27 September 2018
Images of Ryugu photographed from BOX-B.
Hayabusa2 usually stays at the home position, about 20 km from Ryugu. The direction of the spacecraft is also fixed as the home position for Hayabusa2 is situated on the line connecting Ryugu and the Earth. During this exploration period, the Earth and Sun could be seen in almost the same direction from view point of Ryugu. That meant that if the spacecraft were to stay at the home position, Ryugu would appear similar to an almost full moon. This is convenient as almost all of Ryugu is illuminated, but it is important to observe the asteroid not only from the front but also from diagonal directions. To achieve these different viewing angles, we initiated the BOX-B operation.
Image of Ryugu towards the asteroid’s south pole. Photograph taken with the Optical Navigation Camera Telescopic (ONC-T) on August 24, 2018 at around 17:00 JST. The image was captured from a position of around +y = 9 km. The distance to Ryugu was about 22 km.