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Comment Re:Lets simplify this... (Score 1) 150

Difference of opinions here I guess but the definition I offered clarifies that the object to be considered a planet in any sort of clustered central orbiting system, has to be the most prominent body in that orbit. That would make Pluto the planet, and Charon the moon. Charon is about half the size of Pluto, so there is a significant difference on the gravitational influence of each celestial body as well.

The Earths moon is roughly a quarter size of our planet and in many respects, we share similarities to the Pluto-Charon system. I would argue that the Earth-Moon system is also a binary system too. However, the most prominent body of influence should retain the most prominent hierarchical name. Hence, the Earth is a planet, Luna is a moon, Pluto is a planet, and Charon is a moon.

Yeah I understand what you mean. And I understand that Charon kinda feel like a moon. But what if both (Charon and Pluto) were about the same size? You'll say that the one slightly bigger is the planet and the one slightly smaller the moon?

In my mind, for a Moon to be considered a "Moon", it have to be greatly smaller than it's planet. That's why I love to use the centre of orbit (or Barycenter) as a reference. If a "planet" is massive enough so it's clearly the "Master" of it's own system, then the barycenter will be inside itself.

Comment Re:Lets simplify this... (Score 1) 150

A planet is any object in orbit around a star, of sufficient mass to reach hydrostatic equilibrium, has not reached critical mass to achieve stellar fusion, and is the most prominent body in its orbit and neighborhood. That definition is going to add a few more planets but not many.

The suggested definition from TFA is just as terribly obtuse as the 2006 definition. Even worse is the suggestion to change the word 'planet' to become an all encompassing term that now also means most smaller bodies as well (but not all). It makes things unnecessarily confusing. This just seems tantamount to two-year-old logic where one word now means everything.

And look, my suggested definition expands.

A moon is any object in orbit around a planet, of sufficient mass to reach hydrostatic equilibrium, and is the most prominent body in its orbit and neighborhood.

A moonroid (haha maybe?) is any object in orbit around a planet, has not reached critical mass to achieve hydrostatic equilibrium, and is shares its orbit and neighborhood with other objects of similar mass.

An asteroid is any object in orbit around a star, has not reached critical mass to achieve hydrostatic equilibrium, and is shares its orbit and neighborhood with other objects of similar mass.

And so on. The hydrostatic equilibrium is critical to defining celestial bodies but it shouldn't be the only requirement to define a planet.

Hmm mostly how I see it but it fail to address binary system like Pluto–Charon.

In my mind, Charon shouldn't be considered a satellite to Pluto since the centre of orbit is outside of Pluto. Neither are "Moon", both are "Planet".

As for how to separate asteroid to "Planet", hydrostatic equilibrium is a clear win. But in my mind planet shoudl be separated in 3 group :

- Asteroid : No hydrostatic equilibrium (No rounded shape)
- Dwarf Planet : No Atmosphere (rounded shape)
- Planet : Atmosphere
- Gas Giant : Atmosphere thicker than solid core

As for satellite, exactly the same definition as planet except replace "Planet" by "Moon". So "Dwarf Moon", "Moon" and something along the line of "Gas Giant Moon".

Comment Re:oblig xkcd (Score 5, Insightful) 319

Nice find!

But in the end, it's all relate to this : The earth is a globe, and there's no way to represent is on a 2D map without :
1-Tearing the map appart
2-Stretching the map

Personally, I prefer the 3rd option : "Put more globe in your school" like this one :

Now that is awesome.

Comment Re:Rifle Bullet? No? (Score 1) 318

I'm actually impressed that the missile is sensitive enough to get triggered by hitting a drone. I would have thought the drone would just bounce right off.

I don't think modern ballistic missile got a hammer detonator at the end. I'm pretty sure there's a bunch of tech to make it automatically explode when it reach it's target.

Comment Re:Counting water (Score 1) 331

It takes about 2,500 gallons of water to produce just a pound of beef

Am I the only reminded of Azimov's The Martian Way? I mean the part, where an Earth's politician is explaining to electorate, how much water (used as reaction mass) it takes for a spaceship to get into space. The book's main characters observe, that most of the water so used falls right back onto the planet. But at least, in that novel some amount of water, however minuscule compared to Earth's vast oceans, does leave...

Well, in case of meat production — or indeed any other Earth-bound activity — no water is lost. Zero. Nada. So, what is the quoted statement supposed to mean?


