{"id":13616,"date":"2018-09-07T01:07:00","date_gmt":"2018-09-06T17:07:00","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/hayabusa-2-team-sets-dates-for-asteroid-landings\/"},"modified":"2018-09-07T01:07:00","modified_gmt":"2018-09-06T17:07:00","slug":"hayabusa-2-team-sets-dates-for-asteroid-landings","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/hayabusa-2-team-sets-dates-for-asteroid-landings\/","title":{"rendered":"Hayabusa 2 team sets dates for asteroid landings"},"content":{"rendered":"
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Hayabusa 2\u2019s optical navigation camera captured this view of asteroid Ryugu from a distance of 6 kilometers (4 miles) on July 20. Credit: JAXA<\/figcaption><\/figure>\n

Japan\u2019s Hayabusa 2 spacecraft is preparing to release three hopping robots to land on asteroid Ryugu in the coming month, with tiny instruments scientists hope will explore the airless world\u2019s boulder-strewn landscape and return the first images from the surface of an asteroid.<\/p>\n

Two of the landers developed by the Japanese space agency will be deployed together by Hayabusa 2 on Sept. 21, and another landing probe provided by German and French scientists is set for its descent to Ryugu on Oct. 3.<\/p>\n

Those landing attempts will be preceded by a landing rehearsal using the Hayabusa 2 spacecraft to approach within 100 feet (30 meters) of Ryugu next week. The spacecraft is scheduled to reach its closest point to the asteroid Sept. 12, low enough to fire and test its laser range finder, a navigation sensor to be used on future touch-and-go maneuvers to snag a sample of Ryugu for return to Earth.<\/p>\n

Next week\u2019s practice descent will set the stage for a second rehearsal in mid-October, followed by the full sampling run at the end of next month.<\/p>\n

The close-up maneuvers around Ryugu come after more than two months of mapping surveys, revealing Ryugu\u2019s appearance for the first time after Hayabusa 2\u2019s arrival in late June.<\/p>\n

The mission\u2019s early reconnaissance of Ryugu allowed scientists to measure its size and mass. The asteroid has a slightly flattened shape, spanning around 3,280 feet (1 kilometer) in diameter along its equator and approximately 2,880 feet (880 meters) from pole-to-pole.<\/p>\n

Ryugu makes one rotation every 7.63 hours and has a mass of roughly 450 million metric tons (496 million tons), yielding a calculation of the asteroid\u2019s gravity.<\/p>\n

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Scientists developed this shape model of asteroid Ryugu using data from Hayabusa 2\u2019s laser altimeter instrument. Credit: JAXA<\/figcaption><\/figure>\n

Scientists say Ryugu is a C-type asteroid, suggesting it contains primitive building blocks left over the formation of the solar system 4.5 billion years ago. Managed by the Japan Aerospace Exploration Agency, Hayabusa 2 will bring back specimens of the asteroid\u2019s primordial surface for analysis in sophisticated laboratories on Earth.<\/p>\n

Hayabusa 2\u2019s deployable asteroid landers will make a leisurely descent to Ryugu after separation from the Hayabusa 2 mothership at an altitude of around 200 feet (60 meters). Ryugu\u2019s tenuous gravity \u2014 80,000 times weaker than Earth\u2019s gravity field \u2014 will gently tug on the landing probes as they make an uncontrolled free fall to the asteroid, reaching the surface at a speed of less than 1 mph (about 30 centimeters per second).<\/p>\n

The first pair of landers to be released Sept. 21 by Hayabusa 2 are carried inside the same container. The MINERVA-II robots, which each weigh a little more than 2.4 pounds (1.1 kilograms), are designed to hop across Ryugu, using cameras, thermometers and other sensors to investigate Ryugu from the surface.<\/p>\n

Developed by JAXA, the disk-shaped MINERVA-II landers each have a diameter of 6.7 inches (17 centimeters) \u2014 less than the width of a typical dinner plate \u2014 and stand around 2.7 inches (7 centimeters) tall. The Hayabusa 2 mothership will put the landers on a trajectory to touch down in Ryugu\u2019s northern hemisphere.<\/p>\n

A third MINERVA-II lander carried by Hayabusa 2 is set to be released for a landing on Ryugu next year.<\/p>\n

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Artist\u2019s illustration of the MINERVA-II robots carried by Hayabusa 2. The two probes depicted on the left side of the image will be released Sept. 21. Credit: JAXA<\/figcaption><\/figure>\n

The mission\u2019s largest landing craft is MASCOT \u2014 the Mobile Asteroid Surface Scout \u2014 a joint project by the German and French space agencies. It\u2019s due to be released by Hayabusa 2 on Oct. 3.<\/p>\n

Conceived and designed by the same team that developed the Philae lander, which made the first soft landing on a comet in 2014, the MASCOT spacecraft will bounce to a rest on Ryugu somewhere in the asteroid\u2019s southern mid-latitudes.<\/p>\n

\u201cIt\u2019s a very small lander,\u201d said Tra-Mi Ho, MASCOT\u2019s project manager at DLR, the German space agency. \u201cIt\u2019s not bigger than a shoebox, and its weight is not more than 10 kilograms (22 pounds).\u201d<\/p>\n

The MASCOT lander \u201ccarries four scientific instruments,\u201d Ho said. \u201cThere is a wide-angle camera called MASCAM. It is there to determine the geology \u2014 the means to investigate the surface features of Ryugu \u2014 and for that it will require imaging at multiple wavelengths.<\/p>\n

