Tag Archives: Hayabusa 2

Hayabusa-2 aborts close-in drop of visual marker on Ryugu

Japan’s asteroid probe Hayabusa-2 automatically aborted a planned drop of a visual markee on the asteroid Ryugu at the site where the probe created a crater in April.

Thursday’s mission was to observe the targeted area in detail and drop a marker from an altitude of 10 meters. But officials say the probe automatically suspended the operation after it descended to about 50 meters above the surface. It then headed toward its standby position of 20 kilometers above Ryugu. Hayabusa2 is designed to automatically abort its landing if it detected any irregularity. The agency is looking into the cause of the arrested descent.

Once the marker is eventually in place, they will use it for guidance during a a second touchdown to grab further samples, this time hopefully of material churned up by the explosion that created the crater.

Share

Ten secondary craters produced on Ryugu by Hayabusa-2’s manmade impact

The Hayabusa-2 science team has announced that it has found ten additional secondary craters produced from ejecta from the manmade impact the spacecraft created on Ryugu on April 5.

The secondary craters appear to be about a yard across each, while the initial crater is about thirty feet wide with a depth of six to ten feet.

Share

The new man-made crater on Ryugu

Man-made crater on Ryugu

The Hayabusa-2 science team has released before and after images of the spot on Ryugu where the spacecraft’s explosive projectile caused the creation of a small crater.

On the left above is the before, with the new crater indicated by the circle on the right. Note the rocks in both pictures, some now partly covered with debris. They did not give a scale, but this is a very small area, probably less than a few feet across.

They now need to analyze whether they can safely touchdown at this spot and grab a sample.

Share

Hayabusa-2 confirms man-made crater on Ryugu

In a planned fly-over of Ryugu yesterday Hayabusa-2 took its first direct images of the location where it had fired an explosive projectile and thus confirmed the creation of a man-made crater by that projectile.

“The asteroid’s terrain has clearly been altered,” said Yuichi Tsuda, an associate professor at the Japan Aerospace Exploration Agency.

Hayabusa2, which began its descent toward the asteroid Wednesday afternoon, captured images of its surface to determine the existence of the crater after it successfully shot a metal projectile at Ryugu on April 5 in an experiment deemed the first of its kind.

According to the JAXA, the probe photographed the area hit by the projectile from a distance of 1.7 km. The agency compared images of the asteroid’s surface before and after the shooting of the projectile to determine the presence of a man-made crater.

They have not yet released any of these images. They will use them however for planning a touchdown and sample grab within this crater in next few months.

Share

Hayabusa-2 has begun close fly-in of man-made crater

Hayabusa-2 has begun its fly-in of Ryugu to make its first close observation of the man-made crater it created on the asteroid’s surface on April 4.

The link takes you to the images downloaded in real time from the spacecraft’s navigation camera. New images appear approximately every thirty minutes. The approach has only just begun, so Ryugu remains somewhat small in the images. This will change as the day proceeds.

Share

April 25 set for Hayabusa-2’s first observations of artificial crater

The Hayabusa-2’s science team has scheduled their first observations of the artificial crater the spacecraft made on the surface of the asteroid Ryugu for April 25.

The probe will observe the crater, which was generated during an impact experiment on April 5, from a height of 1.7 kilometers. JAXA will collate the data with photographs of the surface taken near the impact point to measure the size and location of the crater. It will also examine the dispersion of rocks and judge whether Hayabusa2 can land to take samples.

This is only their first assessment. Once they feel comfortable about getting closer, they will then plan the spacecraft’s second touchdown and sample collection, this time hopefully from within that crater.

Share

Hayabusa-2’s successfully bombs Ryugu

impact on Ryugu

Japan’s Hayabusa-2 probe yesterday successfully impacted an explosive charge on the surface of the asteroid Ryugu, creating a crater for observing the interior geology.

The image to the right was taken by a camera that has separated from Hayabusa-2 and stayed closer to the impact. It shows material flying off the asteroid’s surface, at the horizon line.

