Asteriod strike?
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Trollslayer was giving you the scoop, you should do what he says. The reason we don't have a good grasp on where it is going is because we do not have a good grasp of it's current velocity vector. We have a number of sightings, each of which has error associated with it. When you use the sightings to determine velocity, you get a vector with error associated with it. The current (as of the writing of the article) position and velocity vectors and errors give a volume of space at a particular time the the asteroid will be in, that has a 1 in 75 chance of being coincident with the volume of space that mars is in. There is no large conspiracy by the astronomical community to keep you knowing if it will hit. There IS a large conspiracy to get people to understand the odds of it hitting. That conspiracy involves large parts of the astronomy community, big chunks of the media, including the code project, trollslayer and I. Clearly, our conspiracy is failing
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I think we have discovered the problem here. They didn't account for the gravity generated by the mass of your far superior brain. That must be effecting the path of the thing. Actually you are correct they know all those things but what they don't know is the mass of the object itself. Gravity is a two way street and the gravity of an object is based on it's mass. They actually do "weave and bob" (although not sharply of course) based on how they are effected by the gravity of other objects of around it. It's all relativity. Even light doesn't move in a straight path. It's effected by gravity as well. This is predictable but you have to understand the mass of all the objects involved.
The error in the trajectory that is caused by the error in the knowledge of the asteroids mass is negligible. The acceleration component contributed by the asteroid mass could be zero and the error in impact location would be on the order of miles, over the 45 days remaining. The real problem is location measurement error, both because it changes the possible starting point, and because it changes the velocity vector. To determine it's effects, we can use a radius of 6,300,000 meters for the earth (it is really larger), and 100 meters for the asteroid (it is less than half that). The ratio of the mass of the asteroid to the mass of the earth, as a first order approximation, is linear to the ratio of the volumes. The volume is proportional to the radius cubed, so the ratio of masses is, as well. The ratios of radii is 63,000 to 1. The ratio of volumes is 250,047,000,000,000 to 1. The gravitational attraction is proportional to the mass, so the difference is 2.50*10^14, which we can round to 1*10^14, just for ease. So 9.8 m/s^2 becomes 9.8*10^-14 m/s^2, if it were at the surface of the earth the whole time (it's not). Assuming it was adding this whole amount in the worst possible way(it's not) the whole time (45 days * 86,400 secs/day) yields a delta v of 3.81024*10^-7 meters per second. Over 45 days, assuming it was at that velocity the whole time, that would lead to a total change of location of about 1.5 meters. :omg: We would have the same error if it was 45 days between observations, and the entire positional error was 1.5 meters (same velocity error budget). The error gets bigger as the time between measurements gets smaller, and as the positional error goes up. I suspect the error is at least in the hundreds of meters, and probably in kilometers.
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http://www.msnbc.msn.com/id/22350742/[^] I wonder what kinda pictures the rover will get, cause its supposed to hit close to it.
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Ri Qen-Sin wrote:
Anyhow, so what? That doesn't exclude objects within the solar system from the laws of physics.
Why don't you try to explain this to Mr Brummer ... and to yourself, of course? :doh: Allow me to remind you of his silly "challenge" to me: "Really? You don't think the sun or Jupiter will have an effect?" :laugh:
He's right: you are full of it. Brummer was on the right track with regard to the fact that there are a lot of variables and levels of indirection that are used to watch these things. A lot of it is "probabilistic," not deterministic. As in, there are varying levels of uncertainty, not to mention error margins. With these, they can't be sure. You might want to study a little concept called chaos. In stochastic, or partly-random, systems there is always uncertainty, and small changes (like Jupiter's gravity) can have large effects throughout the system (like making it miss). You should read up on this stuff before you make any claims. Obviously, figuring it out takes supercomputers and physics/math wizes at NASA for a reason. It's not so linear, dude. This ain't a game of Asteroids. ;)
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The error in the trajectory that is caused by the error in the knowledge of the asteroids mass is negligible. The acceleration component contributed by the asteroid mass could be zero and the error in impact location would be on the order of miles, over the 45 days remaining. The real problem is location measurement error, both because it changes the possible starting point, and because it changes the velocity vector. To determine it's effects, we can use a radius of 6,300,000 meters for the earth (it is really larger), and 100 meters for the asteroid (it is less than half that). The ratio of the mass of the asteroid to the mass of the earth, as a first order approximation, is linear to the ratio of the volumes. The volume is proportional to the radius cubed, so the ratio of masses is, as well. The ratios of radii is 63,000 to 1. The ratio of volumes is 250,047,000,000,000 to 1. The gravitational attraction is proportional to the mass, so the difference is 2.50*10^14, which we can round to 1*10^14, just for ease. So 9.8 m/s^2 becomes 9.8*10^-14 m/s^2, if it were at the surface of the earth the whole time (it's not). Assuming it was adding this whole amount in the worst possible way(it's not) the whole time (45 days * 86,400 secs/day) yields a delta v of 3.81024*10^-7 meters per second. Over 45 days, assuming it was at that velocity the whole time, that would lead to a total change of location of about 1.5 meters. :omg: We would have the same error if it was 45 days between observations, and the entire positional error was 1.5 meters (same velocity error budget). The error gets bigger as the time between measurements gets smaller, and as the positional error goes up. I suspect the error is at least in the hundreds of meters, and probably in kilometers.
