Hayabusa2

Summary

Hayabusa2 (Japanese: はやぶさ2, lit.'Peregrine falcon 2') is an asteroid sample-return mission operated by the Japanese state space agency JAXA. It is a successor to the Hayabusa mission, which returned asteroid samples for the first time in June 2010.[10] Hayabusa2 was launched on 3 December 2014 and rendezvoused in space with near-Earth asteroid 162173 Ryugu on 27 June 2018.[11] It surveyed the asteroid for a year and a half and took samples. It left the asteroid in November 2019 and returned the samples to Earth on 5 December 2020 UTC.[8][12][13] Its mission has now been extended through at least 2031, when it will rendezvous with the small, rapidly-rotating asteroid 1998 KY26.

Hayabusa2
Artist's impression of Hayabusa2 firing its ion thrusters
Mission typeAsteroid sample-return
OperatorJAXA
COSPAR ID2014-076A Edit this at Wikidata
SATCAT no.40319
Websitewww.hayabusa2.jaxa.jp/en/
Mission duration6 years (planned)
(9 years, 3 months and 24 days elapsed)
Spacecraft properties
Spacecraft typeHayabusa
ManufacturerNEC[1]
Launch mass600 kg[2]
Dry mass490 kg (1,080 lb) [3]
DimensionsSpacecraft bus: 1 × 1.6 × 1.25 m (3 ft 3 in × 5 ft 3 in × 4 ft 1 in)
Solar panel: 6 m × 4.23 m (19.7 ft × 13.9 ft)
Power2.6 kW (at 1 au), 1.4 kW (at 1.4 au)
Start of mission
Launch date3 December 2014,
04:22:04 UTC[4]
RocketH-IIA 202
Launch siteTanegashima Space Center, LA-Y
ContractorMitsubishi Heavy Industries
End of mission
Landing dateRe-entry capsule:
5 December 2020 UTC [5]
Landing siteWoomera, Australia
Flyby of Earth
Closest approach3 December 2015
Distance3,090 km (1,920 mi) [6]
Rendezvous with (162173) Ryugu
Arrival date27 June 2018, 09:35 UTC [7]
Departure date12 November 2019 [8]
Sample mass5.4 grams[9](including gas samples)
(162173) Ryugu lander
Landing date21 February 2019
(162173) Ryugu lander
Landing date11 July 2019
Flyby of Earth (Sample return)
Closest approach5 December 2020 UTC [5]
 

Hayabusa2 carries multiple science payloads for remote sensing and sampling, and four small rovers to investigate the asteroid surface and analyze the environmental and geological context of the samples collected.

Mission overview edit

Hayabusa2 mission overview animation
 
Animation of Hayabusa2 orbit from 3 December 2014
  Hayabusa2   162173 Ryugu   Earth   Sun
See detailed video including the extended mission

Asteroid 162173 Ryugu (formerly designated 1999 JU3) is a primitive carbonaceous near-Earth asteroid. Carbonaceous asteroids are thought to preserve the most pristine, untainted materials in the Solar System, a mixture of minerals, ice, and organic compounds that interact with each other.[14] Studying it is expected to provide additional knowledge on the origin and evolution of the inner planets and, in particular, the origin of water and organic compounds on Earth,[14][15] all relevant to the origin of life on Earth.[16]

Initially, launch was planned for 30 November 2014,[17][18][19] but was delayed to 3 December 2014 at 04:22:04 UTC (3 December 2014, 13:22:04 local time) on a H-IIA launch vehicle.[20] Hayabusa2 launched together with PROCYON asteroid flyby space probe. PROCYON's mission was a failure. Hayabusa2 arrived at Ryugu on 27 June 2018,[11] where it surveyed the asteroid for a year and a half and collected samples.[14] It departed the asteroid in November 2019 and returned the samples to Earth in December 2020.[19]

Compared to the previous Hayabusa mission, the spacecraft features improved ion engines, guidance and navigation technology, antennas, and attitude control systems.[21] A kinetic penetrator (a high-explosive shaped charge) was shot into the asteroid surface to expose pristine sample material which was later collected for return to Earth.[15][19]

Funding and history edit

Following the initial success of Hayabusa, JAXA began studying a potential successor mission in 2007.[22] In July 2009, Makoto Yoshikawa of JAXA presented a proposal titled "Hayabusa Follow-on Asteroid Sample Return Missions". In August 2010, JAXA obtained approval from the Japanese government to begin development of Hayabusa2. The cost of the project estimated in 2010 was 16.4 billion yen (US$149 million).[10][23]

Hayabusa2 was launched on 3 December 2014, arrived at asteroid Ryugu on 27 June 2018, and remained stationary at a distance of about 20 km (12 mi) to study and map the asteroid. In the week of 16 July 2018, commands were sent to move to a lower hovering altitude.[24]

On 21 September 2018, the Hayabusa2 spacecraft ejected the first two rovers, Rover-1A (HIBOU)[25] and Rover-1B (OWL), from about a 55 m (180 ft) altitude that dropped independently to the surface of the asteroid.[26][27] They functioned nominally and transmitted data.[28] The MASCOT rover deployed successfully on 3 October 2018 and operated for about 16 hours as planned.[29]

The first sample collection was scheduled to start in late October 2018, but the rovers encountered a landscape with large and small boulders but no surface soil for sampling. Therefore, it was decided to postpone the sample collection plans to 2019 and further evaluate various options for the landing.[30][31] The first surface sample retrieval took place on 21 February 2019. On 5 April 2019, Hayabusa2 released an impactor to create an artificial crater on the asteroid surface. However, Hayabusa2 initially failed on 14 May 2019 to drop special reflective markers necessary onto the surface for guiding the descent and sampling processes,[32] but later it successfully dropped one from an altitude of 9 m (30 ft) on 4 June 2019.[33] The sub-surface sampling took place on 11 July 2019.[34] The spacecraft departed the asteroid on 13 November 2019 (with departure command sent at 01:05 UTC on 13 November 2019). It successfully delivered the samples back to Earth on 6 December 2020 (JST), dropping the contents by parachute in a special container at a location in southern Australia. The samples were retrieved the same day for secure transport back to the JAXA labs in Japan.[8][35][36]

