Letter to the Editor

The Hayabusa2 lander MASCOT on the surface of asteroid (162173) Ryugu – Stereo-photogrammetric analysis of MASCam image data

¹ German Aerospace Center (DLR), Institute of Planetary Research, 12489 Berlin, Germany
e-mail: Frank.Scholten@dlr.de
² German Aerospace Center (DLR), Microgravity User Support Center (MUSC), Cologne, Germany
³ German Aerospace Center (DLR), Institute of Space Systems, Bremen, Germany
⁴ Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo, Japan
⁵ University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, Japan
⁶ Planetary Exploration Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba, Japan

Received: 23 September 2019
Accepted: 7 November 2019

Abstract

After its release and a descent and bouncing phase, the Hayabusa2 lander MASCOT came to a final rest and MASCOT’s camera MASCam acquired a set of images of the surface of Ryugu. With MASCam’s instantaneous field of view of about 1 mrad, the images provide pixel scales from 0.2 to 0.5 mm pixel⁻¹ in the foreground and up to 1 cm pixel⁻¹ for surface parts in the background. Using a stereo-photogrammetric analysis of the MASCam images taken from slightly different positions due to commanded and unintentional movements of the MASCOT lander, we were able to determine the orientation for the different measurement positions. Furthermore, we derived a 3D surface model of MASCOT’s vicinity. Although the conditions for 3D stereo processing were poor due to very small stereo angles, the derived 3D model has about 0.5 cm accuracy in the foreground at 20 cm distance and about 1.5 cm at a distance of 40–50 cm.