Author Topic: LIVE: Hayabusa 2 et al.- H-2A/202 (F-26) Tanegashima - Dec. 3, 2014 (04:22UTC)  (Read 87970 times)

Offline Star One

  • Senior Member
  • *****
  • Posts: 6792
  • UK
  • Liked: 1096
  • Likes Given: 152
Read a report that contact had been lost with PROCYON after the distant Earth flyby?

Offline plutogno

  • Full Member
  • ****
  • Posts: 702
  • Toulouse, France and Milan, Italy
  • Liked: 109
  • Likes Given: 5

Offline yoichi

  • Full Member
  • ****
  • Posts: 495
  • Liked: 149
  • Likes Given: 0
http://global.jaxa.jp/press/2015/12/20151214_hayabusa2.html
Hayabusa2 Earth Swing-by Result
The Hayabusa2 performed the Earth swing-by on the night of December 3 (Thu.), 2015 (Japan Standard Time). The Hayabusa2 flew closest to the Earth at 7:08 p.m. (JST) and passed over the Pacific Ocean near the Hawaii islands at an altitude of about 3,090 km. With the swing-by, the explorer’s orbit turned by about 80 degrees and its speed increased by about 1.6 km per second to about 31.9 km per second (against the sun) thus the orbit achieved the target numbers.
 According to the operation supported by the NASA Deep Space Network stations and European Space Agency deep space ground station, the Hayabusa2 is in good health.

After the swing-by, the Hayabusa2 took images of the Earth using its onboard Optical Navigation Camera - Telescopic (ONC-T). The ONC-T can shoot color images using seven filters.
 The image below is composed by using three of these filters. You can see the Australian continent and Antarctica in the image. The South Pole is not lit by the sun during the summer, and meteorological satellites also do not cover the Antarctic area to take its images, hence the shot this time is precious.

Shot at 1:09 p.m. on Dec. 4 (Japan Standard Time), about 340,000 km from the center of the Earth
 You can see the Australian continent on the upper right, and Antarctica on the lower right.
« Last Edit: 12/14/2015 01:40 AM by yoichi »

Offline perk1329

  • Member
  • Posts: 2
  • Liked: 0
  • Likes Given: 0
after launch a year ago was hayabusa 2 orbiting earth or just traveling in earth's orbit around the sun? thx.

Offline Fuji

  • Full Member
  • ****
  • Posts: 1163
  • Japan
  • Liked: 142
  • Likes Given: 10
after launch a year ago was hayabusa 2 orbiting earth or just traveling in earth's orbit around the sun? thx.

Around the Sun's orbit. See the following fig.
Red orbit is before swing-by. Purple orbit is after the Earth swing-by. 
« Last Edit: 12/18/2015 09:06 PM by Fuji »

Offline perk1329

  • Member
  • Posts: 2
  • Liked: 0
  • Likes Given: 0
thank you fuji. now, hayabusa 2 is traveling at 30.3 km/s and the earth is traveling at 30 km/s (https://en.wikipedia.org/wiki/Earth%27s_orbit). after 12 months hayabusa 2 is 9,460,800 km (30.3 km/s - 30 km/s = 0.3 km/s x 60 s x 60 m x 24 hr x 365 d) past earth. how did hayabusa 2 get to 3090 km from earth for the gravity assist?

Offline Fuji

  • Full Member
  • ****
  • Posts: 1163
  • Japan
  • Liked: 142
  • Likes Given: 10
how did hayabusa 2 get to 3090 km from earth for the gravity assist?

Media briefing document for Earth swing-by result.
http://fanfun.jaxa.jp/jaxatv/files/20151224_hayabusa2.pdf

-Sep 1-2  IES-TCM   1.3m/sec by 12 hors ion engine burn.  Navigation error reduced 10,000km to 400km.
-Nov.3  TCM1 23cm/sec by 3.95sec RCS burn. Navigation error reduced 400km to 11km.
-Nov.26 TCM2 4.6cm/sec by 0.8sec RCS burn. Navigation error reduced 11km to 3km.

Final navigation accuracy was 300m (Planed target is red dot at attached fig. blue dot is real pass point).