Spacecraft edit

Hayabusa2 Performance[37][38]
Propulsion
Number of thrusters
4 (one is a spare)
Total thrust (ion drive)
28 mN
Specific impulse (Isp)
3000 seconds
Acceleration
49 μm/s2
Power
1250 W
Spacecraft wet mass
600 kg
Ion engine system
dry mass
66 kg
Ion engine system
wet mass
155 kg
Solar array
23 kg
Xenon propellant
66 kg
Hydrazine/MON-3 propellant
48 kg
Thrust (chemical propellants)
20 N

The design of Hayabusa2 is based on the first Hayabusa spacecraft, with some improvements.[14][39] It has a mass of 600 kilograms (1,300 lb) including fuel,[39] and electric power is generated by two sets of solar arrays with an output of 2.6 kW at 1 AU, and 1.4 kW at 1.4 AU.[39] The power is stored in eleven inline-mounted 13.2 Ah lithium-ion batteries.[39]

Propulsion

The spacecraft features four solar-electric ion thrusters for propulsion called μ10,[37] one of which is a backup. These engines use microwaves to convert xenon into plasma (ions), which are accelerated by a voltage applied by the solar panels and ejected out the back of the engine. The simultaneous operation of three engines generates thrusts of up to 28 mN.[39] Although this thrust is very small, the engines are also extremely efficient; the 66 kg (146 lb) of xenon[37] reaction mass can change the speed of the spacecraft by up to 2 km/s.[39]

The spacecraft has four redundant reaction wheels and a chemical reaction control system featuring twelve thrusters for attitude control (orientation) and orbital control at the asteroid.[37][39] The chemical thrusters use hydrazine and MON-3, with a total mass of 48 kg (106 lb) of chemical propellant.[39]

Communication

The primary contractor NEC built the 590 kg (1,300 lb) spacecraft, its Ka-band communications system and a mid-infrared camera.[21] The spacecraft has two high-gain directional antennas for X-band and Ka-band.[37] Bit rates are 8 bit/s to 32 kbit/s.[39] The ground stations are the Usuda Deep Space Center, Uchinoura Space Center, NASA Deep Space Network and Malargüe Station (ESA).[39]

Navigation

The optical navigation camera telescope (ONC-T) is a telescopic framing camera with seven colors to optically navigate the spacecraft.[40] It works in synergy with the optical navigation camera wide-field (ONC-W2) and with two star trackers.[39]

In order to descend to the asteroid surface to perform sampling, the spacecraft released one of five target markers in the selected landing zones as artificial guide marks, with highly reflective outer material that is recognized by a strobe light mounted on the spacecraft.[39] The spacecraft also used its laser altimeter and ranging (LIDAR) as well as Ground Control Point Navigation (GCP-NAV) sensors during sampling.[39]

Firsts edit

The Hayabusa2 spacecraft was the first to deploy operating rovers on an asteroid.

Science payload edit

 
Hayabusa2 instrument inventory

The Hayabusa2 payload is equipped with multiple scientific instruments:[39][41]

  • Remote sensing: Optical Navigation Camera (ONC-T, ONC-W1, ONC-W2), Near-Infrared Camera (NIR3), Thermal-Infrared Camera (TIR), Light Detection And Ranging (LIDAR)
  • Sampling: Sampling device (SMP), Small Carry-on Impactor (SCI), Deployable Camera (DCAM3)
  • Four rovers: Mobile Asteroid Surface Scout (MASCOT), Rover-1A, Rover-1B, Rover-2.

Remote sensing edit

The Optical Navigation Cameras (ONCs) were used for spacecraft navigation during the asteroid approach and proximity operations. They also remotely imaged the surface to search for interplanetary dust around the asteroid. ONC-T is a telephoto camera with a 6.35° × 6.35° field of view and several optical filters carried in a carousel. ONC-W1 and ONC-W2 are wide angle (65.24° × 65.24°) panchromatic (485–655 nm) cameras with nadir and oblique views, respectively.[39]

The Near-Infrared Spectrometer (NIRS3) is a spectrograph operating at a wavelength of 1.8–3.2 μm. NIRS3 was used for analysis of surface mineral composition.[39]

The Thermal-Infrared Imager (TIR) is a thermal infrared camera working at 8–12 μm, using a two-dimensional microbolometer array. Its spatial resolution is 20 m at 20 km distance or 5 cm at 50 m distance (70 ft at 12 mi, or 2 in at 160 ft). It was used to determine surface temperatures in the range −40 to 150 °C (−40 to 302 °F).[39]

The Light Detection And Ranging (LIDAR) instrument measured the distance from the spacecraft to the asteroid surface by measuring the reflected laser light. It operated over an altitude range between 30 m and 25 km (100 ft and 16 mi).[39]

When the spacecraft was closer to the surface than 30 m (98 ft) during the sampling operation, the Laser Range Finders (LRF-S1, LRF-S3) were used to measure the distance and the attitude (orientation) of the spacecraft relative to the terrain.[42][43] The LRF-S2 monitored the sampling horn to trigger the sampling projectile.

LIDAR and ONC data are being combined to determine the detailed topography (dimensions and shape) of the asteroid. Monitoring of a radio signal from Earth allowed measurement of the asteroid's gravitational field.[39]

Rovers edit

Hayabusa2 carried four small rovers to explore the asteroid surface in situ,[44] and provide context information for the returned samples. Due to the minimal gravity of the asteroid, all four rovers were designed to move around by short hops instead of using normal wheels. They were deployed at different dates from about 60 m (200 ft) altitude and fell freely to the surface under the asteroid's weak gravity.[45] The first two rovers, called HIBOU (previously Rover-1A) and OWL (previously Rover-1B), landed on asteroid Ryugu on 21 September 2018.[28] The third rover, called MASCOT, was deployed 3 October 2018. Its mission was successful.[46] The fourth rover, known as Rover-2 or MINERVA-II-2, failed before release from the orbiter. It was released on 2 October 2019 to orbit the asteroid and perform gravitational measurements before being allowed to impact the asteroid a few days later.

MINERVA-II edit

 
The first photograph from the surface of an asteroid, taken by HIBOU on 22 September 2018 during one of its "hops".

MINERVA-II is a successor to the MINERVA lander carried by Hayabusa. It consists of two containers with 3 rovers.

