memorize them all". Well, tough luck, we're going to keep finding more and more planets under any definition, and more and more diversity, with time, you can't hold out on your "I can't memorize them all" nonsense forever.
And really, why not embrace the fact that these aren't just undifferentiated hunks of rocks? Something being large enough to reaching hydrostatic equilibrium says a lot about the object. It means you start getting all sorts of geological differentiation processes, uneven heating, localized mineralization, long timeperiods to cool down, etc. It makes them very interesting places for exploration - and for the search of for life.
You know what I meant. There is no single object larger than Ceres, or even close to its size, in its neighborhood. Hence saying "If any exoplanets were outweighed by something else in the same orbit, we would have detected that other thing first". There is no "other thing" larger than Ceres in its orbit.
Neither "being dominant in its neighborhood" (which, by the way, Ceres is - its neighborhood isn't clear but it certainly is dominant), nor "being responsible for being dominant in its neighborhood" are reasonable definitions. They say nothing about what the body itself is. The concept that you could have an exact clone of Earth not be called a planet in certain circumstances - for example, orbiting the habitable zone of a much larger star, or in a much younger star system, or in a star system without Jupiter's aid - renders the whole definition an absurdity. As does the fact that these dwarf planets that we're excluding are much more similar to Earth than say Jupiter which we're including.
Seriously, the best argument they've given, and I'm not kidding, is that they don't want there to have to be hundreds of planets for people to memorize. One IAU official arguing for the current definition said something along the lines of (I could dig up the exact quote) "There's no way my daughter is going to be able to learn the names of all of the dwarf planets in school."
It's so ridiculously unscientific. And not only was it only a tiny fraction of the IAU who voted, but the vast majority of them were astronomers, not planetary scientists. This isn't a decision arrived at by the people who study planets.