Honda developing reusable rocket

Capitalism in space: As part of a larger plan to diversify its product line, Japanese car manufacturer Honda announced on September 30th that it is developing a reusable rocket comparable to Rocket Lab’s Electron.

Honda’s press release can be found here. In it the company also proposes to develop technologies for use by colonies on the lunar surface.

All of these proposals so far appear to be nothing more than PowerPoint presentations, but according to the first link above, the company says it will spend about $9 billion per year for the next five years on all these projects, which also include developing a robot and an electric plane that takes off and lands vertically. (The dollar amount seems much too high, but it is based on a conversion from the announced $5 trillion yen total Honda says it is going to spend in next five years for this research and development.)

According to the announcement, the rocket won’t launch until 2030, which will get it into the game very late. It better be revolutionary or it won’t garner much business by then.

BepiColombo about to make first of six Mercury flybys

The European/Japanese BepiColombo probe will make its first of six fly-bys of Mercury on October 1, 2021, as it steadily adjusts its flight path to enter orbit around the planet in 2025.

The mission is made up of two Mercury orbiters, Europe’s Mercury Planetary Orbiter and Japan’s Mio orbiter.

During the flybys it is not possible to take high-resolution imagery with the main science camera because it is shielded by the transfer module while the spacecraft is in cruise configuration. However, two of BepiColombo’s three monitoring cameras (MCAMs) will be taking photos from about five minutes after the time of close approach and up to four hours later. Because BepiColombo is arriving on the planet’s nightside, conditions are not ideal to take images directly at the closest approach, thus the closest image will be captured from a distance of about 1000 km.

The first image to be downlinked will be from about 30 minutes after closest approach, and is expected to be available for public release at around 08:00 CEST on Saturday morning. The close approach and subsequent images will be downlinked one by one during Saturday morning.

The cameras provide black-and-white snapshots in 1024 x 1024 pixel resolution, and are positioned on the Mercury Transfer Module such that they also capture the spacecraft’s solar arrays and antennas. As the spacecraft changes its orientation during the flyby, Mercury will be seen passing behind the spacecraft structural elements.

These will be the first close-up pictures of Mercury since the Messenger orbiter mission ended in 2015.

Ispace’s 3rd lunar lander to be larger, built entirely in U.S.

Capitalism in space: The private Japanese company Ispace announced yesterday that its third lunar lander will be larger (to provide more payload space for customers) and built entirely in U.S. (to better garner NASA contracts).

The lander, being developed by the company’s U.S. office in Denver, will fly as soon as 2024 on the company’s third mission to the moon.

A major difference in the new design, company officials said in interviews, is the payload capacity. While the lander ispace is building for its first two missions in 2022 and 2023 can carry 30 kilograms of payload to the lunar surface, the new lander will have a payload capacity of 500 kilograms to the surface. It will also be able to deploy an additional 2,000 kilograms of payloads to lunar orbit.

The company is also hardening the lander to survive the two week long lunar night.

The decision to shift operations to the U.S., and partner with U.S. companies General Atomics and Draper, makes Ispace a viable competitor for later NASA contracts, which in turn can encourage other privately funded payloads to sign on.

Japan to attempt sample return mission to Martian moon

Japan’s space agency JAXA today announced that it will launch in ’24 an unmanned probe to the Martian moon Phobos that will return a sample to Earth in ’29.

The plan is to bring back about 10 grams of material.

If launched as planned, Japan will beat everyone in getting the first samples back from Martian space. China says it hopes to grab samples from Mars itself by 2030, while the U.S. and Europe hope to launch a mission to return the Perseverance cached samples sometime in the 2030s.

Japanese scientists complete inventory of Ryugu asteroid samples

In a press conference yesterday the Japanese space agency JAXA announced that scientists have completed their inventory of the samples brought back from the asteroid Ryugu by the Hayabusa-2 spacecraft, and are now ready to begin distributing those samples to scientists around the world for more detailed research.

JAXA has cataloged the soil samples brought back by Hayabusa 2 last December, by size, color and shape. From now, 269 researchers from 14 countries, including Japan and the United States, will conduct an in-depth analysis of the soil’s structures and components over the course of about a year.

As expected, the inventory found the samples had a large amount of hydrogen, oxygen, and carbon atoms. Even before Hayabusa-2’s arrival, Ryugu had been catalogued as a “hydrated” asteroid, which means it was thought to contain a lot of hydrogen and oxygen, the basic elements of water. The inventory has now confirmed this.

