posted 10-25-2013 10:03 AM               

JAXA's Hayabusa2 asteroid explorer mission

The Asteroid Explorer Hayabusa2 is the successor to Hayabusa (MUSES-C). Its mission is to explore one of the C-type asteroids in the universe, retrieve materials and bring them to Earth. The rock of C-type asteroids is considered to contain organic matter and water. Hayabusa2 explores the mystery of the origin of the sea water and the life on the earth in addition to the mystery of the earth's formation.

While Hayabusa recorded a number of world's first achievements, Hayabusa2 will enhance the reliability of exploration technologies. At the same time, Hayabusa2 will challenge to obtain new technologies such as creation of artificial craters, high-speed communications in deep space, and new observation instruments.

In the current plan, the launch window for Hayabusa2 is in 2014. With this schedule, Hayabusa2 would reach the asteroid in the middle of 2018, and return to the Earth at the end of 2020.

Target body to be explored

As of now, the candidate target asteroid of Hayabusa2 is called 1999 JU3. Asteroid 1999 JU3 is one of the Near Earth Objects (NEO) that come close to the Earth's orbit. This asteroid is about 900 meters in size and its rotation period is about 7.6 hours. The albedo of the surface is low, estimated about 0.06, and its approximate shape and spin axis inclination have been estimated.

While the asteroid Itokawa explored by Hayabusa is an S-type asteroid, 1999 JU3 is classified as a C-type asteroid. An asteroid is considered to have information about the birth of the solar system and its later evolution.

For a large celestial body such as Earth, its original materials were melted once, and consequently there is no way to reach the history before melting. On the other hand, most of hundreds of thousands asteroids and comets which we found at this point preserve history of the place and era of their birth within the solar system.

Exploring such celestial bodies brings us an opportunity to know how the solar system was born and formed, and how the original materials of life on Earth were created and evolved in space.

Mission

After arriving at the target asteroid, Hayabusa2 will observe using a variety of remote-sensing instruments, small lander and rover.

Hayabusa2 is planning to carry the German/French lander on board through the international cooperation as well as Japanese rovers. They will be released from Hayabusa2 and will land on the asteroid, then perform observations of the surface of asteroid in detail. The Hayabusa2 will then touch down and collect samples from asteroid surface.

Furthermore, an impactor which is newly developed, Hayabusa2 will create an artificial crater by the impactor and will collect samples from the crater, which means that we can obtain the subsurface material of asteroid.

posted 11-30-2014 06:09 PM               

Hayabusa2 set to launch to asteroid

Mitsubishi Heavy Industries and the Japan Aerospace Exploration Agency (JAXA) have scheduled the launch of the asteroid explorer Hayabusa2 for Tuesday (Dec. 2) at 11:22 p.m. EST (0422 GMT, 1:22 pm local time Dec. 3) atop the H-IIA Launch Vehicle No. 26 (H-IIA F26) from the Tanegashima Space Center in Japan.

The launch had previously been scheduled for Nov. 30 but was delayed twice due to predicted strong winds at the launch site. The launch may be delayed further depending on weather conditions and other factors.

Hayabusa2 is slated to arrive at asteroid 1993 JU3 in mid-2018 to collect samples before returning to Earth in 2020.

posted 12-03-2014 03:01 AM               

Hayabusa2 launches to asteroid 1993 JU3

The Japan Aerospace Exploration Agency (JAXA) and Mitsubishi Heavy Industries launched the Hayabusa2 asteroid sample mission on Tuesday (Dec. 22) at 11:22 p.m. EST (0422 GMT Dec. 3) atop a H-2A rocket from the Tanegashima Space Center in Japan.

"The launch vehicle flew as planned, and at approximately one hour, 47 minutes and 21 seconds after liftoff, separation of the Hayabusa2 to earth-escape trajectory was confirmed," JAXA reported.

The asteroid explorer is a successor to the original Hayabusa, which returned to Earth samples from asteroid Itokawa in 2010. Hayabusa2's scientific mission to asteroid 1993 JU3 is to help clarify the origin and evolution of the solar system, as well as the building blocks of life.

posted 06-04-2018 08:12 AM               

Completion of forward cruise ion engine operation

Since January 10 this year (2018), the third phase of the ion engine operation has been underway. This was completed this week on June 3, ending the use of the ion engines for the outward approach towards asteroid Ryugu.

During the operation on June 3, Hayabusa2's velocity was confirmed via Doppler data (the shift in radio wave frequency corresponding to the speed of the spacecraft along the line-of-sight from Earth) and the decision was made to stop ion engine operation at 14:59 JST at machine time (the time recorded by Hayabusa2's on-board clock). The telemetry data from the spacecraft received at 15:16 confirmed that ion engine operation has ended normally.

In this third phase of ion operation, the continuous operation time was about 2,426 hours, producing a velocity increase of 393 m/s (hourly speed of 1,400 km/hr).

