Tag Archives: Japan

Japan’s troubled space agency




Japanese military satellite damaged during shipping

Japan’s troubled space effort suffered a bad setback when a Japanese military communications satellite was damaged in shipment to its launch site in French Guiana.


Problems with attitude system doomed Hitomi

A series of failures in the attitude system on Japan’s X-ray space telescope Hitomi led to its destruction.

The problem started when the satellite’s inertial reference unit detected Hitomi was rotating around its Z-axis at 21.7 degrees per hour. The spacecraft was actually stable at the time, mission managers from the Japan Aerospace Exploration Agency said Friday. The satellite’s attitude control system commanded Hitomi’s reaction wheels, rapidly-spinning devices which control the pointing of the spacecraft with momentum, to counteract the spin. The action caused the satellite to rotate in the opposite direction as the faulty inertial reference unit indicated, officials said. Momentum accumulated inside the reaction wheel system, and magnetic torquers aboard the satellite were unable to unload the building momentum, which neared the reaction wheels’ design limit.

Hitomi’s computers recognized the dangerous situation and put the satellite into safe hold a few hours later. The satellite tried to stabilize using the craft’s hydrazine-fueled rocket thrusters to aim its solar panels toward the sun. But the trouble was not over, and the spacecraft’s solar sensor was unable to find the sun. Struggling to correct the growing spin rate, small rocket firings inadvertently caused Hitomi to rotate faster due to a bad setting in the thruster system, JAXA officials said.

Japanese Venus probe sends back first science data

In a triumph of engineering, the salvaged Japanese Venus probe Akatsuki has beamed back to Earth its first science data.

After an unplanned five-year detour, Japan’s Venus probe, Akatsuki, has come back to life with a bang. On 4–8 April, the Japan Aerospace Exploration Agency (JAXA) presented the first scientific results from the spacecraft since it was rescued from an errant orbit around the Sun and rerouted to circle Venus, four months ago. These include a detailed shot of streaked, acidic clouds and a mysterious moving ‘bow’ shape in the planet’s atmosphere.

Despite the probe’s tumble around the Solar System, its instruments are working “almost perfectly”, Akatsuki project manager Masato Nakamura, a planetary scientist at JAXA’s Institute of Space and Astronautical Science in Sagamihara, Japan, announced at the Inter­national Venus Conference in Oxford, UK. And if another small manoeuvre in two years’ time is successful, he said, the spacecraft might avoid Venus’s solar-power-draining shadow, and so be able to orbit the planet for five years, rather than the two it was initially assigned.

The timing is also good, since Akatsuki is now the only probe circling Venus, and will be for a number of years, until someone else approves, builds, and launches a mission.

Air Force: Hitomi not hit by space junk

The Air Force has concluded that the Japanese X-ray telescope was not hit by debris, and that its problem was thus likely caused by some internal engineering failure.

What exactly happened remains unclear. Moreover, Japanese engineers still hope they may be able to save the spacecraft, as they are periodically still getting some intermittent signals from it.

Video suggests Hitomi tumbling in orbit

Video taken by an amateur astronomer of Hitomi shows it spinning out of control, another indication that something catastrophic occurred to the newly launched X-ray telescope.

The video shows an object that looks like Hitomi, which lost contact Saturday with the Japan Aerospace Exploration Agency (JAXA), shining and then turning extremely dark in short intervals. The wild changes in brightness might mean its sunlight-reflecting side is moving turbulently. “The fact that it is rotating with extreme variations in brightness indicates that it is not controlled and that some event caused it to begin its rotation,” Paul Maley, a former NASA flight controller who observed Hitomi from the ground in Arizona, was quoted as saying.

Debris spotted near Hitomi

U.S. military observations have detected debris near the Japanese X-ray telescope Hitomi that has failed to respond to communication signals.

The U.S. Joint Space Operations Center on Sunday said it has spotted five objects floating near Japan’s brand new Hitomi X-ray astronomy satellite that lost communication with Earth the previous day. In a Twitter post, the center, which tracks objects in orbit, said it identified five pieces of “break up” debris in the vicinity of the satellite.

None of this sounds encouraging.

