★ Hayabusa2 status (the week of 2018.10.08) ★
On October 8, the spacecraft returned to the home position at remained there for this week. Project members made the final preparations for the second touchdown rehearsal (TD1-R1-A). Images taken by MASCOT were released by the MASCOT team and the surface conditions of Ryugu were even more apparent. From October 14, the TD1-R1-A operation began.
★ Hayabusa2 status (the week of 2018.10.01) ★
Preparation for the MASCOT separation operation began on September 30 and descent began around noon JST on October 2. On October 3 at 10:57:20 JST, MASCOT was deployed at an altitude of 51m. MASCOT then landed on the surface of Ryugu and proceeded to operate for about 17 hours. The spacecraft then returned to the home position after staying for about 1 day at an altitude of around 3km. Originally, we planned to reach the home position on October 5, but due to the forecast of a typhoon approaching Japan at the weekend, this was delayed until October 8.
★ Hayabusa2 status (the week of 2018.09.24) ★
This week, the MINERVA-II1 rovers that landed on the asteroid last week sent images from the asteroid surface. No regolith was seen in these images, only a shocking scenery of large and small boulders. On the other hand, the scenes of sunlight on the asteroid and the rover hopping were both very beautiful and dynamic. Next week is the deployment of the MASCOT lander. The descent operation is always a nervous time and we want to deliver the lander steadily and carefully. (Regolith: fine grain sediments).
★ Hayabusa2 status（the week of 2018.09.17）★
This week was very exciting. On September 19, preparation began for the separation of the MINERVA-II1 rovers. Descent from the home position began at around 14:00 JST on September 20. On September 21 after 13:00 JST, the two MINERVA-II1 rovers, Rover-1A and Rover-1B separated from the spacecraft. After this, the spacecraft rose and returned to the home position at around 15:00 JST on September 22. After separation, we attempted communication with MINERVA-II1. By September 22, images and data confirmed that both rovers had landed on Ryugu and that at least one was hopping and moving. We published a press release on September 22, releasing the situation of MINERVA-II1 and the acquired images. The Project Members were also very impressed by these images sent from MINERVA-II1.
★ Hayabusa2 status（the week of 2018.09.10）★
The first half of the week was devoted to the landing rehearsal operation (TD1-R1). The operation was suspended at an altitude of 600m, and the spacecraft returned to the base camp 20 km home position. Although TD1-R1 was interrupted, we were able to see the response of Hayabusa2 at low altitude and gain a valuable image of the landing candidate area at high resolution. The Project Team feels that we are narrowing down the unexplored areas step by step. Our analysis of this data continues for the upcoming rover separation and landing operation.
★ Hayabusa2 status（the week of 2018.09.03）★
Last week, we started moving from “BOX-B” and returned to the home position for the spacecraft (“BOX-A”) as scheduled. We have continued to observe the asteroid everyday using the onboard cameras, while frantically preparing for the first touchdown rehearsal that will begin from Sept. 11 and the other operations that will follow. This next descent operation will take about two days to complete, but the preparatory work is taking several dozen times that. To get the best results from this preparation, we need to concentrate through this next week.
★ Hayabusa2 status（the week of 2018.8.27）★
Hayabusa2 has completed operation in BOX-B; observing the asteroid while moving laterally up to 9km while remaining at an altitude of about 20km. As the first rehearsal for touchdown is scheduled to start on 09/11, the spacecraft is now returning to the descent start position. In the first touchdown rehearsal, the spacecraft will descend to 30m or less from the asteroid surface to acquire a more detailed image of the primary touchdown candidate point, L08, and the surroundings. The distance to the asteroid will be measured for the first time using the LRF (Laser Range Finder); a short-distance laser sensor that is used for touchdown. This will be the first time the LRF has been used to measure distance since launch.
★ Hayabusa2 status（the week of 2018.8.20）★
The spacecraft is currently operating in BOX-B. On August 23, we announced to the media that the point denoted “L08” near the asteroid equator had been selected as the candidate site for the touchdown of Hayabusa2. However, the surface of Ryugu is covered with boulders, so we need to continue gathering and considering information so that we can touchdown safely. The MINERVA-II-1 and MASCOT lander decided to land at mid-latitude sites, N6 and MA-9. MINERA-II-1 separation is scheduled for September 21, and MASCOT on October 3. We are looking forward to seeing what kind of data these will collect!
★ Hayabusa2 status（the week of 2018.8.13）★
After returning from the Gravity Measurement Operation, Hayabusa2 operated in BOX-A (the home position). Japan experienced very unsettled weather this week, with thunderstorm around the Usuda Deep Space Centre. In addition to this, thunderstorm occurred at US Goldstone ground station when we operated Hayabusa2 from there. Weather at the ground stations is concerning. Also this week was an active discussion on landing locations. On August 17, a large number of international Project Members gathered to engage in this debate. From August 18, BOX-B operations began and the spacecraft starting moving from BOX-A.