Hayabusa-2 — which moved to the other side of the asteroid to stay clear of any ejecta — will next arc around and get close to this impact site to study it. They first need to make sure the ejecta has cleared.

Share

Hayabusa-2 to take close look at planned explosive impact point on Ryugu

Flight plan for Hayabusa-2's rehearsal

Beginning today Hayabusa-2 will do a two-day close approach of Ryugu in order to get good baseline images of the point on the surface where they will fire an explosive projectile in the first week in April. As they note:

Currently, we have scheduled the small carry-on impactor operation (SCI operation) for the first week in April. The purpose of the SCI operation is to create a crater on the surface of Ryugu, and it is important to be able to compare the asteroid surface before and after the SCI operation.

The graph on the right shows the flight plan. I expect they will do the same for this maneuver as they have done with previous close approaches, and provide real-time images as they happen.

Share

Confirmed: Ryugu is a rubble pile

Close-up of Ryugu's surface
Click for source paper [pdf].

At a special session today dedicated to results from the Hayabusa-2 probe to the asteroid Ryugu at the 50th Lunar and Planetary Science Conference in Texas, scientists confirmed from numerous data and images that the asteroid has a low density, is covered with boulders and pebbles, is very porous, and is thus a rubble pile that is held together by gravity, barely.

From their lead presentation [pdf]:

The estimated total porosity is even higher than that of rubble-pile asteroid Itokawa (44 ± 4%), indicating that asteroid Ryugu is also a rubble pile. This is consistent with a theory arguing that all Solar System bodies with diameter of ~1 km should be rubble piles and might have formed from reaccumulation of fragments generated by catastrophic disruption events of ~100-km sized parent bodies.

They also posit that the asteroid’s diamond shape is caused by the asteroid’s 3.5 hour rotation, which causes its weak rubble pile structure to be easily pulled to the equator, and then outward.

Another paper [pdf] did crater counts, and found that there are fewer large craters than one would expect.

The density of large craters (D>100 m) on Ryugu is lower than the empirical saturation level and its slope is steeper than that of the saturated distribution, suggesting that craters larger than 100 m are not saturated and the size distribution reflects the crater production function. However, craters smaller than 100 m are significantly under-saturated, suggesting that some crater erasure processes such as seismic shaking and armoring effect are active on the Ryugu surface. Based on cratering chronology model for the main belt, the surface age of Ryugu is estimated to be 5–200 [million years] from the size–frequency distribution of craters larger than 100 m.

In other words, this rubble pile is constantly being shaken by its rotation and time and later impacts, which steadily rewrites the surface.

If this asteroid was headed to Earth, I imagine the only safe solution to prevent disaster would be to slowly and gently deflect it so it only flies past. To do this will require an arrival far in advance of the schedule impact, to give time for the deflection process to work.

Share

Hayabusa-2 schedules explosion on Ryugu

The Hayabusa-2 science team has scheduled April 5 for when it will use the spacecraft to fire an explosive device into Ryugu to create a crater and debris cloud.

The probe is scheduled to detach a device loaded with explosives some 500 meters away from Ryugu. The device will set off the explosives using a timer some 40 minutes later and launch a copper “impactor” weighing about 2 kilograms into the asteroid’s surface.

The target point is several hundreds of meters away from where the space probe first touched down. The mission will require the spacecraft to move quickly to the other side of the asteroid so it won’t get hit by flying shards from the blast. A detached camera will shoot the moment of impact.

JAXA will analyze the size and shape of the crater, and how rocks fly off in a bid to collect underground samples for possible clues to the origin of the solar system.

This is different than the touchdown last month, as the spacecraft itself will not get close to the asteroid.

Share

Hayabusa-2 to get close to Ryugu again to observe next touchdown point

Hayabusa-2’s engineering team has decided it will on March 8 do a close approach to within 75 feet of its next planned touchdown target site in order to inspect it.