Offline yoichi

  • Full Member
  • ****
  • Posts: 495
  • Liked: 149
  • Likes Given: 0
Hayabusa2 remoto Sensing Instruments


Offline jacqmans

  • Moderator
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 16243
  • Houten, The Netherlands
  • Liked: 2239
  • Likes Given: 130
Press release, 14 July 2016

Health check for asteroid lander MASCOT

Space travel is no easy task – first comes the stressful launch with vibrations, then the long flight through the bitter cold and the vacuum. The Mobile Asteroid Surface Scout (MASCOT) has been travelling
on board the Japanese Hayabusa2 spacecraft for the last one-and-a-half years, and is currently at approximately 65 million kilometres from Earth. On 14 July 2016, the German Aerospace Center (Deutsches
Zentrum fuer Luft- und Raumfahrt; DLR) engineers in the Lander Control Center (LCC) in Cologne switched the shoebox-sized lander and its four German and French-built instruments back on, and will spend
the next few days finding answers to two questions: How is MASCOT's state of health? And how are the experiments on board? "We do a check-up once a year to find out whether all system components and instruments
are still in good working order," explains Christian Krause from the Lander Control Center team at DLR. 

A complete package for a primitive object

The Hayabusa2 spacecraft by the Japanese space agency JAXA set off on its mission on 3 December 2014, carrying the French-German MASCOT lander. One year later, the duo zipped round the Earth to gain momentum
and sent back photos from our planet before continuing on toward the asteroid Ryugu. The spacecraft will venture deeper into space until the summer of 2018, when it will enter orbit around the celestial
body that DLR planetary researcher Ralf Jaumann refers to as a 'beautifully primitive object'. "During this mission, we will be investigating primordial material from the solar nebula; it has remained practically
unchanged in its 4.5 billion years of existence." Then, while the Hayabusa2 spacecraft measures and analyses the asteroid from its position in orbit, MASCOT will descend to its surface to conduct scientific
measurements. The Japanese spacecraft will also take on soil samples that it will bring back to Earth in 2020. "This is a complete package. There has never been anything like this before: we will be observing
and mapping remotely, measuring the asteroid, analysing its surface and bringing the samples back to Earth." But this complete package requires the concerted efforts of engineers and scientists from Germany,
France and Japan who have joined forces in an international cooperation.

Like the dwarf planet Ceres, the asteroid that the scientists have targeted – Ryugu – belongs to the C class of carbon-rich asteroids. Observations from Earth suggest that water could be bound in the asteroid's
regolith . In addition, the celestial body, named after a submerged palace described in Japanese mythology, belongs to the Apollo group of asteroids that cross Earth's orbit. Even though Ryugu will never
pose a risk to Earth, learning more about this type of asteroid will be helpful to prepare for future defence missions. Hayabusa2 and MASCOT will cooperate as a team on this mission: Hayabusa2 will deliver
the data to locate a suitable landing site for MASCOT. Then the lander will analyse the asteroid's surface and send information and data on the location of the soil samples that Hayabusa2 will eventually
bring back to Earth.

Training for independence

The team at the DLR Microgravity User Support Center (MUSC) are training with a ground model of the lander to ensure that everything runs like clockwork. "Once on the ground, MASCOT will have to operate
its four instruments as autonomously as possible," explains Christian Krause from the DLR Mascot Control Center. The vast distance from Earth simply does not permit control in real time, so the engineers
must program software that the lander will need as 'knowledge' on its mission. In total, four instruments are fitted to the interior of the lander, which measures 30 by 30 by 20 centimetres. The instruments
include a DLR radiometer and a camera, a French spectrometer and a magnetometer by TU Braunschweig. Together they are designed to analyse the mineralogical and geological composition of the asteroid surface
and to measure its surface temperature and magnetic field.

After landing, MASCOT will deploy its sensors to ascertain whether it is standing upright on the asteroid surface, or whether it has ended up on its side. An internal swing arm can then automatically provide
the right impulse to restore MASCOT to its correct position. After conducting the first measurements, the lander will use the swing arm to hop to the next measurement point. "We are planning as well as
we can, although we know that we must expect the unexpected," says Christian Krause from DLR. Ryugu has a diameter of approximately 900 metres, and it only possesses around 1/60,000th of the Earth's gravitational
field. One day lasts rapproximately 7.6 hours. But these values were measured from Earth, and the MASCOT team will have to wait until Hayabusa2 enters orbit around Ryugu to find out whether and how much
their estimates deviate from reality.

Heat, measure, transmit

But first of all, the MASCOT team will put the lander through its paces until 16 July 2016. To do this, the team heated the lander back up to operating temperature following its lengthy travel through space
at around -30 degrees Celsius. After switching the lander on, the first step will be to upload the correct command sequences for MASCOT to perform its health check. Even now, two years before arrival, each
signal takes three minutes to travel in one direction. Therefore, the team at the LCC will have to wait approximately seven minutes after sending a message to MASCOT before they can expect a response.

