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Raumfahrt - JAXA´s Asteroid Explorer Hayabusa-2 auf Asteroid 1999 JU3 gelandet-Update-18

17.09.2019

Navigation Images from the target marker
separation operation (TM-ORB) (Real time delivery)

We are currently delivering navigation images with the Optical Navigation Camera - Telescopic (ONC-T) in real time.
Please understand that the image may be distorted due to the network status or data processing.

  • Images wil be delibered on September 16. Part of the images at September 12-15 are listed at the bottom of this page.
  • In this operation, unlike the previous descent operation using a wide-angle camera, navigation images are acquired using both the narrow angle camera ONC-T and the wide-angle camera ONC-W1. This time, ONC-T images will be mainly delivered.
  • Interval of the images is scheduled about 40 minutes. It may be shifted due to the operation.
  • The page displays the latest list of images at the time of loading. Please reload the browser window to update to the latest image.
  • Time is given in UTC (Universal Time). For Japan time (JST), please add 9 hours. For Eastern Time (ET), please subtract four hours.
  • Delivery will be finished before the lowest point. To know the operation information, please see Twitter (below).

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Target marker separation operation

 

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Image of the first target marker (TM) separation, TM-E!

Separation time: 2019/9/17 at 01:17 JST
Altitude: 1km

This is an overlay of images taken every 4s (for ~1min) as the spacecraft ascends at 11cm/s. TM descent speed is still almost zero. (JAXA, Chiba Inst. Tech & collab)

Quelle: Twitter, JAXA

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From September 12 to September 17, the ‘Target marker separation operation’ will be performed. After that, the ‘Target marker orbit observation operation’ will continue. This is an operation to observe the target marker that goes around Ryugu, and it will be done until the target marker is landed (until about September 23). This operation was rescheduled from September 5 as announced in another article.

These ‘Target marker separation operation’ and ‘Target marker orbit observation operation’ are rehearsals for the separation operation of MINERVA-II2 Rover-2 (University consortium development) scheduled for October.

Figure 1 shows an overview of the operation. The descent starts at a low speed from September 12, and the TM is separated at a surface altitude of 1km from around 0:00 to 2:00 (JST) on September 17. A total of two TMs will be separated. They will be put into the equator and polar orbits around Ryugu, respectively. After that, the spacecraft moves to a position 20km away from Ryugu, with the sun behind. From that position, the optical camera continuously observes the TM trajectory descending around Ryugu. With the sun on the back, the retroreflective film covering the surface of the TMs shines brightly and can be observed. They will be observed until around September 23.

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  • Figure 1 Overview of the target marker separation operation and orbit observation operation
    (Image credit: JAXA)

Figure 2 shows the mounting position of the targer markers. B and A are already separated from the five target markers. This time, E and C will be separated.

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Quelle: JAXA

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Update: 18.09.2019

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Hayabusa 2 completes practice run for deployment of last asteroid lander

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One of two target markers released by Japan’s Hayabusa 2 spacecraft is seen in this overlay image with frames showing the target marker’s location at 4-second intervals. Credit: JAXA

Japan’s Hayabusa 2 spacecraft deployed two target markers Monday above asteroid Ryugu in a rehearsal for the release of the mission’s final landing robot next month.

The robotic asteroid explorer released the two 4-inch (10-centimeter) ball-shaped markers seven minutes apart Monday, after the Hayabusa 2 spacecraft descended to a distance of about 3,300 feet (1 kilometer) from Ryugu.

The Japan Aerospace Exploration Agency, or JAXA, released a pair of images showing the target markers, each covered in a reflective film, after their release from Hayabusa 2. The target markers are unpowered and entirely passive objects designed as navigation aids for Hayabusa 2 around the asteroid.

With both target markers away, Hayabusa 2 fired its thrusters to begin an ascent back to a home position farther from the asteroid. Ground teams are in the final stages of planning another descent toward Ryugu in October, during which Hayabusa 2 will deploy the last of four landing robots to the asteroid’s surface.

“We released two target markers from an altitude of about 1 kilometer, and these images were just released,” said Makoto Yoshikawa, Hayabusa 2’s mission manager at JAXA. “The purpose of this release is a rehearsal of the release of the MINERVA-II-2 small rover next month.”

Hayabusa 2’s cameras will track the movement of the two navigation aids as they fly in space around Ryugu over the next several days. Scientists expect Ryugu’s tenuous gravity will pull the target markers to the asteroid’s surface within a week.

“We can observe the target marker’s orbit around Ryugu and we can then determine the gravity field of Ryugu in detail, so this is a new operation,” Yoshikawa said Tuesday in a press briefing at the European Planetary Science Congress.

Hayabusa 2 is in the final phase of its science campaign at asteroid Ryugu, where it arrived in June 2018 after a three-and-a-half year journey from Earth. The spacecraft has conducted two touch-and-go landings on Ryugu — one in February and another in July — to gather pristine asteroid samples for return to Earth.

Last year, Hayabusa 2 deployed three mobile landers to hop around Ryugu. Two MINERVA-II landers, developed in Japan, and a larger robot named MASCOT managed by the German and French space agencies beamed back images and scientific data from Ryugu’s surface.

One more lander remains in Hayabusa 2’s toolkit.

The MINERVA-II-2 mobile lander was developed by a consortium of Japanese universities as a piggyback payload for Hayabusa 2. The robot is smaller than a soccer ball, but carries mechanisms to allow it to move around the asteroid, along with a camera, a thermometer, photodiode, and an accelerometer.

Hayabusa 2 is scheduled to depart Ryugu by the end of this year using plasma engines, aiming for a return to Earth in December 2020, when the craft will release a parachute-equipped re-entry capsule to land in Australia.

Scientists will retrieve the asteroid specimens for detailed analysis.

“If we have 0.1 grams (of material), we can do all the sample analysis, but we hope we will have much more,” Yoshikawa said.

“We want to study the organic matter on Ryugu because we want to know the origin of life on the Earth, and we think Ryugu has original matter that became life,” he said. “So our main purpose is analysis of the organic matter on the surface of Ryugu.”

Quelle: SN

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Update: 2.10.2019 /20.00 MESZ

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Quelle: JAXA

 

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