The DO-S01 operation schedule is shown in Figure 2. The spacecraft will begin descending on March 7 at 13:27 (JST, onboard time: times below are stated similarly) at a speed of 0.4m/s. The speed will then be reduced to 0.1 m/s around 23:47 on the same day. Continuing descent at this rate, we will reach our lowest altitude at around 12:22 on March 8 and then immediately begin to rise. The altitude of this lowest point will be about 23m. Please note that the times stated here are the planned values but the actual operation times may differ.

As before, they will upload navigation images as this approach is happening.

Share

Video from Hayabusa-2’s touchdown

The Hayabusa-2 science team has released a video taken of the spacecraft’s quick touchdown and sample grab on the asteroid Ryugu.

I have embedded the video below the fold. It not only shows the incredible rockiness of Ryugu’s surface, with the spacecraft barely missing a large rock as it came down, it also clearly shows the resulting debris cloud and surface changes after touchdown and the firing of Hayabusa-2’s projectile into the surface to throw up material that the spacecdraft could catch. You can actually see pebbles flying about below and around the spacecraft as it quickly retreats.

The Hayabusa-2 science team plans another touchdown in the next few months, this time using a different technique to disturb the surface and grab the resulting ejecta.
» Read more

Share

Hayabusa-2 touchdown images released

Surface of Ryugu 1 minute after touchdown

The Hayabusa-2 science team today released images taken during its quick touchdown on the asteroid Ryugu last week.

The image to the right was taken:

roughly 1 minute after touchdown at an estimated altitude of about 25m (error is a few meter) [80 feet]. The color of the region beneath the spacecraft’s shadow differs from the surroundings and has been discolored by the touchdown. At the moment, the reason for the discoloration is unknown but it may be due to the grit that was blown upwards by the spacecraft thrusters or bullet (projectile).

The image proves that everything on Hayabusa-2 worked as planned, and it almost certainly captured some of that grit.

They are going to do at least two more touchdowns before they have Hayabusa-2 leave Ryugu and head back to Earth.

Share

Confirmed: Hayabusa-2 grabbed got a sample of Ryugu

The Hayabusa-2 science team has confirmed that in the spacecraft’s quick touchdown on the surface of the asteroid Ryugu today it successfully snagged an asteroid sample.

Mission team members announced at about 6:30 p.m. EST (2330 GMT) today that the order to fire the bullet had been issued, and that Hayabusa2 had moved away from Ryugu as planned. But it took a few more hours for them to confirm that the bullet had indeed fired, and that sample collection occurred.

…The collected samples are key to this objective: The Ryugu material will come down to Earth in a special return capsule in December 2020. Scientists in labs around the world can then scrutinize the stuff with far more advanced equipment than the Hayabusa2 team could pack onto a single spacecraft.

The sample bounty will include more than just the material Hayabusa2 collected today. The mothership is expected to grab two more samples in the coming weeks and months. The second sampling sortie will unfold much like today’s did, but the third will be dramatically different: Hayabusa2 will fire a copper projectile into Ryugu, wait a bit for the dust to clear, and then swoop in to grab material from the newly created crater. This formerly subsurface stuff will be pristine, unaffected by weathering from deep-space radiation.

More thrills to come, obviously.

Share

Hayabusa-2 has begun approach to Ryugu

Ryugu during approach

Hayabusa-2 has begun its approach to Ryugu, aiming for a quick touchdown and sample grab at approximately 7:06 pm (Eastern) tonight. The image at the right is the most recent taken during the approach.

The risks? From the Hayabusa-2 website:

Our original schedule planned for touchdown in late October of last year (2018). However, Ryugu was revealed as a boulder strewn landscape that extended across the entire surface, with no flat or wide-open regions. Before arriving at Ryugu, it was assumed there would be flat areas around 100 meters in size. But far than finding this, we have not even seen flat planes 30 meters across!

During the scheduled time for touchdown in late October, we did not touchdown but descended and dropped a target marker near the intended landing site. We were able to drop the target marker in almost the planned spot and afterwards we examined the vicinity of the target marker landing site in detail. Finally, the area denoted L08-E1 was selected as the place for touchdown.