From here on, accurate orbital determination of both the spacecraft and the asteroid will be made via radio and optical navigation as Hayabusa2 approaches Ryugu.

posted 06-14-2018 08:26 AM               

Ryugu seen from a distance of 920km

Hayabusa2 is steadily approaching asteroid Ryugu.

Figure 1 shows a photograph of Ryugu taken on June 13, 2018 with the ONC-T (Optical Navigation Camera - Telescopic) from a distance of about 920km. The celestial body shining brightly in the center of the frame is Ryugu. The movement of Ryugu (in comparison to the background stars) can be seen by comparing this image with those taken on June 6 and June 10. The brightness of Ryugu is now about -6.6 mag (astronomical magnitude: a logarithmic scale for the apparent brightness for an object).

Figure 2 shows the photograph taken with an exposure time of about 0.09 seconds. The part of the image that covers Ryugu is now about 10 pixels in diameter. We are describing the shape seen so far as a "dango"-type, as it looks like the round dango Japanese sweet dumpling made from rice flour (they taste delicious and we can recommend trying one). However, the shape does seem a little more angular.

These images were taken on June 13th, the same day that Hayabusa returned to Earth eight years ago. Just eight years later, Hayabusa2 is less than 1000 km from asteroid Ryugu. We are looking forward to seeing what developments come next!

posted 06-19-2018 07:37 AM               

Ryugu seen from 330-240km

The ONC-T (Optical Navigation Camera - Telescopic) captured images of Ryugu on June 17, 2018 at around 15:00 JST and June 18 at around 06:00 JST. At 15:00 JST on June 17, the distance to Ryugu was approximately 330 km, which had decreased to 240 km by June 18 at 06:00 JST.

The following figures show the original images taken by the ONC-T, without any pixel smoothing. The order of the photographs is not chronological, but show the sequential rotation of the asteroid. The change in distance is compensated by keeping the size of the asteroid constant through the image set.

This next image set is the same as the previous photographs, but with the pixels smoothed and G image processing applied which emphasizes light and dark regions.

Comment by Project Scientist, Sei-ichiro Watanbe

The vertical direction in these images is tilted by 10 degrees counterclockwise compared to the vertical direction of the orbital plane of Ryugu. From looking between the multiple images in this set, you can see that the vertical direction is nearly perpendicular to the plane of revolution of the asteroid. We call this direction the asteroid's axis of rotation. The direction of the rotation is reversed compared to the Earth, with a rotation period of about 7.5 hours.

The diameter of Ryugu is about 900m, which is consistent with the prediction from ground observations. However, since the distance between the spacecraft and Ryugu is not precisely determined, there is still some uncertainty in the exact diameter at this time.

The shape of the asteroid looks like a spinning top (called a "Coma" in Japanese), with the equatorial part wider than the poles. This form is seen in many small asteroids that are rotating at high speed. Observed by radar from the ground, asteroid Bennu (the destination of the US mission, OSIRIS-REx), asteroid Didymous (the target of the US DART project), and asteroid 2008 EV5 that is approaching the Earth, all have a similar shape.

On the surface of asteroid Ryugu, you can see a number of crater-like round recessed landforms. In the first image, one large example can be seen with a diameter exceeding 200m. This moves to the left and darkens as the asteroid rotates and the lower part becomes cast in shadows.

The bulge at the equator forms a ridge around the asteroid like a mountain range. Outside this, the surface topology appears very ridge-shaped and rock-like bulges are also seen. These details should become clearer as the resolution increases in the future.

Comment by Mission Manager, Makoto Yoshikawa

When I saw these images, I was surprised that Ryugu is very similar in shape to both the destination of the US OSIRIS-REx mission, asteroid Bennu, and also the target of the previously proposed MarcoPolo-R mission by Europe, asteroid 2008 EV5. Bennu and 2008 EV5 are about half the diameter (and 1/8 the volume) of Ryugu, with rotation periods about half as long. In other words, these celestial bodies are small and rotating fast compared to Ryugu.

On the other hand, Bennu is a B-type asteroid, which is very similar to C-type asteroids such as 2009 EV5 and Ryugu. Therefore there should also be common properties due to the asteroid type. So we have both differences and similarities that have combined to produce very similar shapes... why is that? I think this is very interesting. So far, the asteroids we have explored have been different in shape, so Ryugu and Bennu could be the first time two similar-shaped asteroids have been examined. It will be interesting to clarify exactly what this similarity means scientifically.

If the axis of rotation for Ryugu is close to the vertical direction in this image, there is a big advantage as it will be possible to know almost the entire appearance of Ryugu at an early stage after arrival. This makes the project planning easier. However, it is also possible that potential landing sites may be limited to the equator of Ryugu. I hope we can find a suitable place to set down the lander and rovers.

posted 06-27-2018 08:24 AM               

Asteroid Ryugu seen from a distance of around 40km

Hayabusa2 is close to arriving at asteroid Ryugu. After a journey of around 3.2 billion km since launch, our destination is finally near. Two small objects will soon meet in outer space 280 million km from the Earth.