MINERVA-II-1 is a container that deployed two rovers, Rover-1A (HIBOU) and Rover-1B (OWL), on 21 September 2018.[47][48] It was developed by JAXA and the University of Aizu. The rovers are identical having a cylindrical shape, 18 cm (7.1 in) diameter and 7 cm (2.8 in) tall, and a mass of 1.1 kg (2.4 lb) each.[39][49] They move by hopping in the low gravitational field, using a torque generated by rotating masses within the rovers.[50] Their scientific payload is a stereo camera, wide-angle camera, and thermometers. Solar cells and double-layer capacitors provide the electrical power.[2][51] The MINERVA-II-1 rovers were successfully deployed 21 September 2018. Both rovers performed successfully on the asteroid surface, sending images and video from the surface. Rover-1A operated for 113 asteroid days (36 Earth days) returning 609 images from the surface, and Rover-1B operated for 10 asteroid days (3 Earth days) returning 39 images from the surface.[52]

The MINERVA-II-2 container held the ROVER-2 (sometimes referred to as MINERVA-II-2), developed by a consortium of universities led by Tohoku University in Japan. This was an octagonal prism shape, 15 cm (5.9 in) diameter and 16 cm (6.3 in) tall, with a mass of about 1 kg (2.2 lb). It had two cameras, a thermometer and an accelerometer. It was equipped with optical and ultraviolet LEDs to illuminate and detect floating dust particles. ROVER-2 carried four mechanisms to move around using short hops.[2] Rover-2 had problems prior to deployment from the orbiter but was released on 2 October 2019 to orbit the asteroid and perform gravitational measurements. It was then crashed onto the asteroid surface a few days later on 8 October 2019.

MASCOT edit

 
Mission overview

The Mobile Asteroid Surface Scout (MASCOT) was developed by the German Aerospace Center (DLR) in cooperation with the French space agency CNES.[53] It measures 29.5 cm × 27.5 cm × 19.5 cm (11.6 in × 10.8 in × 7.7 in) and has a mass of 9.6 kg (21 lb).[54] MASCOT carries four instruments: an infrared spectrometer (MicrOmega), a magnetometer (MASMAG), a radiometer (MARA), and a camera (MASCAM) that imaged the small-scale structure, distribution and texture of the regolith.[55] The rover is capable of tumbling once to reposition itself for further measurements.[44][56] It collected data on the surface structure and mineralogical composition, the thermal behaviour and the magnetic properties of the asteroid.[57] It has a non-rechargeable battery that allowed for operations for approximately 16 hours.[58][59] The infrared radiometer on the InSight Mars lander, launched in 2018, is based on the MASCOT radiometer.[60][61]

MASCOT was deployed 3 October 2018. It had a successful landing and performed its surface mission successfully. Two papers were published describing the results from MASCOT in the scientific journals Nature Astronomy[62] and Science.[63] One finding of the research was that C-type asteroids consist of more porous material than previously thought, explaining a deficit of this meteorite type. Meteorites of this type are too porous to survive the entry into the atmosphere of planet Earth. Another finding was that Ryugu consists of two different almost black types of rock with little internal cohesion, but no dust was detected.[64][65] A third paper describing results from MASCOT was published in the Journal of Geophysical Research and describes the magnetic properties of Ryugu, showing that Ryugu does not have a magnetic field on a boulder scale.[66]

Objects deployed by Hayabusa2 edit

Object Developed by Mass Dimensions Power Science payload Landing or deployed date Status
MINERVA-II-1 rovers:
Rover-1A (HIBOU)
Rover-1B (OWL)
JAXA and University of Aizu 1.1 kg (2.4 lb) each Diameter: 18 cm (7.1 in)
Height: 7 cm (2.8 in)
Solar panels Wide-angle camera, stereo camera, thermometers
21 September 2018
Successful landing. Rover-1A operated for 36 days and Rover-1B operated for 3 days.[52]
Rover-2 (MINERVA-II-2) Tohoku University 1.0 kg (2.2 lb) Diameter: 15 cm (5.9 in)
Height: 16 cm (6.3 in)
Solar panels Two cameras, thermometer, accelerometer. Optical and ultraviolet LEDs for illumination
Released: 2 October 2019, 16:38 UTC
Rover failed before deployment, so it was released in orbit around the asteroid to perform gravitational measurements before it impacted a few days later.[67][68]
MASCOT German Aerospace Center and CNES 9.6 kg (21 lb) 29.5 cm × 27.5 cm × 19.5 cm (11.6 in × 10.8 in × 7.7 in) Non-rechargeable
battery[58]
Camera, infrared spectrometer, magnetometer, radiometer
3 October 2018[69]
Successful landing. Operated on battery for more than 17 hours[59]
Deployable camera 3 (DCAM3)
JAXA
about 2 kg (4.4 lb) Diameter: 7.8 cm (3.1 in)
Height: 7.8 cm (3.1 in)
Non-rechargeable battery DCAM3-A lens, DCAM3-D lens
5 April 2019
Deployed to observe impact of SCI impactor. Inactive now and presumed to have fallen on the asteroid.
Small Carry-On Impactor (SCI)
JAXA
2.5 kg (5.5 lb) Diameter: 30 cm (12 in)
Height: 21.7 cm (8.5 in)
Non-rechargeable battery
None
5 April 2019
Successful. Shot to the surface 40 minutes after separation.
Target Marker B
JAXA
300 g (11 oz) 10 cm (3.9 in) sphere
None
None
25 October 2018
Successful. Used for first touchdown.
Target Marker A
JAXA
300 g (11 oz) 10 cm (3.9 in) sphere
None
None
30 May 2019
Successful. Used for second touchdown.
Target Marker E (Explorer)
JAXA
300 g (11 oz) 10 cm (3.9 in) sphere
None
None
17 September 2019
Successful. Injected to equatorial orbit and confirmed to land.
Target Marker C (Sputnik/Спутник)
JAXA
300 g (11 oz) 10 cm (3.9 in) sphere
None
None
17 September 2019
Successful. Injected to polar orbit and confirmed to land.
Target Marker D
JAXA
300 g (11 oz) 10 cm (3.9 in) sphere
None
None
Was not deployed.
Sample Return Capsule
JAXA
16 kg Diameter: 40 cm Height: 20 cm Non-rechargeable battery Sample container, Reentry flight Environment Measurement Module
5 December 2020 UTC
Successful landing. All the parts including the sample container were collected.

