Acccording to the article, if this 40 Meter, 71,000 Ton asteroid hit earth it would release the energy of 1.1 million tons of TNT.
Lets change the units...
1.1 Million Tons of TNT == 1.1 Megatons
The governments capable of getting to this thing have weapons WELL in excess of that strength on hand. They don't even have to spend hundreds of Millions of Dollars to get to the asteroid, move it (also probably with a nuke) and target it.
Mercury is significantly denser than Mars. Therefore while it IS less massive over all, it has a steeper gravity well and will cause a greater effective clearing.
However you are also forgetting the definition of neighborhood (which I only found after my original post) which is the same average distance from the primary and an orbit that is not more than an order of magnitude difference in elliptical shape (it is beyond me to characterize this further, if you want more information go to peer-reviewed journals).
THEREFORE, there is actually VERY little mass in Pluto's orbit however Pluto has not been able to clear it. Also remember that clearing doesn't necessarily mean "get rid of" but it does mean "control" by capturing as a satellite, capturing in a Lagrange point OR coercing into a synchronous orbit. If you look at Earth's orbit you will see that most of the time Venus, Mars and Mercury are closer to most of the area of the orbit than the Earth is yet the Earth still cleared out the space.
However I also saw something else while doing research for this response. This is all posited on Neptune NOT being there. Pluto is actually in orbital resonance with Neptune (3:2 I believe) therefore Pluto is under Neptune's control (another reason not to call it a planet). Since Neptune is a few times large than any terrestrial world, Mercury - Mars would also be captured like Pluto if placed in the identical orbit. Jupiter on up would even clear out Neptune. If placed in a similar but slightly different orbit then all planets should clear out the orbit.
We seem to've set up a definition that pretty much puts a maximum distance from the primary for a planet. Interesting. Not really a very meaningful definition, but interesting. You are correct, there DOES seem to be a maximum distance that a planet can form from it's primary...however we haven't declared that by fiat, rather nature seems to have made planets very unlikley as you go farther out....If you think about it, that makes perfect sense.
Actually, Jupiter would have cleared the orbit...as would Mercury, Venus, Earth, Saturn, Uranus and Neptune. Mars, the weakest, is questionable but still probably would have. The difference between planets and non-planets is THAT striking. Reading through some of the other posts on Slashdot I found a link to a calculation for clearing the neighborhood.
This definition while on the face of it seems arbitrary really is very precise and DOES describe a major difference between heavenly bodies.
But based on what I have read, the concept of neighborhood is based off of how much influence the body in question has on everything else in the same (or very similar) orbits.
Therefore since Cruinthe is orbitally locked with the Earth, the Earth has "cleared" it's orbit of everything random. (Of course there are random asteroids, comets etc that cross the orbit but aren't considered part of the neighborhood).
As far as pluto goes, it's orbit is extremly messy. If you look at all the planets (under the current deffinition) and how much mass is in the same orbit, Mars has the least influence. But even so, it has about 5100 times as much mass as the rest of the orbit combined. After Mars, Ceres is actually the closest to having cleared it's neighborhood at 0.2% of the total mass in it's orbit. Pluto is at 0.02% of the mass in it's orbit.
Pluto's orbit is littered with Kupier belt objects which it has no real control over.
Actually, size doesn't directly have anyhting to do with being designated a planet.
The official deffinition of a planet is:
The IAU therefore resolves that planets and other bodies in our Solar System, except satellites, be defined into three distinct categories in the following way: (1) A "planet" is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.
(2) A "dwarf planet" is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape2, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.
(3) All other objects3 except satellites orbiting the Sun shall be referred to collectively as "Small Solar System Bodies".
Footnotes:
1 The eight planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. 2 An IAU process will be established to assign borderline objects into either "dwarf planet" and other categories. 3 These currently include most of the Solar System asteroids, most Trans-Neptunian Objects (TNOs), comets, and other small bodies.