\u201cWe have got a microscope,\u201d Ho said in an Aug. 23 press briefing in Japan. \u201cIt\u2019s a spectral microscope provided by CNES (the French space agency). It is determining the mineralogy. It determines also the content of organic materials and hydrated minerals on the surface \u2014 of the water \u2014 by investigating the spectral features.<\/p>\n

\u201cWe have a got a thermal radiometer,\u201d Ho continued. \u201cIt is called MARA. MARA is detecting or investigating the surface temperature of the asteroid. We have got a magnetometer as well, which is called MASMAG. It is there to determine if a magnetic filed exists in the asteroid or in the boulders.\u201d<\/p>\n

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A technician installs the MASCOT lander into the Hayabusa 2 spacecraft before launching to an asteroid. Credit: DLR<\/figcaption><\/figure>\n

Billed by European scientists as Philae\u2019s \u201clittle brother,\u201d MASCOT carries a self-righting mechanism to orient itself after settling down on Ryugu\u2019s surface. The autonomous lander will also try to hop to different positions on the asteroid during its planned 16-hour mission, which is limited by the capacity of the probe\u2019s battery.<\/p>\n

Ground teams carefully analyzed imagery and science data from Hayabusa 2 to select candidate landing sites for the MINERVA-II and MASCOT spacecraft.<\/p>\n

Scientists wanted to ensure none of the landers end up near Hayabusa 2\u2019s sampling target, located near Ryugu\u2019s equator, and assessed numerous candidate landing sites to find locations relatively free of large boulders. Managers also considered temperature and communications constraints \u2014 all the landers have thermal limits and must relay data back to Earth through Hayabusa 2.<\/p>\n

MASCOT science team members ranked their candidate landing sites during an Aug. 14 meeting in Toulouse, France, and briefed their proposal to Hayabusa 2 officials in Japan the following week. The teams announced the landing site selections for the MINERVA-II and MASCOT robots, along with the first of up to three sampling sites for Hayabusa 2, during a press conference Aug. 23.<\/p>\n

But despite the diligence by engineers and scientists on Earth, the miniature landers must function in an extreme environment, with temperature swings and an asteroid surface marked with numerous boulders that could pose danger for the tiny robots.<\/p>\n

\u201cRyugu seems to be very homogeneous, so you have got more or less the same composition everywhere,\u201d Ho said. \u201cAlthough we are happy, I think I will have sleepless nights until October,\u201d she said. \u201cUntil we land there, we still don\u2019t know how it looks exactly at the landing site \u2026 So the unknown boulder size distribution at the site, which is critical for MASCOT, is still imposing a risk for our mission.\u201d<\/p>\n

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Members of the MASCOT, Hayabusa 2 and MINERVA-II teams (left to right) point out their landing sites. Credit: JAXA<\/figcaption><\/figure>\n

MASCOT was powered on for testing after Hayabusa 2\u2019s arrival at Ryugu, confirming the robot survived its interplanetary cruise inside a carrier bay aboard the Japanese spacecraft. Hayabusa 2 launched on Dec. 3, 2014, and completed its nearly 2 billion-mile (3.2 billion-kilometer) journey to the asteroid June 27.<\/p>\n

\u201cMASCOT has been designed to be robust for launch, and on the asteroid, especially for landing,\u201d Ho said. \u201cIf you consider the MASCOT landing, it\u2019s like you drop MASCOT at roughly (a couple of inches) onto a table. So we think, from an impact point of view, it should be robust.<\/p>\n

\u201cHowever, we do not know how the asteroid looks,\u201d Ho said. \u201cSo, for example, a very unfortunate (scenario) is MASCOT finally settles between two rocks, and it might be trapped.\u201d<\/p>\n

Hayabusa 2\u2019s nano-landers will not be the first spacecraft to achieve a soft landing on an asteroid. That distinction goes to NASA\u2019s NEAR-Shoemaker mission, which made a controlled touchdown on asteroid Eros in 2001 and unexpectedly continued beaming science data back to Earth.<\/p>\n

But NEAR-Shoemaker did not return any asteroid images from the surface of Eros, leaving that \u201cfirst\u201d in space exploration up for grabs by MINERVA-II and MASCOT.<\/p>\n

The Japanese-built MINERVA-II landers are based on a similar craft that flew with Japan\u2019s Hayabusa mission to asteroid Itokawa, but that landing attempt was unsuccessful.<\/p>\n

Hayabusa 2 is one of two sample return missions that are beginning their asteroid exploration campaigns this year. NASA\u2019s OSIRIS-REx mission is scheduled to arrive at asteroid Bennu on Dec. 3, culminating in its own touch-and-go sample grab in mid-2020.<\/p>\n

Hayabusa 2 is set to depart the asteroid in late 2019, with return to Earth scheduled for December 2020 with a parachute-assisted landing of the mission\u2019s sample carrier in Australia.<\/p>\n

Email the author.<\/i><\/b><\/p>\n

Follow Stephen Clark on Twitter: @StephenClark1.<\/strong><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Hayabusa 2\u2019s optical navigation camera captured this view of asteroid Ryugu from a distance of 6 kilometers (4 miles) on July 20. Credit: JAXA Japan\u2019s Hayabusa 2 spacecraft is preparing to release three hopping robots to land on asteroid Ryugu in the coming month, with tiny instruments scientists hope will explore the airless world\u2019s boulder-strewn […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[2882,1519,690,1914,242,455,1965,377],"class_list":["post-13616","post","type-post","status-publish","format-standard","hentry","category-news","tag-asteroid-1999-ju3","tag-asteroids","tag-cnes","tag-dlr","tag-france","tag-germany","tag-hayabusa-2","tag-japan"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/13616"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=13616"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/13616\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=13616"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=13616"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=13616"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}