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NASA Says “No Chance” Small Asteroid Will Hit Earth On March 5th
universetoday ^ | 02/06/2016 | Matt Williams

Posted on 02/06/2016 10:53:52 AM PST by BenLurkin

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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

No, the NEO is part of the Solar Dynamics group at JPL. Seems to be an entirely different culture from certain other parts of NASA. These guys are real scientists. For one thing they make verifiable predictions. If they say that a moon of Saturn will occlude a seventh magnitude star at in a certain time interval, literally thousands of amateurs will be watching.

With the end of the Cold War, a lot of rice bowls got shattered. NOAA and the environmental monitoring branches of NASA glommed onto ozone layer depletion and global warming to keep as much rice bowl as they could. And an industry was born.

One of the objections that real scientist have raised about global warming hysteria is that it will hurt the reputation of science in general and atmospheric science specifically. There are a lot of charlatans in the Global Warming Industry, but very, very few in astronomy, because astronomy it is subject to verification.

Neil deGrasse Tyson is an embarrassment, but not an outright charlatan. Bill Nye is both.


42 posted on 02/07/2016 5:13:42 AM PST by Lonesome in Massachussets (Prendre cinq et rendre quatre ce n'est pas donner.)
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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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