Re: Report for peer review
Thomas said:
I've been looking at your analysis. Your parallax calculations are incorrect because they take no account of the erratic route or azimuth.
Actually, I noted this problem as well but felt that the changing direction was not too serious a problem. Your analysis shows that this might not be a good assumption. However, your parallax calculations are not that accurate either in that you assume that the angles are correctly calculated. You are dealing with a latitude/longitude update every 5 seconds which have a minimum resolution of 0.01 minute of arc. This only resolves down to about 60 feet position. When dealing with long distances, this is not a serious problem. However, when you are calculating angles for five seconds of travel, which can introduce an angle error of near +/- 1 degree! For instance at time 17:03:36, the angle for this time change is
delta long = 0.29 minutes
delta lat = 0.04 minutes
This computes to an angle of 82.15 degrees.
If the actual position were 0.291 and 0.039 (which would indicate .029 and .04), the new angle would be 82.36 degrees. If one were take the extreme of 0.294 and 0.036, the angle becomes 83.02 (almost a degree off).
This might explain why the flight path is "erratic" in that the resolution is not great enough to provide a "smooth" flight path. It is probable (and likely) that there were changes in direction but with the data available, it is hard to ascertain what those changes exactly were.
Thomas said:
I can prove that the twins are more 400 km away using that method, and I'm pretty sure you wouldn't like that. .
I am glad you know how I feel about things. I always wondered why those who want these discussions to be scientific in nature resort to personal comments such as these. Earlier you went on a rant that amounted to a personal attack because I pointed out some erroneous statements you made. It seems you still bear some form of grudge over that. Doesn't this "derail the scientific process"? Let's move on.
Thomas said:
In fact I can prove they're not stationary as well.
You have to take account of the azimuth update issue + the erratic route and adjust the azimuth accordingly. You can see an example of this in my report.
Which has disappeared. I was on vacation and only caught a glance at the work when it appeared. The work is good and I await the update. There are a few issues I noted from the brief glance I saw:
1. You seemed to use only a 3 degree elevation for the "twins" in your calculations. However, at times 17:03:35-17:03:43, this value is 2 degrees and becomes 2 degrees again between times 17:03:54-17:03:59. It even dips to 1 degree after this. The table should reflect these values and not just show the one reading of 3 degrees.
2. In your anamoly of how the two set of groups are not the same, I think you need to reevaluate. The first map you made used the Narrow and the second map used the Narrow X2 FOV. This would change the scale of the map and "cut off" some of the objects that are outside the FOV. I also suggest you examine how the separation between the trios changes during the time period of 17:06:43-17:07:21. The separation between the two is increasing. This means earlier in time, these two groups are going to appear closer together and give a different appearance.
3. I am curious as to why you only made one distance calculation. It is only one data point and it would be interesting to see how well this stands up to calculations on the "twins" from other data points. I would not be suprised the distance of the "twins" was closer than the others considering the apparent size appears much larger.
I am also interested to see what you calculations for the group at times 17:06-17:07 appear to be. Is there a reason you took only one data point and declared that this is the apparent distance?
Thomas said:
I also have to wonder if your lat/lon readings for your parallax calculations are correct, because I've only seen you state four of these in your analysis, where only one is correct, the remaining three appear to be misreadings.
Guilty as charged. That is what I get for trying to look at some blurry images late at night and not double checking the next day. The errors did not introduce a significant change but I also found other problems with the distance traveled since the position updates every five seconds. Even with these errors, it did not throw off my calculations too much but you seemed to have demonstrated they were not accurate either.