Sampling edit

Sampling Date
1st surface sampling 21 February 2019
Sub-surface sampling SCI impactor: 5 April 2019
Target marker: 5 June 2019[33]
Sampling: 11 July 2019[34]
2nd surface sampling Optional;[70] was not done.
 
Artistic rendering of Hayabusa collecting a surface sample.

The original plan was for the spacecraft to collect up to three samples: 1) surface material that exhibits traits of hydrous minerals; 2) surface material with either unobservable or weak evidence of aqueous alterations; 3) excavated sub-surface material.[71]

The first two surface samples were scheduled to start in late October 2018, but the rovers showed large and small boulders and insufficient surface area to sample, so the mission team decided to postpone sampling to 2019 and evaluate various options.[30] The first surface sampling was completed on 22 February 2019 and obtained a substantial amount of topsoil,[70][72] so the second surface sampling was postponed and was eventually cancelled to decrease the risks to the mission.[70]

The second and final sample was collected from material that was dislodged from beneath the surface by the kinetic impactor (SCI impactor) shot from a distance of 300 m (980 ft).[73][74] All samples are stored in separate sealed containers inside the sample return capsule (SRC).

Surface sample edit

Hayabusa2's sampling device is based on Hayabusa's. The first surface sample retrieval was conducted on 21 February 2019, which began with the spacecraft's descent, approaching the surface of the asteroid. When the sampler horn attached to Hayabusa2's underside touched the surface, a 5 g (0.18 oz) tantalum projectile (bullet) was fired at 300 m/s (980 ft/s) into the surface.[72] The resulting ejected materials were collected by a "catcher" at the top of the horn, which the ejecta reached under their own momentum under microgravity conditions.[75]

Sub-surface sample edit

 
Animation illustrating SCI deployment and subsequent sampling from the resulting crater.

The sub-surface sample collection required an impactor to create a crater in order to retrieve material under the surface, not subjected to space weathering. This required removing a large volume of surface material with a powerful impactor. For this purpose, Hayabusa2 deployed on 5 April 2019 a free-flying gun with one "bullet", called the Small Carry-on Impactor (SCI); the system contained a 2.5 kg (5.5 lb) copper projectile, shot onto the surface with an explosive propellant charge. Following SCI deployment, Hayabusa2 also left behind a deployable camera (DCAM3)[Note 1] to observe and map the precise location of the SCI impact, while the orbiter maneuvered to the far side of the asteroid to avoid being hit by debris from the impact.

It was expected that the SCI deployment would induce seismic shaking of the asteroid, a process considered important in the resurfacing of small airless bodies. However, post-impact images from the spacecraft revealed that little shaking had occurred, indicating the asteroid was significantly less cohesive than was expected.[76]

The touchdown on and sampling of Ryugu on 11 July

Approximately 40 minutes after separation, when the spacecraft was at a safe distance, the impactor was fired into the asteroid surface by detonating a 4.5 kg (9.9 lb) shaped charge of plasticized HMX for acceleration.[56][77] The copper impactor was shot onto the surface from an altitude of about 500 m (1,600 ft) and it excavated a crater of about 10 m (33 ft) in diameter, exposing pristine material.[15][32] The next step was the deployment on 4 June 2019 of a reflective target marker in the area near the crater to assist with navigation and descent.[33] The touchdown and sampling took place on 11 July 2019.[34]

Sample return edit

 
Replica of Hayabusa's sample-return capsule (SRC) used for re-entry. Hayabusa2's capsule is of the same size, measuring 40 cm (16 in) in diameter and using a parachute for touchdown.

The spacecraft collected and stored the samples in separate sealed containers inside the sample-return capsule (SRC), which is equipped with thermal insulation. The container is 40 cm (16 in) external diameter, 20 cm (7.9 in) in height, and a mass of about 16 kg (35 lb).[39]

At the end of the science phase in November 2019,[8] Hayabusa2 used its ion engines for changing orbit and return to Earth.[75] Hours before Hayabusa2 flew past Earth in late 2020, it released the capsule, on 5 December 2020 at 05:30 UTC.[78] The capsule was released spinning at one revolution per three seconds. The capsule re-entered the Earth's atmosphere at 12 km/s (7.5 mi/s) and it deployed a radar-reflective parachute at an altitude of about 10 km (6.2 mi), and ejected its heat-shield, while transmitting a position beacon signal.[39][75] The sample capsule landed at the Woomera Test Range in Australia.[13][79] The total flight distance was 5.24×10^9 km (35.0 AU).[39]

Any volatile substances will be collected before the sealed containers are opened.[71] The samples will be curated and analyzed at JAXA's Extraterrestrial Sample Curation Center,[80] where international scientists can request a small portion of the samples. The spacecraft brought back a capsule containing carbon-rich asteroid fragments that scientists believe could provide clues about the ancient delivery of water and organic molecules to Earth.[81][82]

 
One of the facility-to-facility transfer containers (FFTC) of Hayabusa2 returned samples given to NASA by JAXA.

JAXA is sharing a portion of these samples with NASA, and in exchange, NASA will provide JAXA a percentage of a sample of asteroid Bennu, when the agency's OSIRIS-REx spacecraft returned to Earth from the space rock on 9/24/2023.[83]

Mission extension (Hayabusa2♯) edit

Animation of Hayabusa2 orbit – extended mission
  Hayabusa2 ·   162173 Ryugu ·   Earth ·   Sun ·   2001 CC21 ·   1998 KY26

With the successful return and retrieval of the sample capsule on 6 December 2020 (JST), Hayabusa2 will now use its remaining 30 kg (66 lb) of xenon propellant (from the initial 66 kg (146 lb)) to extend its service life and fly out to explore new targets.[84] As of September 2020, a fly-by of (98943) 2001 CC21[85] in July 2026 and a rendezvous with 1998 KY26 in July 2031 were selected for the mission extension.[86][87][88] The observation of 2001 CC21 will be a high-speed fly-by of the L-type asteroid, a relatively uncommon type of asteroid.[89] The fixed camera of Hayabusa2 was not designed for this type of fly-by. The rendezvous with 1998 KY26 will be the first visit of a fast rotating micro-asteroid, with a rotation period of about 10 minutes.[88] Between 2021 and 2026, the spacecraft will also conduct observations of exoplanets.[90] An option to conduct a Venus flyby to set up an encounter with 2001 AV43 was also studied.[91][92]

Selected EAEEA (Earth → Asteroid → Earth → Earth → Asteroid) scenario:[88]