I remember a dispute when a passerby yelled at my neighbour because he was "wasting" water on his lawn (I live in Canada so no shortage of water here). I've walked to him and ask him where did he thought the water was coming from. After he told be the water came from the ground, it was funny to see his face when I then asked : "But isn't he sending the water back to the reservoir?".

Using "2,500 gallons of water" is false science and I'm starting to be pissed of to all that pseudo-science. If you're an environmentalist and you want to do some real science, It's not 2,500 gallons of water that want to know, you want to know the quantity of pollution created for each pound of meat. That mean :

- The energy needed to clean/pump this water + the carbon footprint of that energy.
- The energy needed for all the process of the meat (The cow itself, the grain of it's food, the meat processing) + the carbon footprint of that energy.
- The quantity of waste/pollution created by the cow itself (Methane/piss/shit) and the whole infrastructure.
- The quantity pollution/energy to build the whole infrastructure, each one divided by each pound of meat created during it's lifetime.

I may be forgetting a thing or two.

Comment Re:Rifle Bullet? No? (Score 1) 318

I mean, we're talking consumer drone so we're talking what? ~500 feet (~150m) and 100 mph? (~160kph)

Why don't they simply shoot at it with their rifle?

Who said it was flying that low?

They said it was a 200$ drone so I've done a quick search of the range and speed of drone at that price range. But yeah I may be completely wrong.

Comment Re:Rifle Bullet? No? (Score 1) 318

Ever gone skeet shooting? Not as easy as it looks.

Well if there's one guy shooting, then sure. But what if dozens guys shoot 100-200 round per minutes, that should do it.

On top of that bullets have a higher chance of killing someone on the ground vs a missile used as an intercept device. Someone can still be killed in either case though,

Well, we're talking about a War environment. I'm surprised there's any consideration about this.

one of the reasons that lasers to shoot them down are being pushed. The other is lasers would be far cheaper and have a higher hit:miss ratio.

Unless there's a laser with every squad, I doubt it'll be a solution (but then again, is there a patriot missile with every squad?).

Submission + - Physicist declassifies rescued nuclear test films (

Eloking writes: The U.S. conducted 210 atmospheric nuclear tests between 1945 and 1962, with multiple cameras capturing each event at around 2,400 frames per second. But in the decades since, around 10,000 of these films sat idle, scattered across the country in high-security vaults. Not only were they gathering dust, the film material itself was slowly decomposing, bringing the data they contained to the brink of being lost forever.

For the past five years, Lawrence Livermore National Laboratory (LLNL) weapon physicist Greg Spriggs and a crack team of film experts, archivists and software developers have been on a mission to hunt down, scan, reanalyze and declassify these decomposing films. The goals are to preserve the films' content before it's lost forever, and provide better data to the post-testing-era scientists who use computer codes to help certify that the aging U.S. nuclear deterrent remains safe, secure and effective. To date, the team has located around 6,500 of the estimated 10,000 films created during atmospheric testing. Around 4,200 films have been scanned, 400 to 500 have been reanalyzed and around 750 have been declassified. An initial set of these declassified films — tests conducted by LLNL — were published today in an LLNL YouTube playlist (link is external).

Comment Re:Unplug it first (Score 1) 407

Yes, but this was from an adjacent work station. Equivalent to unplugging your circular saw in the garage, only to be attacked by the refrigerator in the next room.

If that's the case, then it's a design failure and the engineer that signed it should be procecuted.

If you have a risk to be attacked by the circular saw and the fridge while you're in the garage, then opening the safety circuit of the garage should disable both the fridge and the circular saw.

And if the engineer did it because he was pressured because disabling the fridge in this case will affect the production, then it's even worst since the engineer willingly bypassed a safety measures.

Comment Re:Come on, not that "Terminator" BS again... (Score 1) 407

In my mind, industrial robot are still the most dangerous piece of hardware you'll ever work with, period.

I programmed welding robots for a few years in the 90's, and I agree. Close calls are common. I once got very close to breaking a coworker's arm with a robot, except that I released the deadman switch in time.

Do you want to hear something even scarier? Robot compagnie like ABB are actually working to make their robot appear less dangerous :

"We want to lower the fear of robot because it affects our sales". Can you freaking believe it? If you got an operator working with a robot, you have to make it clear that if he doesn't respect the safety procedure or the robot speed/strength, he "will" endanger himself. Robot "are" dangerous.

What it'll be next? Dress him as a Teddy Bear so children will want to hug him?

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