While a body of insufficient size will not "overcome rigids body forces" or have "cleared the neighbourhood around its orbit" the deffinition doesn't state that it must be at least 2000 km in diameter (which is arbitrary and was a running contender for the deffinition of planet). Infact you could have a very dense but small object (smaller than pluto) meet the deffinition of planet and a very defuse but large object (larger than the earth) NOT meet the deffinition. While size and mass are important, they are not what define a planet.
Since pluto hasn't cleared it's local neighborhood, it is not a planet. In addition, hundreds of pluto sized object HAVE been found in the oort cloud and Kupier Belt. However when a similar object was found orbiting inside Neuptune (Eris I beleive) it only accelerated the redeffinition of planet that was already underway.
This deffinition is actually pretty reasonable based on what types of objects dominate a solar system (excluding the sun) and how they are formed. If you look at the history of where this new deffinition came from you will find that the "devolved" scientists almost made an exception for Pluto but in the end decided to
look(ing) at the evidence and following it to where it leads
I say as soon as you discover a thousand earth sized objects orbiting the sun we can CERTAINLY talk about reclasifying the Earth or redefining planet.
HOWEVER...all the theories suggest that an earth sized object will be EXTREMLY unlikley in the Kupier belt or farther out UNLESS it was a loose planet that the sun captured.
You say we will inevitably find an earth sized object...you may be right, but finding one or two won't change anything....when you find HUNDREDS we will chat.
The biggest difference is the mass ratio's between the satellite and it's parent (this goes for planets as well as moons).
If the mass of the satellites starts to approach the mass of the parent then the system will become unstable. The Moon is by far the largest satellite as a percentage of mass anywhere in the solar system. The Pluto-Charon system beats the Earth and Moon but Pluto was downgraded from a planet. For the earth-moon system, the center of mass for the system is still inside the earth. The Pluto-Charon system the center of mass is roughly 1/3 of the way to Charon. The only reason it is stable is because it is so far away.
If the moon was significantly larger (or there was an additional moon of significant size) they system would become unstable and tend to lose satellites until it WAS stable.
Jupiter's moons are so much lighter that Jupiter has an iron gravitational grip on them. Short of a major external disruption (say getting hit by another moon) all of Jupiter's moons are staying put.
What about a microwave frequency laser? Low enough power that it doesn't cook things. But that should allow you to target devices and deliver a much higher efficiency.
not necessarily, you could construct the receiver to rotate a few degrees, maybe even 10-15 degrees in any direction wouldn't be unreasonable. Then you have a telescope with similar ranges of other large systems.
Remember that all the projections on GLOBABL warming predict that seasons will be more extreme and some areas will get significantly colder. Even if the GLOBAL temperature raises, Alberta may get much colder.
30 meters out of 2+ MILES depth over 70+% of the oceans surface. You have to remember how much water is out there. 30 meters amounts to less than.1% expansion.
Current projections are 50-100 years at CURRENT CO2 levels.
Now as far as spelling tips, I would apply the same filter as I ALWAYS apply to slashdot. "No fact on slashdot is confirmed...but it does provide pointers to get confirmed data."
Don't beleive me because I typed it. But using the info I provided you can look this up easily enough on your own.
The only question is, do YOU want to be intelectually curious OR do YOU want to decide you know everything and soly depend on your "bull shit" filter?
If the average temperature goes up it will melt some of the northern latitudes however it will also trigger an advance in deserts in the tropical region.
If the temperature changes much that the average rainfall (which is strongly dependent on temperature) will also change. You will have greater extremes more droughts followed by floods. This will strain our current ability to manage water (dams and the like). It will lead water shortages
The current ocean currents shift heat around in a predictable manner and changing the overall temperature will weaken the flows. For instance the Atlantic current in my example brings warm water directly to orthern Europe making it more like new england rather than Nova Scotia or Northern Siberia (which is on the same latitude). At the same time it delivers cold water to the caribean making that are more temperate. With the fresh water glaciers (and all glaciers are essentially fresh water) starting to melt, they are dumping lots of fresh water into the top part of this atlantic current disrupting the flow (this is already measured)
The reason we haven't seen as much temperature increase as people originally expected is because the oceans are absorbing the heat. When things get warmer they expand. Current projects have the oceans rising about 30 meters. This will essentially wipe Florida off the map. Plus most of our favorite cities are near the ocean. Say good bye to NY, DC, San Fran, LA, New Orleans (already below sea level) etc. This is all assuming the glacier DON"T melt, which will add another 5-10 meters. We will lose significant portions of the arable land if the temperture rises much.