  • December 2020: Extension mission start
  • 2021 until July 2026: cruise operation
  • July 2026: L-type asteroid 2001 CC21 high-speed fly-by
  • December 2027: Earth swing-by
  • June 2028: Second Earth swing-by
  • July 2031: Target body (1998 KY26) rendezvous

The nickname of the Extended Mission is “Hayabusa2♯” (read “Hayabusa2 Sharp”). The character “♯” is a musical symbol that means “raise the note by a semitone”, and for this mission, it is also the acronym for “Small Hazardous Asteroid Reconnaissance Probe”. This name indicates that the Hayabusa2 Extended Mission is set to investigate small but potentially dangerous asteroids that may collide with the Earth in the future. The English meaning of the word “sharp” also highlights the extremely challenging nature of this mission, which is also reflected in the musical meaning of “raise the note by a semitone”, suggestive of raising of the rank of the mission. As the character “♯” is a musical symbol, it can be difficult to enter in practice when typing. The symbol can therefore be substituted for the “#” symbol (number sign / pound / hash) that is on computer keyboards or phones. There is no problem with the notation “Hayabusa2♯” (musical symbol) or “Hayabusa2#”.[93][94]

See also edit

Japanese minor body probes edit

Notes edit

  1. ^ DCAM3 is numbered as such because it is a follow-on to the DCAM1 and DCAM2 used for the IKAROS interplanetary solar sail