Figure 1 shows Ryugu photographed by the ONC-W1 (Optical Navigation Camera - Wide angle) on June 24, at about 15:00 JST. We can see Ryugu floating in the jet black of space.

Figure 2 shows Ryugu photographed with the ONC-T (Optical Navigation Camera - Telescopic) on June 24, at around 00:01 JST. The appearance of the surface has now become much clearer. The distance between the spacecraft and the asteroid when this photo was taken was about 40 km.

Comment by Project Manager, Yuichi Tsuda

The shape of Ryugu is now revealed. From a distance, Ryugu initially appeared round, then gradually turned into a square before becoming a beautiful shape similar to fluorite [known as the 'firefly stone' in Japanese]. Now, craters are visible, rocks are visible and the geographical features are seen to vary from place to place. This form of Ryugu is scientifically surprising and also poses a few engineering challenges.

First of all, the rotation axis of the asteroid is perpendicular to the orbit. This fact increases the degrees of freedom for landing and the rover decent operations. On the other hand, there is a peak in the vicinity of the equator and a number of large craters, which makes the selection of the landing points both interesting and difficult. Globally, the asteroid also has a shape like fluorite (or maybe an abacus bead?). This means we expect the direction of the gravitational force on the wide areas of the asteroid surface to not point directly down. We therefore need a detailed investigation of these properties to formulate our future operation plans.

The Project Team is fascinated by the appearance of Ryugu and morale is rising at the prospect of this challenge. Together with all of you, we have become the first eyewitnesses to see asteroid Ryugu. I feel this amazing honor as we proceed with the mission operations.

posted 07-11-2018 11:24 AM               

The view of Ryugu from the home position

From the "home position" at 20 km away from asteroid Ryugu, Hayabusa2 has been confirming instrument operations in preparation for future observations. The images below show the results of part of this rehearsal observation.

Above: Asteroid Ryugu photographed with the ONC-T from a distance of about 20 km. The image was taken at around 23:13 JST on June 30, 2018.

Above: Ryugu photographed with the ONC-T from a distance of about 20 km. This image was taken at around 19:21 JST on June 30, 2018. As the asteroid has rotated, this image is almost the reverse side of Figure 1.

Credit: JAXA, University of Tokyo, Kochi University, Rikkyo University, Nagoya University, Chiba Institute of Technology, Meiji University, University of Aizu and AIST

posted 09-07-2018 03:17 PM               

Determination of landing site candidates!

The Landing Site Selection (LSS) conference was held on August 17, 2018 and the candidate landing locations for touchdown, MASCOT and MINERVA-II-1 on the surface asteroid Ryugu were decided. In this article, we introduce the landing candidate spots and the planned dates for these surface operations, along with details of the selection.

Figure 1 is a map of asteroid Ryugu showing the landing candidate locations. Please note the direction of north and south on this map.

Note: On the map shown in Figure 1, the north pole of the asteroid is on the top of the map. Public images released so far show the asteroid orientated in the opposite direction, with the direction of the Solar System's north and for the Earth's North Pole) at the top. Geographical north and south of the asteroid is determined by rotation. As Ryugu rotates retrograde, in the opposite direction to the Earth and the Solar System, the asteroid's northern direction is reversed with respect to the Solar System. The situation is the same for Itokawa. An image with the asteroid's north at the top is therefore reversed compared to an image where the Solar System north points upwards.

The areas within the colored lines in Figure 1 are the candidate areas for the landing sites for the touchdown of the Hayabusa2 mothership (for sampling), MASCOT and MINERVA-II-1. These are labelled as:

• Touchdown: L08 (backup sites: L07, M04)
  
• MASCOT: MA-9
  
• MINERVA-II-1: N6

L08 is the first choice (primary) candidate for the mothership's touchdown, with L07 and M04 as back-up options. The designation "L" and "M" refer to low latitude (L) and mid-latitude (M) positions. The "L" candidate positions were selected from among 13 preliminary candidate sites, while the "M" location was chosen from a set of four candidate sites. The size of the site selection rectangles are approximately 100m. MA-9 was selected as the candidate landing site for MASCOT from ten possibilities, while the N6 candidate for MIENRA-II-1 was chosen from seven surface locations.

In Figure 2, each candidate region is shown on the ONC-T image taken during the BOX-C observations at an altitude of 6km. Also in this image, the top of the asteroid is the north pole.

Following the determination of the landing site candidates, the operation schedule is as follows:

posted 09-21-2018 09:25 AM               

Hayabusa2 deploys MINERVA-II 1 rovers

JAXA's Hayabusa2 probe deployed its first two landers, the MINERVA II 1 (MIcro Nano Experimental Robot Vehicle for Asteroid, the second generation) rovers 1A and 1B, at about 12:35 a.m. EDT on Friday (Sept. 21) after descending toward Ryugu and coming within 200 feet of the asteroid's surface.

From the mission's Twitter account:

Heeeeeeere weeeeee cooooome!!!!!!!!!