At least I now know whos paper I should copy next time I'm taking a test.
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He's right: you are full of it. Brummer was on the right track with regard to the fact that there are a lot of variables and levels of indirection that are used to watch these things. A lot of it is "probabilistic," not deterministic. As in, there are varying levels of uncertainty, not to mention error margins. With these, they can't be sure. You might want to study a little concept called chaos. In stochastic, or partly-random, systems there is always uncertainty, and small changes (like Jupiter's gravity) can have large effects throughout the system (like making it miss). You should read up on this stuff before you make any claims. Obviously, figuring it out takes supercomputers and physics/math wizes at NASA for a reason. It's not so linear, dude. This ain't a game of Asteroids. ;)
NimitySSJ wrote:
He's right: you are full of it.
And you intentionally stuff yourself full of "it."
NimitySSJ wrote:
You might want to study a little concept called chaos.
You might want to study a little concept called 'logic,' or another called 'reason.'
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Trollslayer was giving you the scoop, you should do what he says. The reason we don't have a good grasp on where it is going is because we do not have a good grasp of it's current velocity vector. We have a number of sightings, each of which has error associated with it. When you use the sightings to determine velocity, you get a vector with error associated with it. The current (as of the writing of the article) position and velocity vectors and errors give a volume of space at a particular time the the asteroid will be in, that has a 1 in 75 chance of being coincident with the volume of space that mars is in. There is no large conspiracy by the astronomical community to keep you knowing if it will hit. There IS a large conspiracy to get people to understand the odds of it hitting. That conspiracy involves large parts of the astronomy community, big chunks of the media, including the code project, trollslayer and I. Clearly, our conspiracy is failing
RichardM1 wrote:
Trollslayer was giving you the scoop, you should do what he says.
Trollslayer was refusing to think critically -- as are you. You both (to say nothing of the childish "responders") are refusing to think critically about what I've said (which is very little, really) or about what you yourselves are saying in "response." You (singular, dual, plural) refuse to let go of the false concept that "Science" == Truth.
RichardM1 wrote:
Clearly, our conspiracy is failing
Clearly, you people refuse to reason.
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RichardM1 wrote:
Trollslayer was giving you the scoop, you should do what he says.
Trollslayer was refusing to think critically -- as are you. You both (to say nothing of the childish "responders") are refusing to think critically about what I've said (which is very little, really) or about what you yourselves are saying in "response." You (singular, dual, plural) refuse to let go of the false concept that "Science" == Truth.
RichardM1 wrote:
Clearly, our conspiracy is failing
Clearly, you people refuse to reason.
Did you follow what I said? They don't know if it will hit for the same reason a baseball player does not hit a home run 100% of the time. Information is limited. If you don't know where the ball is going, it is hard to get the bat in the right spot to hit it.
All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
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NimitySSJ wrote:
He's right: you are full of it.
And you intentionally stuff yourself full of "it."
NimitySSJ wrote:
You might want to study a little concept called chaos.
You might want to study a little concept called 'logic,' or another called 'reason.'