Japan passes law protecting property rights in space

Japan’s legislature on June 15th approved a new law designed to protect the ownership of the resources private entities extract for profit in space.

Japan’s legislation is similar to provisions in the Commercial Space Launch Competitiveness Act, passed by the U.S. Congress and signed into law by President Obama in 2015. That law grants U.S. companies rights to resources that they extract, but not property rights to celestial bodies, which would run afoul of the Outer Space Treaty. Luxembourg and the United Arab Emirates have since passed similar legislation.

All four countries are signatories of the Artemis Accords, which endorses the ability to extract and use space resources. “The Signatories affirm that the extraction of space resources does not inherently constitute national appropriation under Article II of the Outer Space Treaty, and that contracts and other legal instruments relating to space resources should be consistent with that Treaty,” the accords state.

Both Russia and China oppose such legislation, as well as the Artemis Accords, which have now been signed by eleven countries.

What this growing alignment of opposing sides means for future space operations by private companies is unclear, though it suggests these two countries will not honor those private property rights, which in turn suggests this legal disagreement is eventually going to lead to physical conflict in space.

Lockheed Martin and General Motors partner to design manned lunar rover

Capitalism in space: Lockheed Martin and General Motors announced yesterday that they are partnering to design a manned lunar rover, intended for sale to NASA’s Artemis program as well as any other manned lunar missions anyone else should decide to fly.

Lockheed and GM don’t have a NASA contract to build the LTV [Lunar Terrain Vehicle]; the agency hasn’t awarded any such deals yet. But the companies are positioning themselves to be in the driver’s seat when such decisions are made — and when other customers may come along as well.

Obviously the first customer for this moon buggy would be NASA for Artemis. Nor is this the only manned rover being planned. Toyota and Japan’s space agency JAXA are also partnering to build one.

The decision by NASA to use Starship as its lunar lander however has made such a project much more viable. Unlike the lunar landers proposed by Blue Origin and Dynectics, Starship has the payload capacity to carry such things to the Moon, right off the bat. Thus it makes sense now to start designing them and offering them for sale. We should not be surprised if other car manufacturers start proposing their own manned rovers.

Moreover, Starship’s potential also means these rovers could be purchased by others for work on the Moon. If anyone besides NASA decides to hire SpaceX and Starship for their own lunar missions, the Lockheed Martin/GM LTV can also be sold to them. So can the Toyota rover. So could one built by Ford or Mazarati.

Isn’t freedom and capitalism wonderful? Instead of a half century of the nothing that international cooperation and government control brought us in space, private enterprise is suddenly in a burst opening the entire solar system to the world. And don’t expect the pace to slow.

UAE hires Japanese company as partner for its ’22 lunar rover mission

Capitalism in space: The United Arab Emirates (UAE) has chosen the private Japanese company Ispace to provide the lander bringing its Rashid rover to the Moon in 2022.

ispace’s 240 kg lander is 2.3 meters tall and 2.6 meters wide. It will be launched by SpaceX, Elon Musk’s rocket company, on a Falcon 9 rocket. Once the iSpace lander is placed in the Earth’s orbit, it will travel to the moon on its own, land and unload the rover.

The lander will use solar panels for power, which will also allow the rover to communicate with Earth. It will also carry a solid-state battery made by NGK Spark Plug, which intends to examine its battery’s lunar performance.

This UAE project is similar but a step up from its Al-Amal Mars orbiter. In that case UAE used its money to have the orbiter mostly built by U.S. universities as they taught UAE’s students how to do it. In this case, UAE engineers appear to be building the rover itself, with the purchased help of others to provide the lander..

Japan’s new H3 rocket is almost ready for launch in ’21

The H3 rocket, jointly made by Mitsubishi and Japan’s space agency JAXA, is almost ready for launch and will be shipped to is launch site shortly for a launch later this year.

According to the link, it will cut the cost of launch by half when compared with Japan’s H2A rocket. They hope this cost reduction will garner them international customers, though I wonder as the rocket is not reusable. To get those international customers they have done something interesting. Rather than putting “Nippon” on the side of the rocket, which is what the Japanese call their country, they have put “Japan” on it instead.

U.S. and Japan formalize partnership on Gateway

NASA announced yesterday the signing of a formal agreement between the U.S. and Japan detailing exactly how the two countries will partner in the building of NASA’s lunar space station Gateway.