References edit

  1. ^ "JAXA Launches Hayabusa 2 Asteroid Probe". nec.com (Press release). NEC. 3 December 2014. Tokyo. Archived from the original on 18 April 2022.
  2. ^ a b c "Display: Hayabusa2 2014-076A". NASA. 14 May 2020. 2014-076A. Archived from the original on 8 June 2023. Retrieved 27 January 2021.   This article incorporates text from this source, which is in the public domain.
  3. ^ "Hayabusa-2 – Asteroid Exploration Mission". Archived from the original on 29 October 2023. Retrieved 30 June 2019.
  4. ^ "Launch of "Hayabusa2" by H-IIA Launch Vehicle No. 26" (Press release). JAXA & Mitsubishi Heavy Industries. 30 September 2014. Archived from the original on 28 October 2023.
  5. ^ a b "Joint Statement for Cooperation in the Hayabusa2 Sample Return Mission by the Australian Space Agency and the Japan Aerospace Exploration Agency" (Press release). JAXA & the Australian Space Agency. 14 July 2020. Archived from the original on 1 January 2024. Retrieved 14 July 2020.
  6. ^ "Hayabusa2 Earth Swing – by Result" (Press release). JAXA & National Research and Development Agency. 14 December 2015. Archived from the original on 28 October 2023.
  7. ^ "Arrival at Ryugu!". JAXA Hayabusa2 Project. 29 June 2018. Archived from the original on 29 May 2023. Retrieved 15 July 2018.
  8. ^ a b c d Bartels, Meghan (13 November 2019). "Farewell, Ryugu! Japan's Hayabusa2 Probe Leaves Asteroid for Journey Home". Space.com. Archived from the original on 24 October 2023.
  9. ^ "Hayabusa2 returned with 5 grams of asteroid soil, far more than target". The Japan Times. Kyodo News. Archived from the original on 1 October 2023.
  10. ^ a b Wendy Zukerman (18 August 2010). "Hayabusa2 will seek the origins of life in space". New Scientist. Retrieved 17 November 2010.
  11. ^ a b Clark, Stephen (28 June 2018). "Japanese spacecraft reaches asteroid after three-and-a-half-year journey". Spaceflight Now. Archived from the original on 24 October 2023. Retrieved 2 July 2018.
  12. ^ Chang, Kenneth (5 December 2020). "Japan's Journey to an Asteroid Ends With a Hunt in Australia's Outback". The New York Times. Archived from the original on 20 January 2024. Retrieved 5 December 2020.
  13. ^ a b Rincon, Paul (6 December 2020). "Hayabusa-2: Capsule with asteroid samples in 'perfect' shape". BBC News. Archived from the original on 24 October 2023. Retrieved 6 December 2020.
  14. ^ a b c d Tachibana, S.; Abe, M.; Arakawa, M.; Fujimoto, M.; Iijima, Y.; Ishiguro, M.; Kitazato, K.; Kobayashi, N.; Namiki, N.; Okada, T.; Okazaki, R.; Sawada, H.; Sugita, S.; Takano, Y.; Tanaka, S.; Watanabe, S.; Yoshikawa, M.; Kuninaka, H. (2014). "Hayabusa2: Scientific importance of samples returned from C-type near-Earth asteroid (162173) 1999 JU3". Geochemical Journal. 48 (6): 571–587. Bibcode:2014GeocJ..48..571T. doi:10.2343/geochemj.2.0350.
  15. ^ a b c Yuichi Tsuda; Makoto Yoshikawa; Masanao Abe; Hiroyuki Minamino; Satoru Nakazawa (October–November 2013). "System design of the Hayabusa 2 – Asteroid sample return mission to 1999 JU3". Acta Astronautica. 91: 356–362. Bibcode:2013AcAau..91..356T. doi:10.1016/j.actaastro.2013.06.028.
  16. ^ Zukerman, Wendy (18 August 2010). "Hayabusa 2 will seek the origins of life in space". New Scientist. ISSN 0262-4079. Archived from the original on 24 October 2023.
  17. ^ "JAXA Report on Hayabusa2" (PDF). JAXA. 21 May 2014. Archived (PDF) from the original on 4 March 2016.
  18. ^ Vilas, Faith (25 February 2008). "Spectral characteristics of Hayabusa 2 near-Earth asteroid targets 162173 1999 JU3 AND 2001 QC34". The Astronomical Journal. 135 (4): 1101. Bibcode:2008AJ....135.1101V. doi:10.1088/0004-6256/135/4/1101. target for the planned Japanese mission Hayabusa2
  19. ^ a b c Yoshikawa, Makoto (6 January 2011). 小惑星探査ミッション「はやぶさ2 [Asteroid Exploration Mission "Hayabusa2"] (PDF). 11th Symposium on Space Science (in Japanese). Archived (PDF) from the original on 23 January 2024. Retrieved 20 February 2011.
  20. ^ Clark, Stephen (3 December 2014). "Hayabusa2 launches on audacious asteroid adventure". Spaceflight Now. Archived from the original on 14 October 2023. Retrieved 3 December 2014.
  21. ^ a b Clark, Stephen (29 January 2012). "Japan's next asteroid probe approved for development". Archived from the original on 29 October 2023. Retrieved 29 October 2012.
  22. ^ Keiji Tachikawa (2007). "The President's New Year Interview". jaxa.jp. JAXA. Archived from the original on 5 February 2012. Retrieved 28 April 2007.
  23. ^ Clark, Stephen (11 August 2010). "Asteroid probe, rocket get nod from Japanese panel". Spaceflight Now. Archived from the original on 12 January 2024. Retrieved 29 October 2012.
  24. ^ "Imaging Ryugu from an altitude of 6km". JAXA. 25 July 2018. Archived from the original on 28 October 2023.
  25. ^ "hibou" is not Japanese nor abbreviation; it is the French word for owl and pronounced as such, イブー (i-boo).
  26. ^ Hayabusa-2: Japan's rovers ready for touchdown on asteroid, Paul Rincon, BBC News 20 September 2018
  27. ^ "Japanese Probe Drops Tiny Hopping Robots Toward Big Asteroid Ryugu". Space.com. 21 September 2018.
  28. ^ a b Bartels, Meghaan (22 September 2018). "They Made It! Japan's Two Hopping Rovers Successfully Land on Asteroid Ryugu". Space.com. Archived from the original on 25 October 2023.
  29. ^ MASCOT lands safely on asteroid Ryugu, Press release, DLR Press Portal, 3 October 2018
  30. ^ a b Schedule changes for the touchdown operation, JAXA, University of Tokyo and collaborators, Hayabusa2 Project, 14 October 2018
  31. ^ Otsuka, Minoru (9 January 2019). "はやぶさ2のタッチダウン候補地は2カ所に、どちらが最適?" [Hayabusa2's touchdown candidate sites narrowed down to two, which is the most optimal?]. Mynavi news (in Japanese). Archived from the original on 28 October 2023. Retrieved 9 January 2019.
  32. ^ a b New Photos Show the Surprisingly Big Crater Blasted Into Asteroid Ryugu by Japan's Hayabusa2 Probe, George Dvorsky, Gizmodo, 22 May 2019
  33. ^ a b c [Japan's Hayabusa2 spacecraft grabs epic close-up shot just 30 feet above asteroid], Jackson Ryan, C-net, 5 June 2019
  34. ^ a b c Hasegawa, Kyoko (11 July 2019). "Japan's Hayabusa2 probe makes "perfect" touchdown on asteroid". phys.org.
  35. ^ Hayabusa-2 capsule located in Australian desert
  36. ^ What's the benefit of sample-return?
