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To: Darksheare
No, orbits can be calculated by anyone who knows the math behind it.

Is that why NASA is having trouble calculating the orbit of this one?

40 posted on 02/06/2016 4:13:43 PM PST by PAR35
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To: PAR35

As number of conservations increase, the accuracy of the calculations increases.
Recall the hype over asteroid Apophis and the supposed 2029 impact?
After more observation, it was found to not be in the cards.
Asteroids, being small, dark, and often difficult to view with optical telescopes, require careful study.
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2013TX68;cad=1

The orbit, as currently known from three days of observation, could be as far out as one and a half lunar distance, or not.
Now, the uncertainty will initially increase with more observation before decreasing.
That is normal, and much of the reason for the Apophis panic.
https://en.m.wikipedia.org/wiki/99942_Apophis


41 posted on 02/06/2016 4:25:44 PM PST by Darksheare (Those who support liberal "Republicans" summarily support every action by same.)
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To: PAR35

NASA is having no problem calculating the orbit of this one. They’ll calculate anything you want. Every scientific observation comes with error bars, and so does every prediction. 2013 TX68 was observed for three days in October, 2013. Small errors in observations in 2013 will propagate to large errors in position in 2016. If you to http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2013TX68;cad=1;old=0;orb=0;cov=1;log=0#elem you can see the orbital elements and their uncertainty. If you click “Show Covariance” you get the whole covariance matrix at epoch. The mapping of orbital elements covariance at epoch to the future is highly non-linear (and to be honest, non-gaussian). Again, if you go that page, you will see on the bottom predictions about closest approach. The time uncertainty in closest approach is more than two days.

You might find the story of discovery of Ceres, and the application of the method of least squares enlightening.


43 posted on 02/07/2016 5:32:24 AM PST by Lonesome in Massachussets (Prendre cinq et rendre quatre ce n'est pas donner.)
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