As far as the legitimecy, about two years ago we eliminated all reasonable explinations for the global rise in temperature EXCEPT human influence. It has been a long time since the temperature change could be considered a random fluctuation.
Globabl warming IS real and it IS our fault. The only question that remains is will the remaining environmental predictions come true?
Essentially, the reason you hear so much negativity is that there is actually very little positive about it.
#1 it is unequally balanced..the temp changes more at the poles where the ecosystem is more sensitive to temperature. Therefore a small global change will mean dramatic changes in isolated areas.
#2 if you look through history, the average GLOBAL temperature over a one year period has typically hovered around 0 deg C for most of history. I hear that is an important temperature for something..... Anytime the temperature strays from freezing dramatic changes happen to the global environment.
#3 Consistency. So much of our modern society is based an the extremly mild conditions the earth has experienced over the last 20,000 years. Most of Europe is inhabitable ONLY because of the gulf stream and atlantic currents. Agriculture is ONLY possible because the temperature has been consistant year to year. We are in a sweet spot environmentally that is very unusual in earths history. screwing with the temperature is not going to help.
Slashdot Mirror
If this asteroid hits the earth it will release about 1.1 million tons of TNT worth of energy.
Put it another way, it is equivalent to a 1.1 Megaton Nuke (with little or no radioactivity)
I believe minimum safe distance for a megaton nuke (WITH radiation) is 20 kilometers...so 20 miles is perfect
Acccording to the article, if this 40 Meter, 71,000 Ton asteroid hit earth it would release the energy of 1.1 million tons of TNT.
Lets change the units...
1.1 Million Tons of TNT == 1.1 Megatons
The governments capable of getting to this thing have weapons WELL in excess of that strength on hand. They don't even have to spend hundreds of Millions of Dollars to get to the asteroid, move it (also probably with a nuke) and target it.
Well of COURSE you can't create energy from cracking water! You will NEVER be able to do that.
However, electrolysis is nice and easy and solar cells are often used in space....
Think BEFORE you type.
Mercury is significantly denser than Mars. Therefore while it IS less massive over all, it has a steeper gravity well and will cause a greater effective clearing.
However you are also forgetting the definition of neighborhood (which I only found after my original post) which is the same average distance from the primary and an orbit that is not more than an order of magnitude difference in elliptical shape (it is beyond me to characterize this further, if you want more information go to peer-reviewed journals).
THEREFORE, there is actually VERY little mass in Pluto's orbit however Pluto has not been able to clear it. Also remember that clearing doesn't necessarily mean "get rid of" but it does mean "control" by capturing as a satellite, capturing in a Lagrange point OR coercing into a synchronous orbit. If you look at Earth's orbit you will see that most of the time Venus, Mars and Mercury are closer to most of the area of the orbit than the Earth is yet the Earth still cleared out the space.
However I also saw something else while doing research for this response. This is all posited on Neptune NOT being there. Pluto is actually in orbital resonance with Neptune (3:2 I believe) therefore Pluto is under Neptune's control (another reason not to call it a planet). Since Neptune is a few times large than any terrestrial world, Mercury - Mars would also be captured like Pluto if placed in the identical orbit. Jupiter on up would even clear out Neptune. If placed in a similar but slightly different orbit then all planets should clear out the orbit.
Actually, Jupiter would have cleared the orbit...as would Mercury, Venus, Earth, Saturn, Uranus and Neptune. Mars, the weakest, is questionable but still probably would have. The difference between planets and non-planets is THAT striking. Reading through some of the other posts on Slashdot I found a link to a calculation for clearing the neighborhood.
This definition while on the face of it seems arbitrary really is very precise and DOES describe a major difference between heavenly bodies.
Now IAMAA (I am not an Astronomer).