No communications with new Japanese X-ray telescope

Bad news: Engineers have not been able to establish communications with Japan’s new X-ray telescope, Hitomi, since it was launched last month.

The JAXA announcement is very terse, and somewhat unclear, as its wording suggests that communications were not scheduled to begin until yesterday, even though the spacecraft was launched February 17. To me that does not sound right. Regardless, failure to establish communications at the beginning of a flight is usually a very bad thing, as it usually means something fundamental failed at launch and is thus difficult to fix or overcome.

United Arab Emirates teams up with Japan

The new colonial movement: The United Arab Emirates Space Agency (UAESA) has signed a cooperative agreement with Japan’s space agency JAXA.

The details are slim, but I suspect it is similar to the recent UAE/India deal and involves the UAE providing some of its oil money in exchange for getting some of Japan’s technical help.

Update: My suspicions were correct. UAESA has purchased launch services from Japan Mitsubishi for its Mars mission, dubbed Hope, scheduled for launch in 2020.

Akatsuki to finally begin studying Venus

After a five year delay because its initial attempt to enter Venus orbit failed, the Japanese probe Akatsuki is finally about to begin science operations.

Its present orbit is less than ideal, passing 440,000km from the planet at its farthest point. That is roughly five times greater than initially planned and means the orbit time is now nine days. The change in orbit has affected the probe’s observation plan. Of its seven planned missions, Akatsuki will be able to complete only one: taking serial images of clouds. Unfortunately, the probe’s five cameras, each capturing images in different wavelengths, including infrared and ultraviolet, will not be able to provide the same resolution at this greater distance. Observing volcanic eruptions on the Venusian surface may also be difficult.

There is an upside to the situation, however. Takeshi Imamura, an associate professor at JAXA’s Institute of Space and Astronautical Science, says the longer orbital period means the probe will be able to collect longer continuous stretches of data.

Considering everything, it is magnificent that Akatsuki will be able to do any science at Venus at all.

Japan looks to private space

The competition heats up: Japan’s legislature is considering bills that would allow for the private launching of Japanese rockets.

Draft bills for the Space Activities Act and Satellite Remote Sensing Act, to be submitted to the regular Diet session from Jan. 4, will require the government to scrutinize launch plans before granting case-by-case permission. Under the Basic Plan on Space Policy set in early 2015, the government aims to expand the size of the space industry to around ¥5 trillion over the next decade. The government would also oblige companies to pay compensation in the event of accidents. Victims would receive government compensation if private operators are unable to cover all the damages, according to the drafts.

Currently, the only entity that has a space program is the state-sponsored Japan Aerospace Exploration Agency.

The proposed laws will probably not work very well, as they they seem to maintain the government’s strong control over everything.

Akatsuki’s Venus orbit confirmed

Venus in ultraviolet by Akatsuiki

Japanese engineers have confirmed that Akatsuki has entered orbit around Venus and can now begin science observations.

The image on the right was taken by the spacecraft’s ultraviolet camera, and clearly shows the as-yet unidentified dark material in Venus’s upper atmosphere. These dark streaks have been seen since the first Venus fly-by in the 1960s, but no observations have been able to determine what the material is that shows up as dark in ultraviolet light.

This success is a triumph for the engineers that operate Akatsuki. Kudos to them!

Roosevelt’s speech responding to the Japanese attack on Pearl Harbor








Success at last for Akatsuki

Five years after the Japanese Venus probe Akatsuki’s main engines failed while trying to put it into orbit, the spacecraft today fired its attitude thrusters and was successfully inserted into orbit.

This is a singular achievement by the Japanese engineers running the mission. They improvised a plan using the thrusters, which were designed to adjust the spacecraft orientation, not its course, and were able to get Akatsuki in an solar orbit that brought it back to Venus.

The launch cost of Japan’s H-IIA rocket

The competition heats up: Yesterday’s launch of Japan’s first commercial payload on its upgraded lower cost H-IIA rocket suggested that they are now a serious player in the competitive launch market. What the earlier articles didn’t tell me was the cost they charge to launch a payload on H-IIA.

This article today states that each launch costs 10 billion yen, which translates to about $80 million. That is about $10 million more than SpaceX charges for its Falcon 9, but is certainly cheaper than many other rocket companies. At this price they have a chance of grabbing some of the launch market, but to really compete they need to cut that cost even more, which the article suggests their next rocket will succeed in doing: “The government is developing a new core rocket named the H3, whose launches are expected to cost only about a half of the H2A.”