Under an arrangement with Northrop Grumman, Japan also will provide batteries for the Gateway’s Habitation and Logistics Outpost (HALO), the initial crew cabin for astronauts visiting the Gateway. Additionally, Japan is investigating enhancements to its HTV-X cargo resupply spacecraft, which could result in its use for Gateway logistics resupply.

…The agreement also marks NASA’s intent to provide crew opportunities for Japanese astronauts to the Gateway, which will be determined following additional discussions, and documented in a future arrangement.

Japan is one of the seven countries that has also signed the Artemis Accords, which covers the legal and international rights under the project. This new agreement is more technical in nature, outlining who will do what during construction.

Of course, much of this assumes that money will be forthcoming from Congress for Gateway. Right now that budget does not really exist, and its allocation remains quite uncertain.

Hayabusa-2 begins journey to two asteroids

On January 5, 2021, after successfully delivering its samples of Ryugu to Earth, Hayabusa-2 fired up its ion engines and began its ten-year journey to two different asteroids.

Hayabusa2’s first extended-mission destination is the roughly 2,300-foot-wide (700 meters) asteroid (98943) 2001 CC21, which the probe will fly by at high speed in 2026, if all goes according to plan. A more in-depth rendezvous with yet another space rock, 1998 KY26, is scheduled to follow in 2031.

In a previous post I had mistakenly left out the first target asteroid. However, their primary target remains the tiny 100-foot-wide 1998 KY26, since it is so small. This will be the first close-up view of such a small asteroid, in space. Since such asteroids are many, it will tell us much about the make-up and history of the solar system.

First look at Ryugu samples

Japanese scientists have taken their first look at the Ryugu sample material brought back by Hayabusa-2 and found they resemble charcoal.

The samples Japanese space officials described Thursday are as big as 1 centimeter (0.4 inch) and rock hard, not breaking when picked up or poured into another container. Smaller black, sandy granules the spacecraft collected and returned separately were described last week.

…The sandy granules the Japan Aerospace Exploration Agency described last week were from the spacecraft’s first touchdown in April 2019.

The larger fragments were from the compartment allocated for the second touchdown on Ryugu, said Tomohiro Usui, space materials scientist. To get the second set of samples in July last year, Hayabusa2 dropped an impactor to blast below the asteroid’s surface, collecting material from the crafter so it would be unaffected by space radiation and other environmental factors.

Usui said the size differences suggest different hardness of the bedrock on the asteroid. “One possibility is that the place of the second touchdown was a hard bedrock and larger particles broke and entered the compartment.”

The analysis of these samples has only just begun. Dating them is likely next, and that will probably reveal some startling results.

Subaru Telescope photographs Hayabusa-2’s next target asteroid

In order to better constrain its orbit, the Subaru Telescope in Hawaii has obtained new photographs of Hayabusa-2’s next target asteroid, 100-foot-wide 1998 KY26.

This asteroid is predicted to approach to within 0.47 AU of Earth in mid to late December 2020, giving us a rare opportunity that comes only once every three and a half years. However, the diameter of 1998 KY26 is estimated to be no more than 30 meters, and thus its brightness is so dim that ground-based observations of the asteroid are difficult without a very large telescope.

The observations with the Subaru Telescope were conducted upon the request of the Institute for Space and Astronautical Science (ISAS), JAXA. And as a result, 1998 KY26 was photographed in the direction of the constellation Gemini as a 25.4-magnitude point of light with a measurement uncertainty of 0.7 mag. The positional data collected during these observations will be used to improve the accuracy of the orbital elements of the asteroid. Similar observations were conducted with the Very Large Telescope (VLT) of the European Southern Observatory (ESO).

If all goes right Hayabusa-2 will rendezvous with 1998 KY26 in the summer of 2031.

Scientists confirm ample Ryugu material in first Hayabuse sample chamber

Japanese scientists have opened the first chamber that stored the Ryugu asteroid samples obtained during its first touch-and-go sample grab, and confirmed that it holds ample material.

They also noted that the chamber itself contained gas from the asteroid as well.

The Japan Aerospace Exploration Agency (JAXA) has confirmed that the gas collected from the sample container inside the re-entry capsule of the asteroid explorer, Hayabusa2, is a gas sample originating from asteroid Ryugu.