The two MINERVA-II 1 rovers are hexagonal in shape with a diameter of 7 inches (18 cm), height of 3 inches (7 cm) and weigh about 2.4 pounds (1.1 kg) each.

There are four cameras on Rover-1A and three cameras on Rover-1B that will be used to create a stereo image of the surface of Ryugu. The rovers are also equipped with sensors to measure the surface temperature of Ryugu.

The main feature of MINERVA-II 1 rovers is their ability to move. Within the rover is a motor that rotates and causes the rover to "hop" (jump up) during the rebound. This will allow the rovers to autonomously move across the asteroid surface and explore multiple areas.

Due to the low gravity on Ryagu, the rover is expected to remain aloft for up to 15 minutes after a single hop before landing, and to move up to 50 feet (15 m) horizontally.

posted 09-22-2018 10:18 AM               

MINERVA-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.

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.

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.

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.

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 ground station 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.

posted 09-27-2018 08:00 AM               

MINERVA-II1: Images from the surface of Ryugu

The MINERVA-II1 rovers were deployed on September 21 to explore the surface of asteroid Ryugu. Here is the second report on their activities, following our preliminary article at the start of this week. We end this report with a video taken by one of the rovers that shows the Sun moving across the sky as seen from the surface of Ryugu. Please take a moment to enjoy "standing" on this new world.

Rover-1B hop

Figure 1. Images taken by Rover-1B. September 23, 2018: confirmation of Rover-1B hop. Observation time (JST): (Left) 2018-09-23 09:50, (Right) 2018-09-23 09:55, (Below) 2018-09-23 10:00.

Image captured immediately before hop of Rover-1B

Figure 2. September 23, 2018: image captured immediately before hop of Rover-1B. 2018-9-23 09:46 (JST).

Surface image from Rover-1B after landing

Figure 3. September 23, 2018 at 10:10 JST: surface image from Rover-1B after landing.

Surface image taken from Rover-1A

Figure 4. September 23, 2018 at 09:43 JST: surface image taken from Rover-1A.

Rover-1A captured the shadow of its own antenna and pin

Figure 5. September 23, 2018 at 09:48 JST: surface image taken from Rover-1A. MINERVA-II1 successfully captured the shadow of its own antenna and pin.

The pins on the MINERVA-II rovers have three roles:

1. To increase friction when hopping
   
2. Protect the solar cells during landing
   
3. A few of the pins also have a temperature sensor, so surface temperature can be measured directly.

Rover-1B successfully shot a movie

Figure 6. (movie) Rover-1B successfully shot a movie. 15 frames captured on September 23, 2018 from 10:34 – 11:48 JST.

posted 10-03-2018 07:49 AM               

MASCOT lands safely on asteroid Ryugu

The near-Earth asteroid Ryugu, located approximately 300 million kilometres from Earth, has a new inhabitant: On 3 October 2018, the Mobile Asteroid Surface Scout (MASCOT) landed on the asteroid and began to work.

The lander successfully separated from the Japanese Hayabusa2 space probe at 03:58 CEST. The 16 hours in which the lander will conduct measurements on the asteroid’s surface have begun for the international team of engineers and scientists.

The day before, the Japanese Space Agency's Hayabusa2 began its descent towards Ryugu. MASCOT was ejected at an altitude of 51 metres and descended in free fall – slower than an earthly pedestrian – to its destination, the asteroid. The relief about the successful separation and subsequent confirmation of the landing was clearly noticeable In the MASCOT Control Centre at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) as well as in the adjoining room: "It could not have gone better," explained MASCOT project manager Tra-Mi Ho from the DLR Institute of Space Systems. "From the lander's telemetry, we were able to see that it separated from the mothercraft, and made contact with the asteroid surface approximately 20 minutes later." The team is now in contact with the lander.

The moment of separation was one of the risks of the mission: If MASCOT had not successfully separated from Hayabusa2 as planned and often tested, the lander’s team would hardly have had the opportunity to solve this problem. But everything went smoothly: Already during the descent on the asteroid, the camera switched MASCAM on and took 20 pictures, which are now stored on board the Japanese space probe. "The camera worked perfectly," says Ralf Jaumann, DLR planetary scientist and scientific director of the camera instrument. "The team's first images of the camera are therefore safe."

The magnetometer team was also able to recognise in the data sent by MASCOT that the MASMAG instrument had switched on and performed measurements prior to the separation. "The measurements show the relatively weak field of the solar wind and the very strong magnetic disturbances caused by the spacecraft," explains Karl-Heinz Glaßmeier from the Technical University of Braunschweig. "At the moment of the separation, we expected a clear decrease of the interference field – and we were able to recognise this clearly."

MASCOT came to rest on the surface approximately 20 minutes after the separation. Now, the team is analysing the data that MASCOT is sending to Earth to understand the events occurring on the asteroid Ryugu. The lander should now be on the asteroid’s surface, in the correct position thanks to its swing arm, and have started to conduct measurements independently.