They do not say whether H3 will be reusable, but at $40 million per launch it will be the cheapest rocket on Earth. That it is government developed however makes me skeptical they will succeed. We shall see. What is clear, however, is that the competition is certainly encouraging the lowering of cost.

Japan launches its first commercial payload

The competition heats up: Using its H-IIA rocket, upgraded to lower cost, Japan launched its first commercial payload today, putting Canada’s Telestar 12V into geosynchronous orbit.

It is not clear if Japan’s government-run space program can compete. The rocket is built by Mitsubishi, but it appears owned and operated by JAXA, the equivalent of Japan’s NASA. It has also been a very expensive rocket to launch, as for much of its existence it has been like SLS, more dedicated to producing pork jobs than actually competing with other rocket companies. Whether they can upgrade it sufficiently to compete in price with other rockets is highly questionable.

Nonetheless, that Japan is trying to compete is good news. The more competition, the better. The effort alone will produce new ideas, which in turn can only help lower the cost to get into space, thus making it possible for more people to afford it.

Japan’s Venus probe zeros in on Dec 7 arrival

A Japanese Venus research spacecraft, dubbed Akatsuki, has completed all its preliminary course corrections and is ready for a December 7 orbital insertion attempt, the second since the spacecraft’s main engine failed during the first attempt in 2010.



To make this second chance possible, they have spent the last five years improvising. First they dumped the fuel from the now-useless main engine to make the spacecraft lighter so that the attitude control thrusters could handle the maneuvers. Then they used those thrusters repeatedly to adjust the course to bring Akatsuki back to Venus after it zipped past in 2010.

If they succeed in getting it in a useful orbit on December 7, it will be real triumph for these Japanese engineers.

Using fish to study bone loss in weightlessness

A Japanese experiment on ISS, comparing the development of fish in weightlessness with those on the ground, has provided` scientists more information about bone density loss in weightlessness.

Akira Kudo at Tokyo Institute of Technology, together with scientists across Japan, have shown that medaka fish reared on the International Space Station for 56 days experienced increased osteoclast activity – bone cells involved in the re-absorption of bone tissue – likely leading to a subsequent reduction of bone density. They also found several genes that were upregulated in the fish during the space mission. The team generated fish with osteoclasts that emit a fluorescent signal. They sent 24 fish into space as juveniles, and monitored their development for 56 days under microgravity. The results were compared with a fish control group kept on Earth.

Kudo and his team found that bone mineral density in the pharyngeal bone (the jaw bone at the back of the throat) and the teeth of the fish reduced significantly, with decreased calcification by day 56 compared with the control group. This thinning of bone was accompanied by an increase in the volume and activity of osteoclasts. The team conducted whole transcriptome analysis of the fish jaws, and uncovered two strongly upregulated genes (fkbp5 and ddit4), together with 15 other mitochondria-related genes whose expression was also enhanced. Reduced movement under microgravity also has an influence. The fish began to exhibit unusual behavior towards the latter stages of their stay in space, showing motionless at day 47.

What the data mostly confirms is that long-term weightlessness is a bad thing for the development of bones, and not just in humans. Whether scientists can use these results to counter these harmful effects is not clear, however.

Venus probe about to rise from the dead



Japan to upgrade its ISS cargo freighter

The competition heats up: Japan has decided to upgrade its HTV cargo freighter to ISS by cutting its weight by 30% and reducing the cost to build it by half.

Without doubt the success of the U.S. in quickly building two private and relatively inexpensive freighters, Dragon and Cygnus, has influenced this decision. The managers in Japan have realized that the HTV is not efficient and could be streamlined, and they are trying now to do it.

Isn’t competition a wonderful thing?

Japan to the moon!

The competition heats up: Japan’s space agency has announced plans to send an unmanned lander to the Moon, as early as 2018, as part of a longer range plan to explore Mars.

They also intend to use their new Epsilon rocket to launch it.

Gee, I wonder if the successful efforts of India and China to send probes to both the Moon and Mars had some influence on this decision.

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