From the first link above you can see approach images as they are downloaded today, about once every half hour.

Share

Hayabusa-2 prepares to land

Ryugu's northen hemisphere

The JAXA science team has released a set of images taken in January by Hayabusa-2 of its landing site on Ryugu, describing how those images helped map the region where touchdown will occur on February 22. The image on the right is one such image.

[It] shows a diagonally imaged photograph of Ryugu, captured by moving the spacecraft towards the direction of the north pole. The upper side of the image shows the north pole and reveals a landscape dominated with many large boulders. The white band extending to the left and right slightly below the center of the image is the equatorial ridge (Ryujin Ridge). The arrow tip marks the planned touchdown site and you can see this site is on the main ridge.

This is the first time we have images the northern hemisphere of Ryugu. In this observation, we acquired data on the equatorial region of Ryugu, the southern and northern hemisphere. Imaging the entire area is very important for creating accurate global shape models for Ryugu.

They should begin beaming images down of the landing approach sometime tomorrow, and will do so about every 30 minutes throughout the sequence.

Share

Hayabusa-2 to attempt asteroid landing on February 22

JAXA, Japan’s space agency, today announced that Hayabusa-2 will attempt a landing on the asteroid Ryugu on February 22.

The landing was delayed from October because of the unexpected roughness of Ryugu’s surface, which literally has no spot smooth enough and large enough for Hayabusa-2, as planned. This landing will therefore be attempted in one of two places that are almost large enough, but not quite. It thus carries some additional risks.

Share

Hayabusa-2 names features on Ryugu

The Hayabusa-2 science/engineering teams have now revealed the names they have given to all the significant features on Ryugu that they have photographed.

To name a place on a celestial body in the Solar System, you must first decide on a theme. For example, the theme for places on Venus is the “names of goddesses”. During discussions between the domestic and overseas project members, suggestions such as “names of castles around the world”, “word for ‘dragon’ in different languages” and the “names of deep-sea creatures” were proposed for the place name theme on Ryugu. After an intense debate, the theme was selected to be “names that appear in stories for children” and a theme proposal was put to the IAU WG. The proposal was accepted on September 25, after which the discussion moved to selecting the topographical features to be named and the choice of name.

The link provides a table describing the meaning of many of the names, which is often quite amusing. For example, Kolobok Crater comes from a Russian story about “A small round bread that ran away from home.”

Share

Hayabusa-2 to grab asteroid samples in February

The Hayabusa-2 science team has decided that it will make their first attempt to land and grab samples from the asteroid Ryugu in February.

“The time has finally come,” JAXA senior project member Takashi Kubota said at a news conference on Jan. 8. “Two candidate landing spots have their own advantages and drawbacks, but we will robustly try to collect samples.” The two sites are near the equator of the asteroid. JAXA said it will pick one by early February.

Between Feb. 18 and Feb. 23, the Hayabusa 2 will start descending from its “home position” at an altitude of 20 kilometers from the asteroid. JAXA will use “target markers,” which will be dropped on Ryugu beforehand, to guide the probe.

Hayabusa 2 is scheduled to make three touch-and-go landings.

There are clearly risks here, since the asteroid is strewn so completely with rocks and boulders.

Share

Comparing Ryugu and Bennu

Link here. As much as they are alike, which is not surprising as they both come from the same asteroid family, the article notes the surprising differences.



Both asteroids are also liberally strewn with boulders – a challenge to mission planners on each team, who hope to descend close enough to scoop up samples for return to Earth. “It’s certainly more rugged than we had expected,” Lauretta says. 

But while boulders on Ryugu look to be unpleasantly ubiquitous, Bennu’s terrain is more varied, with more-obvious places where a safe touchdown might be possible. And, Lauretta notes, the OSIRIS-REx spacecraft is only recently arrived.

“We have a long time to explore and make the crucial decisions about where to go,” he says.