There are four instruments on board: a DLR camera and radiometer, an infrared spectrometer from the Institut d'Astrophysique Spatiale and a magnetometer from the TU Braunschweig. Once MASCOT has performed all planned measurements, it is expected to hop to another measuring location. This is the first time that scientists will receive data from different locations on an asteroid.

"With MASCOT, we have the unique opportunity to study the Solar System’s most primordial material directly on an asteroid," emphasises DLR planetary researcher Ralf Jaumann. With the data acquired by MASCOT and the samples that Hayabusa2 brings to Earth from Ryugu in 2020, scientists will not only learn more about asteroids, but more about the formation of the Solar System. "Asteroids are very primordial celestial bodies."

Hayabusa2 is a Japanese space agency (Japan Aerospace Exploration Agency; JAXA) mission to the near-Earth asteroid Ryugu. The German-French lander MASCOT on board Hayabusa2 was developed by the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) and built in close cooperation with the French space agency CNES (Centre National d'Etudes Spatiales). DLR, the Institut d'Astrophysique Spatiale and the Technical University of Braunschweig have contributed the scientific experiments on board MASCOT. The MASCOT lander and its experiments are operated and controlled by DLR with support from CNES and in constant interaction with the Hayabusa2 team.

posted 10-05-2018 10:50 AM               

Three hops in three asteroid days – MASCOT successfully completes the exploration of the surface of asteroid Ryugu

It was a day full of exciting moments and a happy team of scientists and engineers: late in the afternoon of 3 October 2018, the German-French lander MASCOT completed its historic exploration of the surface of the asteroid Ryugu at 21:04 CEST, as its battery ran out.

On-asteroid operations were originally scheduled to last 16 hours after separation from the Japanese mothercraft Hayabusa2. But in the end, the battery lasted more than 17 hours.

Upon landing in the early morning and subsequently relocating using the built-in swing arm, all instruments collected detailed data on the composition and nature of the asteroid. The on-board camera provided pictures of the landing, hopping manoeuvres and various locations on the surface.

For MASCOT, the Sun set three times on Ryugu. The lander was commanded and controlled from the MASCOT Control Centre at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) in Cologne, in the presence of teams of scientists from Japan, France and Germany. All scientific data was transferred to the mother probe according to plan.

"With MASCOT, it has been possible to, for the first time, explore the surface of an asteroid directly on site so extensively," says Hansjörg Dittus, DLR Executive Board Member for Space Research and Technology. "A mission like this can only be done working in close cooperation with international partners – bringing together all their expertise and commitment." With MASCOT, DLR has been working closely with the Japanese space agency JAXA and the French space agency CNES.

Jumps and a mini-move

MASCOT landed safely on Ryugu in the early morning of 3 October 2018.

"After a first automated reorientation hop, it ended up in an unfavourable position. With another manually commanded hopping manoeuvre, we were able to place MASCOT in another favourable position thanks to the very precisely controlled swing arm," says MASCOT operations manager Christian Krause from DLR.

Above: Hayabusa2 acquires images of MASCOT on its approach to Ryugu. Three consecutive images acquired on 3 October 2018 between 03:57:54 and 03:58:14 CEST with the wide-angle optical navigation camera (ONC-W2). MASCOT can be seen at the top. (JAXA, Tokyo University, Kochi Univ., Rikkyo Univ., Nagoya Univ., Chiba Institute of Technology, Meiji Univ., Aizu Univ., AIST)

From that position, MASCOT completed a complete measurement sequence with all instruments over one asteroid day and an asteroid night.

"Later, we were able to continue the activities on Ryugu with a special manoeuvre," adds Ralf Jaumann, DLR planetary scientist and scientific director of MASCOT. "With a 'mini-move' we recorded image sequences that will be used to generate stereo images of the surface once they have been analysed."

During the first manoeuvres, MASCOT moved several metres to the next measuring point. Finally, and seeing that the lander still had battery power left, the researchers dared to make a bigger jump.

All in all, MASCOT explored Ryugu for three asteroid days and two asteroid nights. A day-night cycle on Ryugu lasts about 7 hours and 36 minutes. At 21:04 CEST, communications with Hayabusa2 were interrupted, because of the radio shadow entering with each asteroid rotation. Hayabusa2 is now returning to its home position, at an altitude of 20 kilometres above the asteroid's surface.

In addition to the images acquired by the DLR camera MASCAM, a DLR radiometer, a magnetometer from TU Braunschweig and a spectrometer from the Institut d'Astrophysique Spatiale provided a variety of measurements on the temperature, magnetic properties and the composition of the near-Earth asteroid Ryugu.

Waiting for the scientific data

MASCOT is now a silent inhabitant of Ryugu.

"The evaluation of the valuable data has just begun," says MASCOT project manager Tra-Mi Ho from the DLR Institute of Space Systems. "We will learn a lot about the past of the Solar System and the importance of near-Earth asteroids like Ryugu. Today, I look forward to the scientific publications that will result from MASCOT and the remarkable Hayabusa2 mission of our Japanese partners."