But based on what I have read, the concept of neighborhood is based off of how much influence the body in question has on everything else in the same (or very similar) orbits.
Therefore since Cruinthe is orbitally locked with the Earth, the Earth has "cleared" it's orbit of everything random. (Of course there are random asteroids, comets etc that cross the orbit but aren't considered part of the neighborhood).
As far as pluto goes, it's orbit is extremly messy. If you look at all the planets (under the current deffinition) and how much mass is in the same orbit, Mars has the least influence. But even so, it has about 5100 times as much mass as the rest of the orbit combined. After Mars, Ceres is actually the closest to having cleared it's neighborhood at 0.2% of the total mass in it's orbit. Pluto is at 0.02% of the mass in it's orbit.
Pluto's orbit is littered with Kupier belt objects which it has no real control over.
The official deffinition of a planet is:
The IAU therefore resolves that planets and other bodies in our Solar System, except satellites, be defined into three distinct categories in the following way:
(1) A "planet" is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.
(2) A "dwarf planet" is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape2, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.
(3) All other objects3 except satellites orbiting the Sun shall be referred to collectively as "Small Solar System Bodies".
Footnotes:
1 The eight planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
2 An IAU process will be established to assign borderline objects into either "dwarf planet" and other categories.
3 These currently include most of the Solar System asteroids, most Trans-Neptunian Objects (TNOs), comets, and other small bodies.
While a body of insufficient size will not "overcome rigids body forces" or have "cleared the neighbourhood around its orbit" the deffinition doesn't state that it must be at least 2000 km in diameter (which is arbitrary and was a running contender for the deffinition of planet). Infact you could have a very dense but small object (smaller than pluto) meet the deffinition of planet and a very defuse but large object (larger than the earth) NOT meet the deffinition. While size and mass are important, they are not what define a planet.
Since pluto hasn't cleared it's local neighborhood, it is not a planet. In addition, hundreds of pluto sized object HAVE been found in the oort cloud and Kupier Belt. However when a similar object was found orbiting inside Neuptune (Eris I beleive) it only accelerated the redeffinition of planet that was already underway.
This deffinition is actually pretty reasonable based on what types of objects dominate a solar system (excluding the sun) and how they are formed. If you look at the history of where this new deffinition came from you will find that the "devolved" scientists almost made an exception for Pluto but in the end decided to look(ing) at the evidence and following it to where it leads
I say as soon as you discover a thousand earth sized objects orbiting the sun we can CERTAINLY talk about reclasifying the Earth or redefining planet.
HOWEVER...all the theories suggest that an earth sized object will be EXTREMLY unlikley in the Kupier belt or farther out UNLESS it was a loose planet that the sun captured.
You say we will inevitably find an earth sized object...you may be right, but finding one or two won't change anything....when you find HUNDREDS we will chat.
The biggest difference is the mass ratio's between the satellite and it's parent (this goes for planets as well as moons).
If the mass of the satellites starts to approach the mass of the parent then the system will become unstable. The Moon is by far the largest satellite as a percentage of mass anywhere in the solar system. The Pluto-Charon system beats the Earth and Moon but Pluto was downgraded from a planet. For the earth-moon system, the center of mass for the system is still inside the earth. The Pluto-Charon system the center of mass is roughly 1/3 of the way to Charon. The only reason it is stable is because it is so far away.
If the moon was significantly larger (or there was an additional moon of significant size) they system would become unstable and tend to lose satellites until it WAS stable.
Jupiter's moons are so much lighter that Jupiter has an iron gravitational grip on them. Short of a major external disruption (say getting hit by another moon) all of Jupiter's moons are staying put.
What about a microwave frequency laser? Low enough power that it doesn't cook things. But that should allow you to target devices and deliver a much higher efficiency.
Any thoughts?
not necessarily, you could construct the receiver to rotate a few degrees, maybe even 10-15 degrees in any direction wouldn't be unreasonable. Then you have a telescope with similar ranges of other large systems.
perhaps the fact that the tampering would be discovered the next time someone came to collect the data...
I was under the impression that neutrinos, anti or otherwise are extremly difficult to detect...