The biggest difference has to do with water. Even though scientists believe them to be portions of the same parent body, which broke apart between 800 million and one billion years ago, Bennu appears to be water rich, while Ryugu is less so. Within a week of arrival, infrared spectrometers on OSIRIS-REx were finding evidence of water-bearing minerals, and not just in localised patches. “We saw this in every single one of the spectra we have taken to date,” says Amy Simon, of NASA’s Goddard Space Flight Centre in Greenbelt, Maryland. 

One of the reasons Bennu was chosen as OSIRIS-REx’s target, Lauretta says, was the hope it would be rich in water, and possibly in organic compounds.

The similarities and differences in the samples both spacecraft will bring back will be most revealing.

Share

Oblique view of Hayabusa-2’s most recent landing rehearsal

Cool movie time! The Hayabusa-2 science team has released a small movie of images taken by a side-mounted camera of the spacecraft’s most recent landing rehearsal, showing the spacecraft ascend from its closest approach from an oblique angle.

I have embedded the movie from these images below the fold. As they note,

Images taken with the small monitor camera (CAM-H) during the Touchdown 1 Rehearsal 3 operation (TD1-R3). One image was captured every second from immediately after the spacecraft began to ascend (altitude 21m) on October 25, 2018 at 11:47 JST. The spacecraft was rising at about 52cm/s.

It appears the closest image was taken from about 21 meters away, about 65 feet, and gives a sense of scale. It also reveals once again how difficult that landing in January is going to be. Though this location is thought to be the smoothest spot on Ryugu, it is still littered with rocks that could cause problems.
» Read more

Share

Hayabusa-2’s highest resolution image so far

Ryugu up close

The Hayabusa-2 science team has released the highest resolution image taken by the spacecraft so far. The image on the right, reduced to post here, is that image. Click on it to see the full resolution version.

The image resolution is about 4.6mm/pixel. This is the highest resolution image that Hayabusa2 has taken so far and even small rocks with a diameter of 2 – 3cm are clearly visible. The maximum resolution of AMICA –the camera at the time of the first Hayabusa mission— was 6 mm/pixel, so even its resolution has now been exceeded. As the image captured of the asteroid surface from the spacecraft, it will be one of the highest resolution to be taken of Ryugu (MINERVA-II1 and MASCOT which landed on the surface, have captured even higher resolution images).

A feature from the image is the lack of regolith (sandy substance). This was suspected to be true from the images obtained so far, but it is more clearly seen in this high resolution photograph. There is also a collection of pebbles with different colors, which may be evidence that the surface material of Ryugu is mixed.

This was taken during the second landing rehearsal about two weeks ago. The image clearly shows the rubble pile that is Ryugu, lacking anything but cemented rocks. It also illustrates the landing problem faced by Hayabusa-2’s engineers. They need a flat smooth area to land, and they have not really found one that fits their needs.

Share

Hayabusa-2 completes third Ryugu touchdown rehearsal

Ryugu up close

Hayabusa-2 today completed its third Ryugu touchdown rehearsal.

According to their operation schedule, they were planning to descent to about 20 meters of the surface, about 65 feet. The image on the right is the closest image taken during the rehearsal. You can see the shadow of Hayabusa-2 in the middle of the frame.

They have not released any information about the rehearsal results. The key here is how accurately they were able to get Hayabusa-2 to approach the asteroid’s largest flat spot, a tiny 20 meter wide spot less than half the size of their original planned landing diameter. From the image, it is unclear how successful they were.

They will now spend the next two months analyzing the data from their landing rehearsals in preparation for a landing attempt in January. During this time observations will be reduced because the Sun will be between the Earth and the asteroid.

Share

Hayabusa-2 will do two touchdown rehearsals prior to landing in January

In order to test whether they can bring Hayabusa-2 down to the surface within a circle only 20 meters (65 feet) across (the largest smooth landing area they have found so far on Ryugu), their engineering team has decided to first do two more touchdown rehearsals in October.

