TopicsMINERVA-II1: Successful image capture,
landing on Ryugu and hop!

On September 21, the small compact MINERVA-II1 rovers separated from the Hayabusa2 spacecraft (time of separation was 13:06 JST). The MINERVA-II1 consists of two rovers, Rover-1A and Rover-1B. We have confirmed both rovers landed on the surface of asteroid Ryugu. The two rovers are in good condition and are transmitting images and data. Analysis of this information confirmed that at least one of the rovers is moving on the asteroid surface.

MINERVA-II1 is the world’s first rover (mobile exploration robot) to land on the surface of an asteroid. This is also the first time for autonomous movement and picture capture on an asteroid surface. MINERVA-II1 is therefore “the world’s first man-made object to explore movement on an asteroid surface”. We are also delighted that the two rovers both achieved this operation at the same time.

The following is a picture sent from MINERVA-II1.

  • [open in another window] Figure 1: Image captured by Rover-1A on September 21 at around 13:08 JST. This is a color image taken immediately after separation from the spacecraft. Hayabusa2 is at the top and the surface of Ryugu is bottom. The image is blurred because the shot was taken while the rover was rotating.
    (Image credit: JAXA)

  • [open in another window] Figure 2: Image captured by Rover-1B on September 21 at around 13:07 JST. This color image was taken immediately after separation from the spacecraft. The surface of Ryugu is in the lower right. The coloured blur in the top left is due to the reflection of sunlight when the image was taken.
    (Image credit: JAXA)

  • [open in another window. (rotated image)] Figure 3: Image captured by Rover-1A on September 22 at around 11:44 JST. Color image captured while moving (during a hop) on the surface of Ryugu. The left-half of the image is the asteroid surface. The bright white region is due to sunlight.
    (Image credit: JAXA).

The MINERVA-II1 cameras can shoot in color. In Figure 1, although the image is blurred due to the rover rotating, you can clearly see the body of Hayabusa2 and the paddle of the solar cells. The solar paddle appears blue. In Figure 3, the image was taken during a hop on the surface and you can feel this dynamic movement.

Operation of MINERVA-II1 will continue from now on. We are planning to acquire more data for analysis.

Comments from Project Members

■ Tetsuo Yoshimitsu, Responsible for the Hayabusa2 Project MINERVA-II1.
Although I was disappointed with the blurred image that first came from the rover, it was good to be able to capture this shot as it was recorded by the rover as the Hayabusa2 spacecraft is shown. Moreover, with the image taken during the hop on the asteroid surface, I was able to confirm the effectiveness of this movement mechanism on the small celestial body and see the result of many years of research.

■ Takashi Kubota, Spokesperson for the Hayabusa2 Project (also responsible for the MINERVA-II1)
The good news made me so happy. From the surface of Ryugu, MINERVA-II1 sent a radio signal to the Earth via Hayabusa2 S/C. The image taken by MINERVA-II1 during a hop allowed me to relax as a dream of many years came true. I felt awed by what we had achieved in Japan. This is just a real charm of deep space exploration.

■ Yuichi Tsuda, Hayabusa2 Project Project Manager
I cannot find words to express how happy I am that we were able to realize mobile exploration on the surface of an asteroid. I am proud that Hayabusa2 was able to contribute to the creation of this technology for a new method of space exploration by surface movement on small bodies.

■ Makoto Yoshikawa, Hayabusa2 Project Mission Manager
I was so moved to see these small rovers successfully explore an asteroid surface because we could not achieve this at the time of Hayabusa, 13 years ago. I was particularly impressed with the images taken from close range on the asteroid surface.

Hayabusa2 project

2018.09.23. The comment from Takashi Kubota has been corrected.