Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. ×

Comment Re:Maybe (Score 1, Insightful) 197

There's a lot of words but most of the points don't seem to make a lot of sense.

1. "Adjective nouns" need to have similarity to "noun" but aren't necessarily a subset. Gummy bears aren't a subset of bears either.

2. I'd like to see a citation on this. I highly doubt that you can simulate the formation of a solar system where multiple Mars analogues can coexist in the same orbit over billions of years without an accident happening to one of them.
Alone the fact that neither of the terrestrial planets have an orbital buddy tells us a lot about the chance of that happening.

3. In a geological sense yes. But the current definition of planets is based on orbital mechanics, after which Earth is a lot closer to Jupiter than to Ceres/Pluto.

4. Hydro-static equilibrium as a dividing line is way worse. There are roughly 100 TNOs where we don't really know whether they are elliptical. We'd have to visit each and every one of them with a probe just to put them in the proper category.
Meanwhile, it's completely clear which bodies qualify for the "clearing its orbit" rule. All currently qualifying planets have roughly 99% or more of the mass in their orbit in themselves. Ceres has 30%. Maybe there'll be an edge case eventually (Planet X or some Exoplanet) but that's a thing we can deal with in the future.

5. The definition should be mutable. Why should a planet that gets ejected keep counting as a planet?

6. I highly doubt life could form in a non-cleared orbit. There'd be late heavy bombardment style impacts all the time scouring the surface.
As for a life bearing celestial in orbit around another (gas giant) planet: I don't think anybody feels bad about calling that one a moon? As in "Yavin 4".

7. "Within each other's periapsis and apoapsis" seems like a reasonable enough definition that neither Ceres nor Pluto qualify for.

8. Yes that's silly but that'll probably be changed easily enough and has no effect on Pluto.

9. How are you planning to ascertain hydro-static equilibrium for an exoplanet if we can't even do it for Varuna.

etc etc the later points get even wordier and more politically minded.

Comment Re:how about the obvious definitions? (Score 2) 197

The problem with that definition is that it'd include a lot of random TNOs. We'd be up to like 15 planets by now, with an additional maybe 100 yet to be found in highly eccentric orbits, and probably tens of thousands more in the Oort cloud. In my opinion, those rocks hardly belong in the same category as Jupiter and Mars.

Also, if that definition gets chosen you can look forward to decades of drama after every new TNO discovery about whether that object is in hydro-static equilibrium or not. Can you imagine if a Chinese astronomer finds such an object barely on the edge of the definition, but we only have a few single pixels of images available, and the IAU needs to make a finding on whether it qualifies as a planet or not?

Comment Re: Two questions (Score 1) 69

Israel's budget is $70b, and they receive $3b in direct government aid from the US. That creates a whole bunch of weird incentives that pop up when a large amount of the money you spend doesn't come out of your own pocket. And I doubt that since the end of the Soviet Union, there is any other country that finances 5% of its operation through foreign aid. Even Venezuela currently only gets less than $100m a year total, and the Chinese probably aren't spending a lot of money on North Korea either although it's of course impossible to get real numbers there.

Comment Re:This is what you get with low cost manufacturin (Score 1) 166

People aren't going to shit into the town well, but even there I am willing to question how far that is because they are aware of the consequences of their action, and not simply because they knew they'd get a beating from all the other townspeople. There'd certainly be people that would readily do so as long as there was another well somewhere else that they could drink out of.

But even that common sense you describe seems to go away really quickly as soon as the damage isn't completely obvious. In many places it's absolutely nothing unusual if you throw your trash into the same ocean the fish you're eating for dinner comes out of. Abstract that even further to ppms of invisible gases in a million cubic kilometers of air and even some people with doctorates seem to have trouble understanding the consequences.

Clearly, a dictatorship cannot handle this issue as well as a democracy can. The people in power are way too close to those few who benefit from lax environmental standards way more than they'd benefit from better environmental conditions. But as you noted, privatization is not an option for fleeting resources like water or air.

Comment Re:This is what you get with low cost manufacturin (Score 1) 166

I find your segue into the anti-government rant a bit weirdly placed. Air quality is a textbook example of a "problem of the commons" situation - probably the biggest of them all because the atmosphere is literally one giant planet-spanning commons that everyone draws from.

And personally I cannot see a solution to the problem of the commons other than through goverment. Because even if people do realise they are also hurting themselves by polluting, it doesn't change the fact that a benefit from polluting less will be shared by everybody, while the costs of doing so are only applied to them. A rational actor will therefore always make the problem worse. Nobody wants to be the only guy on the block that spends double the money for oil heating, while still taking in 99% of pollution because everybody else is still on coal.

In a government, people can agree on reasonable restrictions that everybody needs to abide by to make the situation better. If you can outright make coal heating illegal, then people can expect 50% of pollution for double the money, and might even enjoy that change.

Now I do agree that there's a big caveat here and a possibility that such regulation would be overbearing, but I find it kind of silly to believe that we could have successfully made all the environmental progress of the past few decades in the west without the hammer of big government behind it.

Comment Re:Well... (Score 1) 129

The following command doesn't need admin rights and deactivates Powershell signing for the current process:
Set-ExecutionPolicy -Scope Process -ExecutionPolicy Bypass
That's sufficient to allow Powershell to do the same nastyness that .cmd and .exe files are allowed to by default though.

Powershell signing is a badly thought out security mechanism that really does not do anything.

Comment Re:How can this be competitive? (Score 1) 121

Musk does have a bit of a habit of announcing Sci-Fi projects in grand strokes but never actually explaining how he's going to fix the problems that plagued earlier attempts.

The relaunchable rockets are the probably most realistic goal he's currently trying to achieve and that still hasn't worked out - the only rocket they've actually attempted to launch a second time blew up. And this after NASA had been doing the relaunching space transport thing for decades, and had to come to the conclusion that even if the Space Shuttle technically worked, it was probably more expensive than using regular discardable rockets would've been.

Now he's also trying to build a supersonic train, quadruple the number of satellites currently in space in five years, start up asteroid mining, and then colonize Mars?

Comment How can this be competitive? (Score 3, Interesting) 121

2/3rds of the satellites will always be over water and have their bandwidth utterly wasted. A significant part of the rest will be over areas where almost nobody lives, or nobody can afford to pay for internet with hard currency. Meanwhile all 400m Europeans that live in the populated 5m square kilometers have to use the same 20 to 100 satellites.

Because the satellites are not geostationary they'll need to use omnidirectional antennae which puts some hard limits on bandwidth, while a lot of people will get FTTH and 5G mobile networks in the next decade.

Iridium can get away with these shortcomings because they target the customers that doesn't care about prices. But I kind of doubt that market can support 4000 satellites

Comment The problem with this (Score 1) 314

Only 1% of the population commits crimes. In statistics you have to pay special attention to cases where probabilities are close to 0 or 1.

Here, even though 18% of the population may commit 40% of the crimes, it still only means that one of those people has a 2.2% chance (0.4% divided by 0.18) of being a criminal. If you therefore deny him a service due to fear of him being a criminal, you are still 97.8% likely to have commited an error.

Slashdot Top Deals

Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (6) Them bats is smart; they use radar.

Working...