The result of the mass spectrometry of the collected gas within the sample container performed at the QLF (Quick Look Facility) established at the Woomera Local Headquarters in Australia on December 7, 2020, suggested that the gas differed from the atmospheric composition of the Earth. For additional confirmation, a similar analysis was performed on December 10 – 11 at the Extraterrestrial Sample Curation Center on the JAXA Sagamihara Campus. This has led to the conclusion that the gas in the sample container is derived from asteroid Ryugu.

They think that this gas must have outgassed from the samples themselves. I suspect it was released either during the long journey or when the samples were subjected to the high accelerations and impact during its return to Earth. Research is going to have to try to pin this down, however.

They plan to open the two remaining sample chambers containing material sometime next week.

Scientists confirm Hayabusa-2’s return capsule brought back material from Ryugu

Based on their first observations of the return capsule from Hayabusa-1, Japanese scientists yesterday confirmed that it successfully has returned material from the asteroid Ryugu.

JAXA said in a statement that they observed the sandy material at the entrance of the collection chamber, but have yet to look inside to see if more asteroid dust is lurking there. It is only the second time that scientists have returned material from an asteroid.

This find in the entrance portends a gold mine of material in the collection chamber itself.

Pearl Harbor: The Last Word

A evening pause: On the anniversary of Japan’s unprovoked sneak attack on the United States, let’s hear what it was like to be a sailor on the U.S. battleships sunk during that attack, from interviews recorded four years ago for the 75th anniversary of the attack.

And did I mention it was an unprovoked sneak attack? The Japanese of that time brought the war upon themselves. Hiroshima and Nagasaki was their fault, not ours.

I wonder, would today’s Americans have the will to win, for freedom and the rule of law, as 1940s Americans did? Based on our response to 9/11, I think not. Based on our terror of a flu-like illness today, I know not. The tragedy of this is beyond words.

Hayabusa-2’s samples from Ryugu land in Australia

The return capsule carrying the asteroid samples grabbed by Hayabusa-2 from Ryugu successfully parachuted down in the outback of Australia today.

Officials from the Japan Aerospace Exploration Agency, or JAXA, confirmed shortly after 1 p.m. EST (1800 GMT) that the Hayabusa 2’s nearly 16-inch (40-centimeter) sample carrier landed in Australia. Touchdown likely occurred several minutes earlier.

Recovery teams dispatched via helicopter began hunting for the 35-pound (16-kilogram) capsule using estimates of its landing site derived from a radio beacon signal. Mission managers expected it could take several hours to find the capsule and recover it. The landing occurred before dawn in Australia.

Since the article above was posted the capsule was located, and it was found much quicker than first expected.

This was the second sample return mission by the Japanese. The first, Hayabusa-1, successfully returned its capsule in 2010, but because of many technical problems during the mission it only brought back a few microscopic samples. In fact, the technical problems were so bad it was really a miracle the capsule came back at all.

Hayabusa-2 however has been a complete success, showing that they learned from the first mission and applied those lessons to the second.

Problems discovered in new Japanese H3 rocket engine

Engineers at Mitsubishi have discovered technical problems in the engine for Japan’s new H3 rocket, forcing its first test launch to be delayed into 2021.

The Japanese space agency JAXA told SpaceNews that problems were found with the new LE-9 engine’s combustion chamber and turbopump. “Fatigue fracture surfaces were confirmed in the apertural area of the combustion chamber inner wall and the FTP blade of the turbo pump,” according to a JAXA spokesperson.

JAXA and Mitsubishi Heavy Industries (MHI), the prime contractor for the H3, were aiming to hold the inaugural launch by the end of 2020 before the discovery of issues in May. However engineers testing the LE-9 cryogenic liquid hydrogen and liquid oxygen engine for the H3 first stage encountered a potential issue back in May. This led JAXA to announce in September that the first flight would slip to some time in Japanese fiscal year 2021, beginning April 1, 2021. The rocket’s second launch likewise slipped to Japanese fiscal year 2022.

The H3 is intended as a cheaper and more competitive version of Mitsubishi’s H2 rocket, which has failed to garner much business outside of Japanese government launches because of its cost. That the H3 isn’t being built to be reusable however means it will likely not achieve that goal, as it will not be able to lower it enough to compete with SpaceX.

This launch delay further weakens its ability to compete, as it gives more time for other cheaper alternatives to hit the market.

Mercury probe BepiColombo probe flies past Venus

Venus during BepiColombo fly-by
Click for full image.