Does anyone have a link that suggests anything different?
IT occurs to me that is the focal length is THAT long we could put these very large systems in space and have a smaller GROUND based detector.
Simply put the thing in GEO orbit and point it at a receiving station. This will dramatically increase the "lense" size.
Of course you will get some interference from the atmosphere but this can be activly compensated.
I guess you won't know until you look.
Remember that all the projections on GLOBABL warming predict that seasons will be more extreme and some areas will get significantly colder. Even if the GLOBAL temperature raises, Alberta may get much colder.
30 meters out of 2+ MILES depth over 70+% of the oceans surface. You have to remember how much water is out there. 30 meters amounts to less than .1% expansion.
Current projections are 50-100 years at CURRENT CO2 levels.
Now as far as spelling tips, I would apply the same filter as I ALWAYS apply to slashdot. "No fact on slashdot is confirmed...but it does provide pointers to get confirmed data."
Don't beleive me because I typed it. But using the info I provided you can look this up easily enough on your own.
The only question is, do YOU want to be intelectually curious OR do YOU want to decide you know everything and soly depend on your "bull shit" filter?
No, it's NOT true for most oh time...but it IS true for the entier length of human civilization.
True we may not go extinct but I still kinda like civilization.
It is a "Bad" thing for several reasons.
If the average temperature goes up it will melt some of the northern latitudes however it will also trigger an advance in deserts in the tropical region.
If the temperature changes much that the average rainfall (which is strongly dependent on temperature) will also change. You will have greater extremes more droughts followed by floods. This will strain our current ability to manage water (dams and the like). It will lead water shortages
The current ocean currents shift heat around in a predictable manner and changing the overall temperature will weaken the flows. For instance the Atlantic current in my example brings warm water directly to orthern Europe making it more like new england rather than Nova Scotia or Northern Siberia (which is on the same latitude). At the same time it delivers cold water to the caribean making that are more temperate. With the fresh water glaciers (and all glaciers are essentially fresh water) starting to melt, they are dumping lots of fresh water into the top part of this atlantic current disrupting the flow (this is already measured)
The reason we haven't seen as much temperature increase as people originally expected is because the oceans are absorbing the heat. When things get warmer they expand. Current projects have the oceans rising about 30 meters. This will essentially wipe Florida off the map. Plus most of our favorite cities are near the ocean. Say good bye to NY, DC, San Fran, LA, New Orleans (already below sea level) etc. This is all assuming the glacier DON"T melt, which will add another 5-10 meters. We will lose significant portions of the arable land if the temperture rises much.
As far as the legitimecy, about two years ago we eliminated all reasonable explinations for the global rise in temperature EXCEPT human influence. It has been a long time since the temperature change could be considered a random fluctuation.
Globabl warming IS real and it IS our fault. The only question that remains is will the remaining environmental predictions come true?
Essentially, the reason you hear so much negativity is that there is actually very little positive about it.
Whats wrong with asparagus??
The problem with global warming is three fold....
#1 it is unequally balanced..the temp changes more at the poles where the ecosystem is more sensitive to temperature. Therefore a small global change will mean dramatic changes in isolated areas.
#2 if you look through history, the average GLOBAL temperature over a one year period has typically hovered around 0 deg C for most of history. I hear that is an important temperature for something..... Anytime the temperature strays from freezing dramatic changes happen to the global environment.
#3 Consistency. So much of our modern society is based an the extremly mild conditions the earth has experienced over the last 20,000 years. Most of Europe is inhabitable ONLY because of the gulf stream and atlantic currents. Agriculture is ONLY possible because the temperature has been consistant year to year. We are in a sweet spot environmentally that is very unusual in earths history. screwing with the temperature is not going to help.
we will actually reach that population level again.
Environmental damage here we come!
When you are charging off of an ICE you are right but with current battery systems you can achieve 90+% chrging efficiencies.
Honda is incorpoating these into thier hybrids for 2009 or 2010.
For the article I am not sure it applies...
Where is the fly-me-to-the-outer-system-to-collect-dust-and-gas tag?