In the area where the spacecraft will touchdown, it is dangerous to have boulders with a height greater than about 50cm. Since the length of the sampler horn is about 1m and the spacecraft will be to be slightly inclined during the touchdown, there is a possibility that if a boulder with a height above about 50cm is present, it will strike the main body of the spacecraft or the solar panels. Viewed from the position in Figure 2, there is no boulder larger than 50cm in the area L08-B. L08-B is the widest part within all the candidate sites without a boulder larger than 50cm.

The difficulty is that area L08-B is only about 20m in diameter. Originally, it was assumed that a safe region for touchdown would be a flat area with a radius of about 50m (100m in diameter). This has now become a radius of just 10m; a fairly severe constraint. On the other hand, during the descent to an altitude of about 50m during the MINERVA-II1 and MASCOT separation operations, we were able to confirm that the spacecraft can be guided within a position accuracy of about 10m for a height 50m above the surface of Ryugu (Figure 3). This is a promising feature for touchdown.

Although the spacecraft can be controlled with a position error of 10m at an altitude down to 50m, there remains the question of whether this accuracy can be retained as the spacecraft descends to the surface. This must be confirmed before touchdown operations. Therefore, the touchdown itself will be postponed until next year, during which time we will have two touchdown rehearsals; TD1-R1-A and TD1-R3.

After the rehearsals in October they must wait until January to do the landing because in November and December the sun will be in-between the Earth and the spacecraft, making operations more difficult. They want to also use this time to review the results of the rehearsals to better prepare for the January landing.

Share

MASCOT’s journey on Ryugu

MASCOT's journey on Ryugu

MASCOT’s German science team has released a summary of the lander/hopper’s results and seventeen hour journey across the surface of the asteroid Ryugu. The image on the right, reduced and cropped to post here, shows the spacecraft approach, landing, and numerous hops across the surface. If you click on the image you can see the full high resolution image.

Having reconstructed the events that took place on asteroid Ryugu, the scientists are now busy analysing the first results from the acquired data and images. “What we saw from a distance already gave us an idea of what it might look like on the surface,” reports Ralf Jaumann from the DLR Institute of Planetary Research and scientific director of the MASCOT mission. “In fact, it is even crazier on the surface than expected. Everything is covered in rough blocks and strewn with boulders. How compact these blocks are and what they are composed of, we still do not know. But what was most surprising was that large accumulations of fine material are nowhere to be found – and we did not expect that. We have to investigate this in the next few weeks, because the cosmic weathering would actually have had to produce fine material,” continues Jaumann.

The spacecraft apparently bounced eight times after first contact, then executed three hops. The rubble pile nature that is observed I think explains why the Hayabusa-2 science team decided to delay its own landing for a few months so they could figure out a plan. It really appears that Ryugu does not have any smooth flat spots, as expect.

Share

Hayabusa-2 landing on Ryugu delayed until January

Because of the roughness of the surface of Ryugu, the Hayabusa-2 science team has decided to delay the landing of the spacecraft on the asteroid from the end of this month until late January at the earliest.

JAXA project manager Yuichi Tsuda said they needed more time to prepare the landing as the latest data showed the asteroid surface was more rugged than expected.

“The mission … is to land without hitting rocks,” Tsuda said, adding this was a “most difficult” operation. “We had expected the surface would be smooth … but it seems there’s no flat area.”

.

This decision is a wise one. They will have the ability to land very precisely, and this will give them time to find the least risky spot. It does indicate however that the landing itself is going to be risky, which is probably why they want more time to gather data beforehand. Should the landing fail, the mission will essentially be over. This way they can maximize what they learn.

Share

Images of Mascot by Hayabusa released

MASCOT descending towards Ryugu

The Hayabusa-2 science team today released images taken of MASCOT as it descended to the surface of Ryugu, including images showing where it landed.

In the image on the right, reduced slightly to post here, you can see MASCOT as it slowly moves downward towards the asteroid shortly after its release from Hayabusa-2. At the link there is another image showing the mini-lander as a white dot when it was still about 115 feet above the surface. Other images show its location on the surface where it operated for seventeen hours and completed three hops.

The next big event from Hayabusa-2 will be the spacecraft’s own landing, sometime later this month.

Share
1 2 3