The two-pronged European and Japanese probe BepiColombo today has completed its first of two fly-bys of Venus on its way to an arrival at Mercury in 2025.

The image to the right is one of 64 taken during the fly-by. The science team has created a movie from those images, showing Venus slide past as the spacecraft slewed to view it. During the fly-by the instruments on board its Japanese and European orbiters, both of which will separate and operate independently once they reach Mercury, gathered data of Earth’s sister planet.

The spacecraft still needs one more Venus fly-by plus six past Mercury to get it on a trajectory that will put it in orbit around Mercury. It has also already completed one fly-by past Earth in this complicated route.

Ryugu, like Bennu, appears to have rocks from other asteroids

Japanese scientists today announced that 21 rocks identified by Hayabusa-2 on the asteroid Ryugu have a composition that suggests they were formed on another asteroid.

Although Ryugu’s surface is uniformly dark [because it is a C-type asteroid], the scientists behind the new research found numerous boulders scattered across the asteroid that were 1.5 or more times brighter than their surroundings — that is, they reflected at least 50% more light than most of the rest of Ryugu. This contrast made the researchers suspect these boulders may have come from outside the asteroid.

By analyzing the spectrum of light reflected off 21 of these boulders, the scientists deduced they were made of minerals known as anhydrous silicates. Prior studies have suggested that such water-poor, silicon-rich rocks make up silicaceous or S-type asteroids, the most common kind of asteroid found in the inner main asteroid belt. The brightness of these boulders also matches the brightness of S-type asteroids.

This result compliments the result yesterday from scientists studying Bennu with OSIRIS-REx, and was in fact released at the same time. Both asteroids apparently contain material from other asteroids, suggesting that asteroids in their initial formation (as rubble piles) are routinely a mixture of material from many asteroids, thrown out during impacts and then recaptured.

Japan chooses Hayabusa-2’s next asteroid target

The new colonial movement: It appears that Japan has chosen the next asteroid that its probe Hayabusa-2 will visit in 2031, after it releases its samples to Earth in December from Ryugu.

Japan’s Hayabusa2 space explorer will aim to probe the asteroid “1998KY26” located between the orbits of Earth and Mars in 2031 after completing its current mission of collecting samples from another asteroid, the country’s science minister said Tuesday.

It is hoped Hayabusa2 will approach the ball-shaped asteroid, which has a diameter of around 30 meters and rotates about every 10 minutes, in July 2031, Education, Culture, Sports, Science and Technology Minister Koichi Hagiuda said.

It will not obtain samples from this second asteroid, only observe it close up by camera.

Japan delays launch of new rocket one year

Capitalism in space: Because of a problem discovered in the development of its new first stage engine, Japan has now delayed the first launch of its new H3 rocket one year, to ’21.

Mitsubishi is building the rocket for Japan’s space agency JAXA, Since you design and build your rocket around your rocket engines, having a problem with that rocket engine puts a serious crimp on construction. Thus, identifying and dealing with such engine issues early in development is wise.

Still, Japan continues to lag behind the other space-faring nations in the development of its space industry.

Private Japanese lunar lander redesigned, flight delayed one year

Capitalism in space: The privately financed Japanese lunar landing company Ispace has redesigned its lander and delayed the first flight by one year, to 2022.

Since a preliminary design review in 2018, ispace has reduced the size of Hakuto-R. Previously 3.5 meters high and 4.4 meters wide with its landing legs deployed, the lander is now 2.3 meters high and 2.6 meters wide. The spacecraft’s mass has decreased from 1,400 to 1,050 kilograms, primarily by reducing the amount of propellant on board.

A smaller lander is less expensive to develop, said Ryo Ujiie, manager of the lander system engineering group at ispace, during a call with reporters July 30. It also reduces the size and complexity of the landing legs. The spacecraft will use a different trajectory to go to the moon, employing a low-energy transfer orbit that requires less propellant but takes roughly twice as long as previously planned. “We had to pick a more propellant-efficient orbit” given the reduction in propellant, said Chit Hong Yam, manager of the mission design and operations group. “We’re confident that, with enough checking, we should be able to execute this orbit.”

While the overall lander is smaller, it still maintains a payload capacity of 30 kilograms. Once on the surface, likely at one of several mid-latitude sites on the moon under consideration by ispace, it will operate for 12 days.

That first flight will launch on a Falcon 9. The company raised $95 million in private capital in 2017, and still plans a second lander launch in 2023.