  37. ^ a b c d e Operation Status of Ion Engines of Asteroid Explorer Hayabusa2, Nishiyama, Kazutaka; Hosoda, Satoshi; Tsukizaki, Ryudo; Kuninaka, Hitoshi; JAXA, January 2017
  38. ^ The Ion Engine System for Hayabusa2 Archived 6 November 2014 at the Wayback Machine, The 32nd International Electric Propulsion Conference, Wiesbaden, Germany, September 11–15, 2011
  39. ^ a b c d e f g h i j k l m n o p q r s t u v w Hayabusa2 Information Fact Sheet JAXA 29 July 2018
  40. ^ Kameda, S.; Suzuki, H.; Takamatsu, T.; Cho, Y.; Yasuda, T.; Yamada, M.; Sawada, H.; Honda, R.; Morota, T.; Honda, C.; Sato, M.; Okumura, Y.; Shibasaki, K.; Ikezawa, S.; Sugita, S. (2017). "Preflight Calibration Test Results for Optical Navigation Camera Telescope (ONC-T) Onboard the Hayabusa2 Spacecraft". Space Science Reviews. 208 (1–4): 17–31. Bibcode:2017SSRv..208...17K. doi:10.1007/s11214-015-0227-y. S2CID 255069232.
  41. ^ "Current status of the asteroid explorer, Hayabusa2, leading up to arrival at asteroid Ryugu in 2018" (PDF). JAXA. 14 June 2018. Archived (PDF) from the original on 28 October 2023. Retrieved 20 June 2018.
  42. ^ Terui, Fuyuto; Tsuda, Yuichi; Ogawa, Naoko; Mimasu, Yuya (July 2014). 小惑星探査機「はやぶさ2」の航法誘導制御における自動・自律機 [Autonomy for Guidance, Navigation and Control of Hayabusa2] (PDF). Artificial Intelligence (in Japanese). 29 (4). JAXA. ISSN 2188-2266. Archived (PDF) from the original on 24 January 2024. Retrieved 9 July 2018.
  43. ^ Yoshikawa, Makoto (16 January 2012). はやぶさ2プロジェクトについて [About the Hayabusa2 Project] (PDF) (in Japanese). Archived (PDF) from the original on 2 November 2023. Retrieved 9 July 2018.
  44. ^ a b Keane, Phillip (21 June 2018). "A detailed look at Japan's Hayabusa2 asteroid exploration mission". SpaceTech Asia. Archived from the original on 1 November 2023.
  45. ^ Okada, Tatsuaki; Fukuhara, Tetsuya; Tanaka, Satoshi; Taguchi, Makoto; Imamura, Takeshi; Arai, Takehiko; Senshu, Hiroki; Ogawa, Yoshiko; Demura, Hirohide; Kitazato, Kohei; Nakamura, Ryosuke; Kouyama, Toru; Sekiguchi, Tomohiko; Hasegawa, Sunao; Matsunaga, Tsuneo (July 2017). "Thermal Infrared Imaging Experiments of C-Type Asteroid 162173 Ryugu on Hayabusa2". Space Science Reviews. 208 (1–4): 255–286. Bibcode:2017SSRv..208..255O. doi:10.1007/s11214-016-0286-8. hdl:1893/26994.
  46. ^ Lakdawalla, Emily (5 October 2018). "MASCOT landing on Ryugu a success". The Planetary Society. Archived from the original on 24 October 2023.
  47. ^ Yoshimitsu, Tetsuo; Kubota, Takashi; Tsuda, Yuichi; Yoshikawa, Makoto (23 September 2018). "MINERVA-II1: Successful image capture, landing on Ryugu and hop!". JAXA Hayabusa2 Project. JAXA. Archived from the original on 29 September 2023. Retrieved 24 September 2018.
  48. ^ "Naming our MINERVA-II1 rovers". JAXA. 13 December 2018. Archived from the original on 15 August 2023.
  49. ^ Ōtsuka, Minoru (28 March 2016). 車輪なしでどうやって移動する?ローバー「ミネルバ2」の仕組み(後編) [How Does It Move Without Wheels? The Mechanism of the Rover 'MINERVA-II' (Part 2)]. MONOist (in Japanese). Archived from the original on 13 December 2023. Retrieved 22 June 2018.
  50. ^ Yoshimitsu, Tetsuo; Kubota, Takashi; Adachi, Tadashi; Kuroda, Yoji (2012). Advanced robotic system of hopping rovers for small solar system bodies (PDF) (Report). S2CID 16105096. Archived (PDF) from the original on 18 April 2021.
  51. ^ "Asteroid explorer, Hayabusa2 press conference" (PDF). JAXA. p. 21.
  52. ^ a b Yoshimitsu, Tetsuo; Kubota, Takashi; Tomiki, Atsushi; Yoshikaw, Kent (24 October 2019). Operation results of MINERVA-II twin rovers onboard Hayabusa2 asteroid explorer (PDF). 70th International Astronautical Congress. International Astronautical Federation. Retrieved 25 January 2020.
  53. ^ Ho, Tra-Mi. "MASCOT – Mobile Asteroid Surface Scout". German Aerospace Center. Archived from the original on 15 November 2012.
  54. ^ "Hayabusa2/MASCOT at a glance – Technical specifications and mission timeline". German Aerospace Center. Archived from the original on 22 June 2018. Retrieved 22 June 2018.
  55. ^ Jaumann, R.; Bibring, J. P.; Glassmeier, K. H.; Grott, M.; Ho, T.-M.; Ulamec, S.; Schmitz, N.; Auster, H.-U.; Herčik, D.; Biele, J.; Krause, C.; Kuninaka, H.; Okada, T.; Yoshikawa, M.; Watanabe, S.; Fujimoto, M.; Pilogret, C.; Hamm, V.; Koncz, A.; Spohn, T. (2017). "A Mobile Asteroid Surface Scout (MASCOT) for the Hayabuse 2 Mision to Ryugu" (PDF). EPSC Abstracts. 11. EPSC2017-548. Archived (PDF) from the original on 24 October 2023.
  56. ^ a b Graham, William (2 December 2014). "Japanese H-IIA kicks off Hayabusa2's asteroid mission". NASASpaceFlight.com. Retrieved 4 December 2014.
  57. ^ Ho, Tra-Mi; et al. (2017). "MASCOT—The Mobile Asteroid Surface Scout Onboard the Hayabusa2 Mission". Space Science Reviews. 208 (1–4): 339–374. Bibcode:2017SSRv..208..339H. doi:10.1007/s11214-016-0251-6. S2CID 255067977.
  58. ^ a b Are Japanese hopping robots safe on asteroid Ryugu? Mike Wall, Space.com, 21 September 2018
  59. ^ a b @MASCOT2018 (4 October 2018). "All done with work! Oh my... can that be right? I explored Ryugu for more than 17 hours. That is more than my team…" (Tweet) – via Twitter.
  60. ^ InSight: A Geophysical Mission to a Terrestrial Planet Interior, Bruce Banerdt, Jet Propulsion Laboratory, NASA, 7 March 2013   This article incorporates text from this source, which is in the public domain.
  61. ^ Grott, M.; Knollenberg, J.; Borgs, B.; Hänschke, F.; Kessler, E.; Helbert, J.; Maturilli, A.; Müller, N. (1 August 2016). "The MASCOT Radiometer MARA for the Hayabusa 2 Mission". Space Science Reviews. 208 (1–4): 413–431. Bibcode:2017SSRv..208..413G. doi:10.1007/s11214-016-0272-1. S2CID 118245538.
  62. ^ Yada, T.; Abe, M.; Okada, T.; et al. (2022). "Preliminary analysis of the Hayabusa2 samples returned from C-type asteroid Ryugu". Nat Astron. 6 (2): 214–220. doi:10.1038/s41550-021-01550-6. S2CID 245366019.
  63. ^ Jaumann, R.; Schmitz, N.; Ho, T.-M.; SchroderÖ, S. E.; Otto, K. A.; Stephan, K.; Elgner, S.; Krohn, K.; Preusker, F.; Kouyam, T. (23 August 2019). "Images from the surface of asteroid Ryugu show rocks similar to carbonaceous chondrite meteorites". Science. 365 (6455): 817–820. Bibcode:2019Sci...365..817J. doi:10.1126/science.aaw8627. PMID 31439797. S2CID 201616571.
  64. ^ "MASCOT confirms what scientists have long suspected". dlr.de. Retrieved 7 March 2020.