In addition to the data that MASCOT will be asked to send on its own state of health, the engineers and scientists on the ground will also assess how well the four instruments are working and whether they
show changes in parameters after their journey so far. Light-emitting diodes will be switched on, a photograph taken, and the swing arm carefully set in motion. "We cannot leave all this equipment unused
for years. It needs to be activated repeatedly until it is time to land," emphasises Krause. "We also plan to test the interaction between the Hayabusa2 orbiter and the lander to make sure that everything
is prepared for the science phase on the asteroid. When that time comes, MASCOT's data will be beamed via the orbiter to the Japanese Control Center and from there to its counterpart at DLR.

The team at the DLR MASCOT Control Center will make contact with its lander on several occasions before the mission reaches its culmination in October 2018. They will occasionally check the lander's state
of health, as well as calibrate the instruments to ensure that the data can be analysed accurately after landing. The Control Room team around Krause has their eyes fixed firmly on the objective for the
coming two years: "We only want to intervene after landing if something goes wrong – otherwise MASCOT will simply proceed autonomously with its scientific programme, without our help," says Tra-Mi Ho, Mascot
Project Manager at the DLR Institute of Space Systems.

DLR's participation in the Hayabusa2 mission

The DLR Institute of Space Systems developed the lander and tested it under space conditions during parabolic flights, in a drop tower, on a shaker and in a thermal vacuum chamber. The DLR Institute of
Composite Structures and Adaptive Systems was responsible for the stable structure of the lander. The DLR Institute of Robotics and Mechatronics developed the swing arm that MASCOT will use to 'hop' on
the asteroid. The DLR Institute of Planetary Research managed the development of the MASCAM camera and the MARA radiometer. The asteroid lander is being monitored and controlled from the Microgravity User
Support Center (MUSC) in Cologne.

Offline plutogno

  • Full Member
  • ****
  • Posts: 702
  • Toulouse, France and Milan, Italy
  • Liked: 109
  • Likes Given: 5
open access paper: Laser link experiment with the Hayabusa2 laser altimeter for in-flight alignment measurement

Quote
We report results of a laser link experiment between a laser altimeter called light detection and ranging (LIDAR) aboard Hayabusa2 and ground-based satellite laser ranging stations conducted when the spacecraft was near the Earth before and after the gravity assist operation. Uplink laser pulses from a ground station were successfully detected at a distance of 6.6 million km, and the field of view direction of the receiving telescope of the LIDAR was determined in the spacecraft frame. The intensities of the received signals were measured, and the link budget from the ground to the LIDAR was confirmed. By detecting two successive pulses, the pulse intervals from the ground-based station were transferred to the LIDAR, and the clock frequency offset was thus successfully calibrated based on the pulse intervals. The laser link experiment, which includes alignment measurement of the telescopes, has proven to be an excellent method to confirm the performance of laser altimeters before they arrive at their target bodies, especially for deep space missions.

https://earth-planets-space.springeropen.com/articles/10.1186/s40623-016-0589-8

Offline Fuji

  • Full Member
  • ****
  • Posts: 1163
  • Japan
  • Liked: 142
  • Likes Given: 10
Micro spacecraft investigates cometary water mystery   January 24, 2017 NAOJ
http://www.nao.ac.jp/en/news/science/2017/20170124-procyon.html
Quote
Abstract

In September 2015, a team of astronomers from the National Astronomical Observatory of Japan, University of Michigan, Kyoto Sangyo University, Rikkyo University and the University of Tokyo successfully observed the entire hydrogen coma of the comet 67P/Churyumov-Gerasimenko, using the LAICA telescope onboard the PROCYON spacecraft. They also succeeded in obtaining the absolute rate of water discharge from the comet.

This comet was the target of ESA’s Rosetta mission in 2015. Because the Rosetta spacecraft was actually inside the cometary coma, it couldn’t observe the overall coma structure. There were bad observing conditions during the time the comet could be observed from Earth, so through our observations, we were able to test the coma models for the comet for the first time.

Comet observation by the PROCYON spacecraft had not been scheduled in the original mission plan. Thanks to the efforts of the spacecraft and telescope operation teams, observations were conducted shortly after we started discussing the possibility, producing results of great scientific importance.

This result is the first scientific achievement by a micro spacecraft for deep space exploration. Moreover, this provides an ideal example where observations by a low-cost mission (e.g., the PROCYON mission) support precise observations by a large mission (e.g., the Rosetta mission). We hope this will become a model case for micro spacecraft observations in support of large missions.

This result was published in the Astronomical Journal on January 24, 2017 at 12:00 am EST.

Tags: