Horizons has a new orbit solution which includes the three precovery
observations. The
new solution gives a nominal Close Approach distance between Mars and 2007 WD5
on January 30.49044 of 0.000140 AU and a probability of a Mars impact of 3.949%
(or 1 :
25):

Date (CT) Body CA Dist MinDist MaxDist Vrel TCA3Sg Nsigs
P_i/p
---------------------- ----- ------- ------- ------- ------ ------ ---
--- -------
A.D. 2007 Nov 01.90736 Earth .047639 .047464 .047813 8.824 0.97 600.84
.000000
A.D. 2008 Jan 30.49044 Mars .000140 .000003 .001505 12.673 432.68 .26052
.039490

Christian Kjærnet

--- In mpml@yahoogroups.com, "Jon Giorgini" <Jon.Giorgini@...> wrote:
>
> For now, one can generate a close-approach table with some numeric specifics
using
> Horizons:
>
> Date (CT) Body CA Dist MinDist MaxDist Vrel TCA3Sg Nsigs
P_i/p
> ----------------- ----- ------- ------- ------- ------ ------ ------ -
------
> 2007 Nov 01.90660 Earth .047704 .047200 .048211 8.836 14.61 591.03
.000000
> 2008 Jan 30.38261 Mars .000346 .000000 .004501 12.601 1315.6 .23291
.013428
>
> Date (CT) =
> Nominal close-approach date (Coordinate Time).
>
> Body =
> Name or abbreviation of the planetary body or major asteroid being
> closely approached by the selected small-body.
>
> CA Dist =
> Nominal geometric close-approach distance at the close-approach time,
> uncorrected for light travel time. Units: AU
>
> MinDist =
> Minimum close-approach distance possible (formal 3 standard-deviations
> with linearized covariance mapping). Units: AU
>
> MaxDist =
> Maximum close-approach distance possible (formal 3 standard-deviations
> with linearized covariance mapping). Units: AU
>
> Vrel =
> Relative velocity of the object and the body it is approaching at the
> nominal time of close-approach. Units: KM/S
>
> TCA3Sg =
> Close-approach-time 3-standard deviation uncertainty. Units: MINUTES
>
> Nsigs =
> The number of standard deviations (sigmas) required for the error ellipse
> to intersect the body being closely approached. Units: STANDARD DEVIATIONS
>
> P_i/p =
> Linearized probability of the object impacting the body.
>
>
> --- In mpml@yahoogroups.com, "Glenn Wallace" <glenn@> wrote:
> >
> > I thought I missed it, but searched mpml posts and couldn't find any mention
(or of
> 7W83BDA).
> >
> > http://www.msnbc.msn.com/id/22350742/
> >
> > (note: Associated Press has the SL-9 impact year wrong, should be 1994, not
2004)
> >
> > Where can we find impact solutions? (JPL NEO page only lists potential Earth
impacts,
> correct?
> >
> > [Non-text portions of this message have been removed]
> >
>