★ Hayabusa2 status（the week of 2018.8.6）★
From August 5 - 7 this week we performed the “Gravity Measurement Descent” operation. This was the second operation in which Hayabusa2 descended towards the asteroid using the same technique as for landing. The final altitude was 851m! At this close approach, the gravity of Ryugu could be sufficiently felt to be measured and we were able to take valuable close-up images. Now at ISAS, researchers are gathering from Japan and abroad. Sagamihara is passionate about the scientific debate on this brand-new astronomical object for humanity.
2018.8.13 Y. T.
★ Hayabusa2 status（the week of 2018.7.30）★
From our descent through BOX-C to an altitude of about 6km last week, we made a fleeting return to BOX-A at a 20km altitude. Then this week, we conducted the “Medium Altitude Observation” operation, which is the first critical operation after arrival. Unlike BOX-C, we descended to an altitude of about 5km in 24 hours while performing strict position control, then hovered at the same altitude for 1 asteroid rotation cycle while observing the asteroid. As the first critical operation, it was a tense period but the operation safely succeeded and I think gave momentum for future operations. Next week, we will implement the “Gravity Measurement Operation” which is a second critical operation.
★ Hayabusa2 status（the week of 2018.7.23）★
This week, we returned from the 6km altitude “BOX-C” to “BOX-A”, staying at an altitude of 20km±1km while images taken at BOX-C were downloaded. The images released on July 25 showed a detailed view of the unevenness of Ryugu’s surface. Meanwhile, we conducted a test on the laser distance measurer, LIDAR, in preparation for the “Middle Altitude Observation Operation”, in which the spacecraft will descend to hover at a 5km altitude and then perform the “Gravity Measurement Descent Operation” which decreases the altitude to just 1km. We are ready!
★ Hayabusa2 status（the week of 2018.7.16) ★
Last week we performed short-term operations at an altitude of about 6 km. This allowed closer observations of Ryugu in more detail and the data downlink is happening now. While usual operations are “BOX-A”, these operations at a different maintenance altitude are called “BOX-C” operations. While we did not keep the order, we will do “BOX-B” operations. Do look forward to these!
★ Hayabusa2 status（the week of 2018.7.9) ★
Operations continue at the Home Position (an altitude of about 20km). Overseas stations as well as the Usuda Deep Space Observatory have also been used for the Ka band downlink and uplink transfer. The ONC-T, LIDAR, NIRS3 and TIR have performed BOX-A (20km altitude) observations, continuing our steady data acquisition.
★ Hayabusa2 status（the week of 2018.7.2) ★
The first week after arriving at Ryugu has gone by in a flash. Monitoring the landscape of a brand-new astronomical object for humanity while continuing spacecraft operations is a wonderful and amazing experience.
The two main activities this week were:
・Establishing the procedure needed to accurately hover 20km above the asteroid.
・An operation check of the observational instruments when directed towards Ryugu.
The outcome of both activities was good. The LIDAR (Laser altimeter) measured the altitude of the asteroid’s facing surface and the Ka-band communication equipment started sending high speed data through the NASA Deep Space Network. From the Doppler shift of the radio waves sent from Hayabusa2, we could tell that the spacecraft is feeling the gravity of the asteroid. Hayabusa2’s exploration of Ryugu in this first week has been a smooth start.
We have carried out the second optical navigation trajectory correction manoeuvre (TCM02)
On June 11, 2018 at around09:30 - 10:40 JST, the thrusters were fired several times to give an acceleration of 13 cm/s (x-direction), 1 cm/s (-y-direction), 26 cm/s (z-direction). The distance from the spacecraft to the asteroid during the manoeuvre was about 1320km and their relative speed after TCM02 was about 2.1m/s. Until now, Hayabusa2 was approaching Ryugu from the side. But with TCM02, the asteroid is now directly in front of the spacecraft, along the direction of travel.
Downlink Test Using Ka-band
Today (June 29, 2016), we made a downlink test using Ka-band,and the result was successful. The antenna of DSS26 in Goldstone, DSN (Deep Space Network) of NASA was used and the calibration for the ground station was done today.
We made the first test of Ka-band in the beginning of January 2015, and the test of today was the second time. The distance between the Earth and the spacecraft is about 50 million km, which is about four times larger than the distance at the first test. We are using the X-band (8 GHz) for the daily operation, and we will use the Ka-band (32 GHx) when the spacecraft arrives at Asteroid Ryugu and send the data of Ryugu to us.