Hayabusa2 played a crucial role in the success of MASCOT. The Japanese probe brought the lander to the asteroid. Thanks to precise planning and control, the communication links to the lander could be optimally used for data transmission, so that the first pictures were received on the very day of landing. The remaining scientific data, which was transmitted to Hayabusa2, will be sent to Earth in the coming days.

posted 10-14-2018 11:34 PM               

Numerous boulders, many rocks, no dust: MASCOT's zigzag course across the asteroid Ryugu

Six minutes of free fall, a gentle impact on the asteroid and then 11 minutes of rebounding until coming to rest. That is how, in the early hours of 3 October 2018, the journey of the MASCOT asteroid lander began on Asteroid Ryugu – a land full of wonder, mystery and challenges. Some 17 hours of scientific exploration followed this first "stroll" on the almost 900-metre diameter asteroid.

The lander was commanded and controlled from the MASCOT Control Centre at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) site in Cologne in the presence of scientific teams from Germany, France and Japan. MASCOT surpassed all expectations and performed its four experiments at several locations on the asteroid. Never before in the history of spaceflight has a Solar System body been explored in this way. It has now been possible to precisely trace MASCOT's path on Ryugu's surface on the basis of image data from the Japanese Hayabusa2 space probe and the lander's images and data.

Above: MASCOT's approach to Ryugu and its path across the surface.

"This success was possible thanks to state-of-the-art robotic technology, long-term planning and intensive international cooperation between the scientists and engineers of the three space nations Japan, France and Germany," says Hansjörg Dittus, DLR Executive Board Member for Space Research and Technology about this milestone in Solar System exploration. "We are proud of how MASCOT was able to master its way across the asteroid Ryugu over boulders and rocks and send so much data about its composition back to Earth," says DLR Chair Pascale Ehrenfreund.

MASCOT had no propulsion system and landed in free fall. Six minutes after separating from Hayabusa2, and following the end of a ballistic trajectory, the landing module made its first contact with asteroid Ryugu. On the surface, MASCOT moved through the activation of a tungsten swing arm accelerated and decelerated by a motor. This made it possible for MASCOT to be repositioned to the 'correct' side or even perform hops across the asteroid's surface. The gravitational attraction on Ryugu is just one 66,500th of the Earth's, so the little momentum provided was enough: a technological innovation for an unusual form of mobility on an asteroid surface used for the first time in the history of space travel as part of the Hayabusa2 mission.

Above: MASCOT's image of Ryugu's south polar region shortly after separation.

Through a rock garden full of rough boulders and no flat surfaces

To reconstruct MASCOT's path across the surface of Ryugu, the cameras aboard the Hayabusa2 mother probe were aimed at the asteroid. The Optical Navigation Cameras (ONC) captured the lander's free fall in several images, detected its shadow on the ground during the flight phase, and finally identified MASCOT directly on the surface in several images. The pattern of the countless boulders distributed on the surface could also be seen in the direction of the respective horizon in oblique photographs of the lander's DLR MASCAM camera. The combination of this information unlocked the unique path traced by the lander.

Above: MASCOT image pointing east while descending on Ryugu.

After the first impact, MASCOT smoothly bounced off a large block, touched the ground about eight times, and then found itself in a resting position unfavorable for the measurements. After commanding and executing a specially prepared correction maneuver, MASCOT came to a second halt. The exact location of this second position is still being determined. There, the lander completed detailed measurements during one asteroid day and night. This was followed by a small 'mini-move' to provide the MicrOmega spectrometer with even better conditions for measuring the composition of the asteroid material.

Finally, MASCOT was set in motion one last time for a bigger jump. At the last location it carried out some more measurements before the third night on the asteroid began, and contact with Hayabusa2 was lost as the spaceship had moved out of line of sight. The last signal from MASCOT reached the mother probe at 21:04 CEST. The mission was over. "We were expecting less than 16 hours of battery life because of the cold night, says MASCOT project manager Tra-Mi Ho from the DLR Institute of Space Systems. "After all, we were able to operate MASCOT for more than one extra hour, even until the radio shadow began, which was a great success." During the mission, the team named MASCOT's landing site (MA-9) "Alice's Wonderland," after the eponymous book by Lewis Carroll (1832-1898).

Above: MASCOT's fourth image during the descent to Ryugu.

A true wonderland

Having reconstructed the events that took place on asteroid Ryugu, the scientists are now busy analyzing the first results from the acquired data and images. "What we saw from a distance already gave us an idea of what it might look like on the surface," reports Ralf Jaumann from the DLR Institute of Planetary Research and scientific director of the MASCOT mission. "In fact, it is even crazier on the surface than expected. Everything is covered in rough blocks and strewn with boulders. How compact these blocks are and what they are composed of, we still do not know. But what was most surprising was that large accumulations of fine material are nowhere to be found – and we did not expect that. We have to investigate this in the next few weeks, because the cosmic weathering would actually have had to produce fine material," continues Jaumann.