In this case, don't worry about logic and reason, work on physics and statistics.
All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
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Ilíon wrote:
Think about this, will you? How can they not already know the trajectory? The asteroid wasn't discovered just today, it was discovered a month ago -- they know where it was a month ago and they know where it is today. These things don't weave and bob, there are no cross-winds to deflect the trajectory; at most, the gravity of Mars will affect the asteroid's trajectory (when it gets close to the planet) -- and, supposedly, Mars' mass and gravity is well understood.
First of all, a month, in astronomical terms, is not a very long time. Second, small asteroids do in fact weave and bob. Picture this 50-meter diameter chunk of rock moving in space at 8 miles a second - not only is it moving forward but it's also rotating. And given that these things don't have an axis and can be very irregular in shape, I would imagine that it's movement looks something like a screwball heading for home plate (if you can make the baseball connection). Heck, just earlier this year scientists discovered that sunlight, yes sunlight, impacts asteroid trajectory - the subtle warming of one side changes the rotation rate and impacts the trajectory. There are many small factors that can have big effects on trajectories. My 2 cents.
JonoUNC89 wrote:
First of all, a month, in astronomical terms, is not a very long time.
You're not even paying attention to what you yourself are saying, are you? We're not talking about the Andromeda Galaxy, we're talking about something happenning in the inner/near reaches of this solar system and observable with only a few minutes delay of real-time.
JonoUNC89 wrote:
Second, small asteroids do in fact weave and bob. Picture this 50-meter diameter chunk of rock moving in space at 8 miles a second - not only is it moving forward but it's also rotating. And given that these things don't have an axis and can be very irregular in shape, I would imagine that it's movement looks something like a screwball heading for home plate (if you can make the baseball connection).
You clearly are not even *thinking* about what you're saying.
JonoUNC89 wrote:
Heck, just earlier this year scientists discovered that sunlight, yes sunlight, impacts asteroid trajectory - the subtle warming of one side changes the rotation rate and impacts the trajectory. There are many small factors that can have big effects on trajectories.
We're not talking about a decades-long trajectory. We're talking about one month from now. ps. If "scientists" only this year discovered that sunlight can affect an asteroid's trajectory -- over a long-term, let us understand -- then they're not too good at thinking wholistically, are they? I mean, come on! The concept (and verification) of "solar wind" is not new.
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I think we have discovered the problem here. They didn't account for the gravity generated by the mass of your far superior brain. That must be effecting the path of the thing. Actually you are correct they know all those things but what they don't know is the mass of the object itself. Gravity is a two way street and the gravity of an object is based on it's mass. They actually do "weave and bob" (although not sharply of course) based on how they are effected by the gravity of other objects of around it. It's all relativity. Even light doesn't move in a straight path. It's effected by gravity as well. This is predictable but you have to understand the mass of all the objects involved.
Tad McClellan wrote:
I think we have discovered the problem here. They didn't account for the gravity generated by the mass of your far superior brain. That must be effecting the path of the thing.
That's an interesting theory. I have another ... Until quite recently, it has always been assumed that that over-sized head of yours was at least stuffed with matter (regardless of the assumed state of functionality of that matter), However, with data derived from the recent discovery that the most pure vacuum encountered to date is the space between your ears, many long-standing astronomical mysteries may at last be solvable. Perhaps even the Pioneer Anomaly.
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Did you follow what I said? They don't know if it will hit for the same reason a baseball player does not hit a home run 100% of the time. Information is limited. If you don't know where the ball is going, it is hard to get the bat in the right spot to hit it.
All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
RichardM1 wrote:
Did you follow what I said?
I can't see that you yourself are even following what you've posted. To put it another way, I can't see that you are thinking wholistically. Just consider what you've said to this "Tad McClellan" fellow in conjuction with the bilge of faulty and non-applicable analogy you're trying to employ here.
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In this case, don't worry about logic and reason, work on physics and statistics.
All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
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Regardless of the mass of any object, it doesn't go just bouncing around in space. You know, inertia and all that. ............... Also, this object is right in front of our eyes, so to speak. If our scientific "truth" can't determine the mass of something that can be observed up close and in real time, why would you trust that it can determine the mass of objects thousands or millions (or billions) of light years away?