After releasing its Ryugu samples Hayabusa-2’s mission will continue

Japan’s space agency JAXA has revealed that it is looking at two fast-spinning asteroids as possible destinations for its Hayabusa-2 spacecraft after it has dropped off its samples from the asteroid Ryugu on December 6.

The candidate asteroids on the agency’s list are asteroid 2001AV43 which Hayabusa2 would reach in November 2029 after flying by Venus, and asteroid 1998KY26 which the probe would reach in July 2031 after passing by another asteroid.

JAXA says both asteroids are rotating on their axis once every 10 minutes. The high-speed spinning indicates that the asteroids’ inner structures are likely different from that of asteroid Ryugu on the first mission, which consists of pieces of rocks.

The spacecraft will no longer have the equipment for returning additional samples, but everything else is functioning and it has the fuel.

UAE’s Hope Mars Orbiter successfully launched

The new colonial movement: The United Arab Emirates first interplanetary probe, its Hope Mars Orbiter, was successfully launched by a Mitsubishi H-2A rocket today from Japan, and is now on its way to Mars.

It will arrive in February 2021, when it will attempt to inject itself into orbit, where it will then be used to study the Martian weather.

The leaders in the 2020 launch race:

16 China
10 SpaceX
7 Russia
3 ULA
3 Japan

The U.S. still leads China in the national rankings, 17 to 16.

Privately-built Japanese smallsat successfully tests new technology

Capitalism in space: A privately-built Japanese smallsat has successfully tested seven new technologies on a six-month long mission that was launched in January on Japan’s newest low-cost Epsilon rocket.

For the first time, the Japanese space agency turned over development of one of its satellites to a startup. Axelspace Co. developed RAPIS-1 for the agency is a short time period, going from design to launch in only about two years, the agency said. The satellite bus features a standardized interface that made attaching instruments and equipment easier. The mission equipment and bus were independently designed to prevent failures of the former from affecting the latter, JAXA said.

The article at the link provides details about the technologies tested, all of which increase significantly the capabilities of smallsats to replace standard larger and heavier satellites.

Interstellar suborbital launch ends in failure

Capitalism in space: A suborbital launch attempt today by Interstellar, a private Japanese smallsat rocket company, failed one minute into flight, with the rocket falling into the sea.

It apparently failed at about 12 kilometers elevation, when it began tumbling. I have embedded the video of the launch below the fold, cued to just before liftoff.

This was their fifth launch attempt. Only the third launch reached their target altitude of 100 kilometers.
» Read more

Japan launches HTV cargo ship to ISS

Japan today successfully launched to ISS the last of its first generation HTV cargo ships.

This was the ninth such cargo ship launched by Japan. The mission was also the last launch of Mitsubishi’s H-2B rocket, Japan’s most powerful. It is being replaced with the H-3 rocket, which they hope to fly for the first time before the end of this year. They also hope that the H3 will be cheaper to operate, and will allow Mitsubishi to garner some commercial business with it, something they failed entirely to do with the H-2B.

This was also Japan’s second launch in 2020, which means they remain outside the leaders in the 2020 launch race:

8 China
6 SpaceX
6 Russia
3 ULA

The U.S. continues to lead China 11 to 8 in the national rankings.

Evidence suggests Ryugu was once closer to Sun

The uncertainty of science: Spectral data collected of the surface of Ryugu by Japan’s Hayabusa-2 probe suggests that the asteroid once spent a period of time much closer to the Sun.

The combined data show an oddly striated world. Ryugu’s equator and poles are tinged blue and are brighter compared with its darker, reddish mid-latitudes. These color differences wouldn’t be obvious to the human eye, although the brightness changes might be.

…As Tomokatsu Morota (University of Tokyo) and colleagues write in the May 8th Science, Ryugu’s boulders likely start bluish. Then a combination of solar wind exposure, meteoroid impacts, and solar heating reddens them. This redder stuff migrates to the asteroid’s mid-latitudes over time, because topographically those are the lowest on Ryugu’s surface. That movement leaves the higher equator and polar regions relatively bluer and brighter.

Based on this data, the scientists posit that Ryugu was closer to the Sun from 800,000 to 8 million years ago, and that the evidence also suggests that the asteroid is only at most 17 million years old.

To put it mildly, there are great uncertainties to these conclusions.

1 2 3 4 5 6 14