Some observations are now coming in at the Minor Planet Center for 2012 DA14. There is some deviation from where the 2012 predictions say 2012 DA14 will be. I used the observations from Feb 6 through Feb 8 to get an estimated position and velocity for the asteroid. A simple projection along the direction of the velocity indicates that the close approach will occur in early March.
I merged the gravitational attraction of the Earth and Moon into a single body to get a better estimate of the close approach.
This is also a rough estimate but it doesn't appear that 2012 DA14 will approach as closely as predicted a year ago. My fit wasn't particularly good with the asteroid at about 600 Earth radii away. The uncertainty in angular direction is magnified by this distance to increase the uncertainty in the asteroid's position. The uncertainty in the velocity also contributes to the uncertainty in the distance of close approach. One needs to take the Earth's motion and the Sun's gravitational field into account to get a better path for the asteroid's motion. The estimated position and velocity above are given relative to the Earth's center.
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