Ilíon wrote:
Regardless of the mass of any object, it doesn't go just bouncing around in space. You know, inertia and all that.
Well, that's not quite right! More likely they do wind around in space and do not fly straight ahead! It depends most of gravity, mass and speed! The problem now ist, that nobady is able to know the exact mass of the asteroid. They may be able to see the asteroid size, but don't know much about his material and density to have sufficient data and calculate his mass! So all they have is a round estimated mass value and maybe they are able to guess an (approximate) inertia! Well, I'm sure they have done much more than just to guess, but there is nothing more that they are able to say as a probability faktor/value. PS: About logic! Do you see now the bug in your logic function? :-D
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RichardM1 wrote:
In this case, don't worry about logic and reason, work on physics and statistics.
What a wonderful demonstration of the way "Science" worshippers think (if I may misuse that last word).
Awww....you're gorgeous! :)
"We were backstage, playing Monopoly. Totally forgot there was a show, so sorry we are late." - Maynard James Keenan
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RichardM1 wrote:
Did you follow what I said?
I can't see that you yourself are even following what you've posted. To put it another way, I can't see that you are thinking wholistically. Just consider what you've said to this "Tad McClellan" fellow in conjuction with the bilge of faulty and non-applicable analogy you're trying to employ here.
Wow, I bet I could write a program that just churns out responses indistinguishable from yours. I'd call it The Ilíon Generator. I reckon you're the first human that would fail the Turing test.
"We were backstage, playing Monopoly. Totally forgot there was a show, so sorry we are late." - Maynard James Keenan
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Tad McClellan wrote:
I think we have discovered the problem here. They didn't account for the gravity generated by the mass of your far superior brain. That must be effecting the path of the thing.
That's an interesting theory. I have another ... Until quite recently, it has always been assumed that that over-sized head of yours was at least stuffed with matter (regardless of the assumed state of functionality of that matter), However, with data derived from the recent discovery that the most pure vacuum encountered to date is the space between your ears, many long-standing astronomical mysteries may at last be solvable. Perhaps even the Pioneer Anomaly.
Heeheehee! I LOVE it how you can turn a perfectly funny joke into something terribly unfunny! :rose:
"We were backstage, playing Monopoly. Totally forgot there was a show, so sorry we are late." - Maynard James Keenan
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Wow, I bet I could write a program that just churns out responses indistinguishable from yours. I'd call it The Ilíon Generator. I reckon you're the first human that would fail the Turing test.
"We were backstage, playing Monopoly. Totally forgot there was a show, so sorry we are late." - Maynard James Keenan
LOL, That was...Good. As a matter of fact,Very Good.
All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.
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Because you don't believe in science. You apparently don't believe that things always fall towards the ground.
"We were backstage, playing Monopoly. Totally forgot there was a show, so sorry we are late." - Maynard James Keenan
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JonoUNC89 wrote:
First of all, a month, in astronomical terms, is not a very long time.
You're not even paying attention to what you yourself are saying, are you? We're not talking about the Andromeda Galaxy, we're talking about something happenning in the inner/near reaches of this solar system and observable with only a few minutes delay of real-time.
JonoUNC89 wrote:
Second, small asteroids do in fact weave and bob. Picture this 50-meter diameter chunk of rock moving in space at 8 miles a second - not only is it moving forward but it's also rotating. And given that these things don't have an axis and can be very irregular in shape, I would imagine that it's movement looks something like a screwball heading for home plate (if you can make the baseball connection).
You clearly are not even *thinking* about what you're saying.
JonoUNC89 wrote:
Heck, just earlier this year scientists discovered that sunlight, yes sunlight, impacts asteroid trajectory - the subtle warming of one side changes the rotation rate and impacts the trajectory. There are many small factors that can have big effects on trajectories.
We're not talking about a decades-long trajectory. We're talking about one month from now. ps. If "scientists" only this year discovered that sunlight can affect an asteroid's trajectory -- over a long-term, let us understand -- then they're not too good at thinking wholistically, are they? I mean, come on! The concept (and verification) of "solar wind" is not new.
I wish I could marry you.
"We were backstage, playing Monopoly. Totally forgot there was a show, so sorry we are late." - Maynard James Keenan