edit on 7-11-2011 by TomServo because: (no reason given)



edit on 7-11-2011 by TomServo because: (no reason given)



edit on 7-11-2011 by TomServo because: (no reason given)



edit on 7-11-2011 by TomServo because: (no reason given)



edit on 7-11-2011 by TomServo because: (no reason given)



I am an engineer and my job involves various approaches to manipulating and analyzing data. I have this macro tool i use to interpolate and extrapolate data. So I took the distances of YU55 between Nov 4 - 11 (according to JPL, the close approach data is Nov 9 at 0.0022AU). Therefore, i get the following dataset:Date Ref App Dist.4 -5 0.03915 -4 0.03126 -3 0.02347 -2 0.01568 -1 0.00799 0 0.002210 1 0.008511 2 0.0162Then I interpolate a per hour basis. So it looks something like:Date Ref App Dist.4 -5 -0.0391-4.958333333 -0.038770833-4.916666667 -0.038441667-4.875 -0.0381125... ... ...Now think about this for a second... First of all, over a 7 day period, the trajectories of these two bodies are going to be relatively linear (straight). Therefore, the relative distance between the two will be linear as well (no corealis or angular acceleration or anything like that). Therefore, I should not see any significant disturbances in the data.Secondly, the day to day distance given by jpl is taken at a 24 hr interval. Everything in between, they interpolate (supposedly just like I did). I compared their hour by hour distance to my interpolated data. All was spot on Until I got to the 8th (day before/of close approach). I observed that their distance decayed much more slowly than mine. So I created the following data. Notice, i applied the use of negative and positive distance to account for distance before and after close approach:4 -5 -0.03915 -4 -0.03126 -3 -0.02347 -2 -0.01568 -1 -0.00799 0 0.002210 1 0.008511 2 0.0162And came up with this during the course of Nov 8th:8 -1 -0.0079-0.958333333 -0.007479167-0.916666667 -0.007058333-0.875 -0.0066375-0.833333333 -0.006216667-0.791666667 -0.005795833-0.75 -0.005375-0.708333333 -0.004954167-0.666666667 -0.004533333-0.625 -0.0041125-0.583333333 -0.003691667-0.541666667 -0.003270833-0.5 -0.00285-0.458333333 -0.002429167-0.416666667 -0.002008333-0.375 -0.0015875-0.333333333 -0.001166667-0.291666667 -0.000745833-0.25 -0.000325-0.208333333 9.58333E-05-0.166666667 0.000516667-0.125 0.0009375-0.083333333 0.001358333-0.041666667 0.0017791679 0 0.0022Which indicates that the close approach distance is actually 0.0000958333 AU at about 7pm.When I plotted this across the close approach date (9th, or day 0), I saw an odd jink (referenced above by differing distance decay), indicating that the supposed close approach distance (.0022) was further than the distance that the data would indicate IF (0, .0022) was not a 'known' point in the data.So, I took the same approach, except using this data as reference:Date Ref App Dist.4 -5 -0.03915 -4 -0.03126 -3 -0.02347 -2 -0.01568 -1 -0.007910 1 0.008511 2 0.0162Now things get interesting. According to this data, removing the supposed close approach distance which made me suspicious, the following is what the 8th looks like:8 -1 -0.0079-0.958333333 -0.007558333-0.916666667 -0.007216667-0.875 -0.006875-0.833333333 -0.006533333-0.791666667 -0.006191667-0.75 -0.00585-0.708333333 -0.005508333-0.666666667 -0.005166667-0.625 -0.004825-0.583333333 -0.004483333-0.541666667 -0.004141667-0.5 -0.0038-0.458333333 -0.003458333-0.416666667 -0.003116667-0.375 -0.002775-0.333333333 -0.002433333-0.291666667 -0.002091667-0.25 -0.00175-0.208333333 -0.001408333-0.166666667 -0.001066667-0.125 -0.000725-0.083333333 -0.000383333-0.041666667 -4.16667E-059 0 0.00030.041666667 0.0006416670.083333333 0.000983333Which indicates that the close approach distance is 0.0000416667AU = 3904 miles at about 11pm on the 8th, which is quite about closer than 200,000 miles.This might not make sense to some. All I am trying to say here is that it appears the JPL data is inconsistent.Some have asked for some sort of data representation. Here is a basic plot of the two datasets described above. One 'With' (blue) the 0.0022 point included, and the other 'Without' (red) the 0.0022 point included, substituting interpolation. I have done nothing to exaggerate how this data appears. It is what it is. In response to Phage, you can see when looking at such a narrow scope of 1 week, the data should be relatively linear. You can admit that this visual representation of the data indicates adverse manipulations. I apologize for any confusion. The point of this post is indicated in this image. It has little to do with accurate/inaccurate interpolations, but rather the accuracy and integrity of the supposed 0.0022 close approach distance.x = Days (-6 to 2)y = Distance (negative prior to close approach, positive after close approach)