"MASCOT has delivered exactly what we expected: an 'extension' of the space probe on the surface of Ryugu and direct measurements on site," says Tra-Mi Ho. Now there are measurements across the entire spectrum, from telescope light curves from Earth to remote sensing with Hayabusa2 through to the microscopic findings of MASCOT. "This will be of enormous importance for the characterization of this class of asteroids," emphasizes Jaumann.

Above: After first contact with the surface: the landing site environment.

Ryugu is a C-type asteroid – a carbon-rich representative of the oldest bodies of the four-and-a-half-billion year-old Solar System. It is a "primordial" building block of planet formation, and one of 17,000 known Near-Earth asteroids.

On Earth, there are meteorites with a composition that could be similar to Ryugu's, which are found in the Murchison Range, Australia. However, Matthias Grott from the DLR Institute of Planetary Research and responsible for the radiometer experiment MARA is skeptical as to whether these meteorites are actually representative of Ryugu in terms of their physical properties: "Meteorites such as those found in Murchison are rather massive. However, our MARA data suggests the material on Ryugu is slightly more porous. The investigations are just beginning, but it is plausible to assume that small fragments of Ryugu would not survive the entry into the Earth's atmosphere intact."

posted 02-21-2019 08:50 PM               

Hayabusa2 Latest Status, the Successful First Touchdown

National Research and Development Agency Japan Aerospace Exploration Agency (JAXA) executed the asteroid explorer Hayabusa2 operation to touch down the surface of the target asteroid Ryugu for sample retrieval.

Data analysis from Hayabusa2 confirms that the sequence of operation proceeded, including shooting a projectile into the asteroid to collect its sample material. The Hayabusa2 spacecraft is in nominal state. This marks the Hayabusa2 successful touchdown on Ryugu.

posted 04-05-2019 08:50 AM               

Asteroid Explorer Hayabusa2's SCI Put into Operation

The National Research and Development Agency Japan Aerospace Exploration Agency (JAXA) separated the SCI (Small Carry-on Impactor) onboard the asteroid explorer Hayabusa2 for deployment to Ryugu and put the SCI into operation.

After the start of the operation, the camera (DCAM3) separated from Hayabusa2 captured an image that shows ejection from Ryugu's surface, which implies that the SCI had functioned as planned.

Hayabusa2 is operating normally. We will be providing further information once we have confirmed whether a crater has been created on Ryugu.

Above: This image captured by the camera separated from Hayabusa2 (DCAM3) shows ejection from Ryugu's surface, which was caused by the collision of the SCI against Ryugu. Image taken at 11:36 a.m., April 5, 2019 (Indicated by the camera, Japan time).

posted 04-26-2019 09:41 AM               

Successful Operation of Asteroid Explorer Hayabusa2's SCI

Japan Aerospace Exploration Agency (JAXA) separated the SCI (Small Carry-on Impactor), which had been onboard the asteroid explorer Hayabusa2, on April 5, 2019, for deployment to Ryugu, and then put the SCI into operation.

As a result of checking the images captured by the Optical Navigation Camera - Telescopic (ONC-T) onboard the asteroid explorer Hayabusa2, we have concluded that a crater was created by the SCI.

Hayabusa2 is operating normally.

Above: Left image: Taken on March 22, 2019. Right image: Taken on April 25, 2019. These images were captured by the Optical Navigation Camera - Telescopic onboard Hayabusa2. By comparing the two images, we have confirmed that an artificial crater was created in the area surrounded by dotted lines. The size and depth of the crater are now under analysis.

posted 07-11-2019 03:54 PM               

Success of the Second Touchdown of Asteroid Explorer 'Hayabusa2'

The Japan Aerospace Exploration Agency (JAXA) performed a series of operations for the second touchdown of Asteroid Explorer "Hayabusa2" on the Ryugu asteroid and the collection of its soil samples.

From the data sent from Hayabusa2, it has been confirmed that the touchdown sequence, including the discharge of a projectile for sampling, was completed successfully. Hayabusa2 is functioning normally, and thus the second touchdown ended with success.

posted 11-13-2019 09:08 AM               

Hayabusa2 departs from Ryugu

JAXA confirmed Hayabusa2, JAXA's asteroid explorer, left the target asteroid Ryugu.

On November 13, 2019, JAXA operated Hayabusa2 chemical propulsion thrusters for the spacecraft's orbit control.* The confirmation of the Hayabusa2 departure made at 10:05 a.m. (Japan Standard Time, JST) was based on the following data analyses;

• The thruster operation of Hayabusa2 occurred nominally
  
• The velocity leaving from Ryugu is approximately 9.2 cm/s
  
• The status of Hayabusa2 is normal

We are planning to conduct performance tests of onboard instruments, including the electric propulsion system, for the return to Earth.