  65. ^ "The near-Earth asteroid Ryugu – a fragile cosmic rubble pile". dlr.de. Retrieved 7 March 2020.
  66. ^ Hercik, David; Auster, Hans-Ulrich; Constantinescu, Dragos; Blum, Jürgen; Fornaçon, Karl-Heinz; Fujimoto, Masaki; Gebauer, Kathrin; Grundmann, Jan-Thimo; Güttler, Carsten; Hillenmaier, Olaf; Ho, Tra-Mi (2020). "Magnetic Properties of Asteroid (162173) Ryugu". Journal of Geophysical Research: Planets. 125 (1): e2019JE006035. Bibcode:2020JGRE..12506035H. doi:10.1029/2019JE006035. hdl:1721.1/136097.2. ISSN 2169-9100.
  67. ^ The Downlink: Station Crew Home, Hayabusa2 Deploys Rover, Jason Davis, The Planetary Society, 4 October 2019
  68. ^ @haya2e_jaxa (2 October 2019). "[MINERVA-II2] MINERVA-II2 is confirmed to have separated today (10/3) at 01:38 JST. The separation time was 00:57 J…" (Tweet) – via Twitter.
  69. ^ See the First Photo of Asteroid Ryugu from the Hopping MASCOT Lander!, Tariq Malik, Space.com, 3 October 2018
  70. ^ a b c Hayabusa2 Mission Update, JAXA Press conference on 5 March 2019, Quote/translation:
    • The second touchdown will be done inside or near the artificial crater created by SCI. (Final decision will be made after SCI operation whether or not to actually perform the second try.)
    • There is a high probability that a third touchdown will not be done.
    ※ Reason for choosing to give priority to experiments with collision equipment
    • It was judged that sample was sufficiently collected with the first touchdown.
    • There is a case in which the amount of light received by some of the optical systems of the bottom surface has decreased due to the first touchdown. There is no problem with normal operation, but a careful preliminary investigation is necessary for touchdown operation. Because it takes time to investigate, SCI operation was done first.
  71. ^ a b Bringing back a C-type asteroid sample (in Japanese), Shogo Tachibana, JAXA, 2013
  72. ^ a b Hayabusa-2: Japan spacecraft touches down on asteroid, Paul Rincon, BBC News, 22 February 2019
  73. ^ "Here's an Update on Hayabusa2's Crater-Creating Explosion". The Planetary Society. Retrieved 24 August 2020.
  74. ^ Hayabusa2 Mission Schedule, JAXA, Accessed 4 October 2018
  75. ^ a b c Major onboard instruments – Re-entry Capsule, Accessed: 2 September 2018
  76. ^ Nishiyama, G.; Kawamura, T.; Namiki, N.; Fernando, B.; Leng, K.; Onodera, K.; Sugita, S.; Saiki, T.; Imamura, H.; Takagi, Y.; Yano, H. (2021). "Simulation of Seismic Wave Propagation on Asteroid Ryugu Induced by The Impact Experiment of The Hayabusa2 Mission: Limited Mass Transport by Low Yield Strength of Porous Regolith". Journal of Geophysical Research: Planets. 126 (2): e2020JE006594. Bibcode:2021JGRE..12606594N. doi:10.1029/2020JE006594. ISSN 2169-9100. S2CID 230574308.
  77. ^ Saiki, Takanao; Sawada, Hirotaka; Okamoto, Chisato; Yano, Hajime; Takagi, Yasuhiko; Akahoshi, Yasuhiro; Yoshikawa, Makoto (2013). "Small carry-on impactor of Hayabusa2 mission". Acta Astronautica. 84: 227–236. Bibcode:2013AcAau..84..227S. doi:10.1016/j.actaastro.2012.11.010.
  78. ^ "はやぶさ2、カプセル分離に成功 6日未明に着地へ". The Nikkei (in Japanese). 5 December 2020. Retrieved 5 December 2020.
  79. ^ What's the benefit of sample-return?, Jason Davis, The Planetary Society, 5 July 2018
  80. ^ Extraterrestrial Sample Curation Center
  81. ^ Normile, Dennis (7 December 2020). "Japan's Hayabusa2 capsule lands with carbon-rich asteroid samples". Science | AAAS. Retrieved 9 December 2020.
  82. ^ "Japan's Hayabusa2 spacecraft brings pieces of asteroid back to earth". News Asia Today. 7 December 2020. Retrieved 9 December 2020.
  83. ^ Lauretta, Dante (20 October 2014). "Collaboration between OSIRIS-REx and Hayabusa2". The Planetary Society. Archived from the original on 13 February 2020. Retrieved 12 February 2020.
  84. ^ Sarli, Bruno Victorino; Tsuda, Yuichi (2017). "Hayabusa2 extension plan: Asteroid selection and trajectory design". Acta Astronautica. 138: 225–232. Bibcode:2017AcAau.138..225S. doi:10.1016/j.actaastro.2017.05.016.
  85. ^ 98943 (2001 CC21) – Mid-sized Apollo-class Asteroid, spacereference.org, 2019, Judy Mou and Ian Webster
  86. ^ "はやぶさ2、次のミッションは小惑星「1998KY26」...JAXA". The Yomiuri Shimbun (in Japanese). 13 September 2020. Archived from the original on 5 December 2020. Retrieved 14 September 2020.
  87. ^ "Japan's Hayabusa2 aims to probe asteroid '1998KY26' in 2031". The Mainichi Newspapers. 15 September 2020. Archived from the original on 15 September 2020. Retrieved 15 September 2020.
  88. ^ a b c "Hayabusa 2 Press conference materials – 15 September 2020" (PDF).
  89. ^ Wall, Mike (5 December 2020). "Japanese space capsule carrying pristine asteroid samples lands in Australia". Space.com. Archived from the original on 25 September 2023. Retrieved 11 December 2020.
  90. ^ "小惑星探査機「はやぶさ2」記者説明会" (PDF) (in Japanese). JAXA. 15 September 2020. Retrieved 17 September 2020.
  91. ^ "はやぶさ2、再び小惑星へ 地球帰還後も任務継続―対象天体を選定へ・JAXA" [Hayabusa2 will explore another asteroid, continuing mission after returning target sample to Earth] (in Japanese). Jiji Press. 9 January 2020. Archived from the original on 24 May 2020. Retrieved 9 January 2020.
  92. ^ Bartels, Meghan (12 August 2020). "Japan may extend Hayabusa2 asteroid mission to visit 2nd space rock". Space.com. Retrieved 13 August 2020.
  93. ^ Hirabayashi, Masatoshi; Yoshikawa, Makoto; Mimasu, Yuya; Tanaka, Satoshi; Saiki, Takanao; Nakazawa, Satoru; Tsuda, Yuichi; Tatsumi, Eri; Popescu, Marcel; Pravec, Petr; Urakawa, Seitaro; Yoshida, Fumi; Hirata, Naru; Kamata, Shunichi; Kitazato, Kohei (15 February 2023). Hayabusa2#'s Exploration to Asteroids 2001 CC21 and 1998 KY26 Provides Key Insights Into Planetary Defense. 8th IAA Planetary Defense Conference. Vienna, Austria. Archived from the original on 23 January 2024.
  94. ^ "2022/06/29 What's new". JAXA Hayabusa2 porject (in Japanese). Retrieved 24 September 2023.

External links edit

  • Hayabusa2 project website
  • JAXA Hayabusa2 website
  • Hayabusa2 Science Data Archives hosted by the DARTS archive (ISAS)
  • MASCOT related publications by the Institute of Planetary Research hosted by Europlanet
  • Hayabusa2 images scientific commentary Archived 28 October 2020 at the Wayback Machine, University of Tokyo
  • Asteroid Explorer Hayabusa2, NEC
  • Hayabusa2 3D model, Asahi Shinbun