From February 20 to 22, we conducted the touchdown operation (TD1-L08E1) of Hayabusa2 on the surface of asteroid Ryugu. Figure 1 shows an image taken with the Optical Navigation Camera – Wide angle (ONC-W1) during the spacecraft ascent after touchdown.
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Figure 1 was captured roughly 1 minute after touchdown at an estimated altitude of about 25m (error is a few meter). The color of the region beneath the spacecraft’s shadow differs from the surroundings and has been discolored by the touchdown. At the moment, the reason for the discoloration is unknown but it may be due to the grit that was blown upwards by the spacecraft thrusters or bullet (projectile).
Figure 2 shows the same region as Figure 1 overlapped with the planned touchdown site. Since the touchdown site sits at the center of the discolored area, we believe that it was possible to touchdown at the expected place. However, an accurate touchdown point will be examined during a more detailed analysis in the future. Also shown in Figure 2 is the white target marker, which is shining in the reflected sunlight.
For comparison, Figure 3 shows the previously captured image of the touchdown site. Figure 4 shows this same image but without any markings. Since this image was taken before dropping the target marker, the target marker is not visible in this picture. As you can see from Figures 3 and 4, there was no discolored area on the asteroid surface around the touchdown point.
※ Please use the displayed credit when reproducing these images. In the case where an abbreviated form is necessary, please write "JAXA, University of Tokyo & collaborators".
Correction: Miss type of the operation name has been corrected. TD1-L8E1 --> TD1-L08E1. (2019-07-28)