* Hayabusa2 operation hours: 8:00 a.m. (JST) through 13:30 p.m. (JST), November 13. The thruster operation was pre-programmed in the event sequence earlier on the day, and the command was automatically executed.

posted 07-14-2020 08:57 AM               

JAXA-the Australian Space Agency Joint Statement for Cooperation in the Hayabusa2 Sample Return Mission

Dr. Hiroshi Yamakawa, President, the Japan Aerospace Exploration Agency (JAXA) and Dr. Megan Clark AC, Head, the Australian Space Agency (the Agency) released a joint statement dated July 14 2020. The statement acknowledges that the capsule of 'Hayabusa2' containing the asteroid samples will land in South Australia on December 6, 2020.

JAXA and the Agency are working through JAXA's plan for the re-entry and recovery of the capsule. The plan will be finalized by the issuance of Authorisation of Return of Overseas Launched Space Object (AROLSO) from the Australian government.

Joint Statement for Cooperation in the Hayabusa2 Sample Return Mission by the Australian Space Agency and the Japan Aerospace Exploration Agency

The Australian Space Agency (the Agency) and the Japan Aerospace Exploration Agency (JAXA) have been in close cooperation on JAXA's asteroid sample-return mission, 'Hayabusa2'. The sample capsule is planned to land in Woomera, South Australia and the Agency and JAXA are working towards the planned safe re-entry and recovery of the capsule containing the asteroid samples.

Recently, JAXA indicated that 6 December 2020 (Australia/Japan time) is its planned target date for the capsule re-entry and recovery. The Agency and JAXA are working through JAXA's application for Authorisation of Return of Overseas Launched Space Object (AROLSO), which will need to be approved under the Space Activities Act (1998).

Successfully realizing this epoch-making sample return mission is a great partnership between Australia and Japan and will be a symbol of international cooperation and of overcoming the difficulties and crisis caused by the pandemic.

posted 08-18-2020 08:50 PM               

The Hayabusa2 Re-entry Capsule Approved to Land in Australia

On August 10, 2020, JAXA was informed that the Authorisation of Return of Overseas-Launched Space Object (AROLSO) for the re-entry capsule from Hayabusa2 was issued by the Australian Government. The date of the issuance is August 6, 2020.

The Hayabusa2 re-entry capsule will return to Earth in South Australia on December 6, 2020 (Japan Time and Australian Time). The landing site will be the Woomera Prohibited Area. The issuance of the AROLSO gave a major step forward for the capsule recovery.

We will continue careful operation for return of Hayabusa2 and recovery of the capsule, and the operation status will be announced in a timely manner.

Comment from JAXA President, Hiroshi Yamakawa

"The approval to carry out the re-entry and recovery operations of the Hayabusa2 return sample capsule is a significant milestone. We would like to express our sincere gratitude for the support of the Australian Government as well as multiple organizations in Australia for their cooperation.

"We will continue to prepare for the successful mission in December 2020 in close cooperation with the Australian Government."

posted 12-05-2020 03:00 PM               

JAXA's Hayabusa2 probe returns asteroid Ryugu samples to Earth

A Japanese probe has returned asteroid samples to Earth, dropping its cache over Australia before heading out to study more space rocks.

The Hayabusa2 reentry capsule descended to a soft landing within the Woomera Range Complex in the South Australian outback on Saturday (Dec. 5), completing the primary goal of the Japan Aerospace Exploration Agency's (JAXA) second asteroid sample return mission.

posted 12-15-2020 08:25 AM               

Confirmation of the asteroid Ryugu sample collection by the asteroid explorer, Hayabusa2

The Japan Aerospace Exploration Agency is pleased to confirm that samples from asteroid Ryugu have been collected within the sample container inside the re-entry capsule of the asteroid explorer, Hayabusa2.

The Hayabusa2 re-entry capsule was recovered in Woomera, Australia on December 6, 2020 and delivered to the JAXA Sagamihara Campus on December 8. Work then began to open the sample container inside the re-entry capsule.

On December 14, a sample of grains of black sand thought to be derived from asteroid Ryugu was confirmed to be inside the sample container. These are believed to be particles attached to the entrance of the sample catcher (the container in which the samples have been stored).

Work will continue with opening the sample catcher that sits in the sample container. The curation and initial analysis team will remove the samples and proceed with the analysis.

posted 12-28-2020 08:50 AM               

Images of the samples from Ryugu

Images taken after opening the sample container and sample catcher.

Opening the sample container: Observing the bottom of the sample container from above. Black-colored grains from Ryugu can be seen at the bottom of the sample container, which is outside the chambers in the sample catcher.

Inside the sample container captured by a scope camera.

Samples confirmed in sample catcher chamber A: Close-up of the samples in chamber A, color-corrected to allow for the orange ambient light in the curation facility.

The opened sample catcher chamber A.

Sample catcher chamber A, captured by an optical microscope.

Many particles larger than 1mm were found in both chambers A and C. It appears that the particles in chamber C are typically bigger than those in chamber A. Chamber C material was gathered during the second touchdown, which is expected to contain subsurface material ejected from the creation of the artificial crater.

Sample catcher chamber C, captured by an optical microscope.

Artificial material seems to be present in chamber C. The origin is under investigation, but a probable source is aluminium scraped off the spacecraft sampler horn as the projectile was fired to stir up material during touchdown.