Lutetia flyby navigation campaign up to 27 May 2010
This plot shows the situation in the target plane for Rosetta's flyby of asteroid Lutetia on 10 July 2010. The target plane is a planar coordinate system centred on the asteroid and is used for targeting during this close flyby. The target relative position of Rosetta for the flyby is marked in green and is 3160 km from asteroid Lutetia (at the origin of the plot).
The ellipses indicate 3-sigma error circles around Rosetta's predicted position (black cross) relative to asteroid Lutetia during the flyby. This prediction is based on all radiometric data up to and including 27 May 2010. For the orbit determination of asteroid Lutetia 1630 pairs of ground-based astrometric measurements, obtained over the period from 6 April 1866 up to 4 April 2010, were used. Since this end date, 10 more pairs have been obtained but their inclusion has little influence on the orbit.
The optical navigation campaign with Rosetta's on-board cameras started on 31 May, so data from those observations are not yet included in this orbit solution.
As it stands, the predicted location of Rosetta in the target plane lies 408 km from the target. If there would be no future trajectory correction manoeuvres the predicted flyby miss-distance would be 2761 km.
The predicted time of closest approach is 15:44:59.02 UTC on 10 July. The formal 3-sigma uncertainties associated with this time are 1.58 seconds due to the spacecraft orbit uncertainty and 6.30 seconds due to the asteroid orbit uncertainty. The overall uncertainty, due to both, is 6.50 seconds.
See the related image in the right-hand menu for a close up on the target region of this plot.