rogo japanese english


このページのコンテンツには、Adobe Flash Player の最新バージョンが必要です。

Adobe Flash Player を取得

Debris's Study

In this page , we explain a private enterprise, space institutions and universities try to solve the problem about space debris.
If you click on the left navigation bar, the page can change one you want to see.

As you all know, space debris are very dangerous because they are rapidly increasing. Nevertheless, in the fact there is no definite solution to the problem. why?

The reason is quite lack of expense. It for space debris is 0.2 percent of whole space it or less than.


As you see, three country, Russia, U.S, China, occupy more than 90 percent of all space debris.

However, they think they contribute to developing so the country have blessing of that should pay money.

While other countries think they do not pollute space so three

Countries should pay money. If they go on like this, they are getting nowhere. Thus, the solution about space debris is keeping slow progress.

The Thing Researched

Japan and countries around world study about Space Dabris.
By looking study which companies and universities do,let's make our opinion about solving Space Debris.

Get Rid of Debris

You will understand that many Space Debris are occuring because space development is running.

If humankind stopped space development, far from decreasing Space Dabris , they would crease because of Kessler Syndrome.
Fundamental solving about Debris problem needs that we are removing they.
This is grouped,

・Boy of ASTROSCARE company
・Electro conductibility tether


 Many Space Debris are floating in the space.

However,if we leave them, it has danger that they caused extensive damage to satelites and ISS.

Every countries catalog ther satelites and Space Debris and observe where they are and avoid collisioning them.
Moreover,they simulate Debris environment.In Japan,they study about observing Debris.

・Mihoshi space guard center
・Model about fluctuation of Debris .


Size of Debris are 10cm or less are too small to observe .
Probability that the minute Debris collision the satelites is very high so the satelites have syastems defending ther exterior walls.

However,various problems,for example spalling, hide only protecting ther exterior walls.
What kind of measures should we do?
If you want to know about ther system , please look bottom.

・Structures of ISS about defending them
・System of spalling

Stopping Appearance

Since problem about Space Debris came to light,efforts, "Don't make Space Debris" are done by aerospace exploration around world .
It is impossible to launch the satelites without making Debris.
But we reuse part of the satelites and to prevent them from happening breakup is prevent them from happenning the minute Debris.
The way of launching rockets have 5 stage,

①The rocket ascendes to some degree and solid rocket booster is separated.
②It do more and the air become thin.So payload fairings don't need and they are separated.
③The first stage of rocket is separated.
④The second stage of rocket is separated.
⑤It go in set orbit ,for example geostationary orbit.

Above all,that we collect"parts are separated" with parachute and reuse them is good.

This can not only prevent them from making Debris but also decrease amount of money of space development.
However, there are many boosters which can not collect and they become Space Debris.
The accidents that fuel which boosters have exploded happened many times.

Because the rockets which don't do measure are very dangerous,it is necesaliy to solve rapidliy about this problem.

Researches in Companys

Astroscale Company


ASTROSCARE is the space business company has base in Singapore.

Japanese business worker,MItunobu okada want to change how to solve Space Debris problem.


Mitsunobu Okada(Courtesy of ASTROSCALE)

To break down the current Space Debris problem,he established ASTROSCARE whose business purpose is removing Space Debris in May,4th,2013.

They study and develop removing Space Debris system (ADR).
Through this,they want us to know about space environment problem.

They want to become mediator which private enterprise engage in space
development and has "changing about space more close" as ther mission.

The Strategy of ASTROSCARE

ASTROSCARE narrowed down the target to relatively big size Debris in the amount of 20,000 Debris.

Mr.Okada think the idea that the sanination is called "Mother Ship" from launched rocket make Space Debris aproach and it launch "Boy"that it is slave and glue target.

Grueing "Boy" pushes Spase Debris and it makes Debris rush into the atmosphere and Debris and "Boy" burn by compression heat.

ASTROSCARE suppose that first launch is in 2018.
The member will take part in this project aren't announced but including
Japan, 4 Universities and 2 companies will study and it will be global syastem.


This is the "Boy".
"Boy"sticks Space Debris whose size is more bigger than "Boy".
"Mother Ship" releases "Boy"s one by one and "Boy" takes Space Debris to the atmosphere.



All debris make the rounds of the earth .
They use this nature.

「Boy」 push the debris to be slowed down.
They can bring debris makeing the rounds of orbit since 100 years ago only two days .


This is the moter ship. Mother ship has six Boys .

Our Opinion

■Private venture companies challenge space debris !

As you have known from the page of "companies", there are only a few companies which makes space debris removal an activity contents.

As far as we know, there is only one company who does that whose name is ASTROSCALE.
There are many other cases that private venture companies who relate to this activity, but that is only a way to cooperate, and they are not putting on focus to space debris removable. For example, a space agency like JAXA or NASA.

In other words, space agencies like JAXA and NASA asks a private company like Mitsubishi Heavy Industries to make a machine or a tool so that they can get rid of space debris in the way they are thinking of.

That means that the private company which was offered the work is surely concerned with getting rid of space debris, but it isn't actually focusing on it.

ASTROSCALE is one of the small number of companies which is focusing on getting rid of those space debris.

The representative of ASTROSCALE whose name is Miteunobu Okada, was not studying about space, but was belonging to the department of agriculture, but that man is now making the most of his experiences, and suddenly came out to the business world of space industry.
Since the company was made, it has been in black.

It may be able to do something even we have no knowledge about space, but a specific goal what we want to do and also an idea. br> We don't need the knowledge if we can cooperate with someone who has it, do we?

And we think a person follows a person who has a specific goal.
Space is now watched by many kinds of entrepreneurs all over the world.

Among them, the future always removal of the will will space debris that become a problem,
in terms of maybe the economy, might have an important place the space industry maximum of business opportunities.

Researches in Collage

Kyushu University

Mr.Toshiya Hanada who is professor at Kyusyu University and JAXA study to decrease amount of Space Debris and protect the satelites from Debris.

・Orbital Debris Modeling

Orbital Debris Modeling protect Debris enbironment becoming and evaluate what kind of measures do we to decrease Debris in the future.

If the international rulles to decrease Debris were obeyed, it would be predicted that Debris increase by crashing with Debris and Debris.
These themself multiplication are Confirmed and countries discuss what we have to do.

It can evaluate whether debris can decrease when measures do effectively.

・Analyzing tool

This analyzing tool can analyze risk debris giving damage.

It will be chance to make measures to protect from crashing.

・Support tool preventing from makeng debris

To decrease making debris ,
JAXA sets standard preventing from making decrease.
This proves whether rockets meet the standard.

It can calculate how much fuel need to adpt this standard.

Tohoku University

Tohoku University  Another university also tackles with the problem.
JAXA selected a University-made-satellite FREEDOM as one of the five satellites released from JEM.
FREEDOM, a super micro satellite being made by Tohoku University and Nakashimada Engineering Works Ltd, provides one solution to stop increasing debris.

It is about 1.3kg weight and 10 centimeters side cube. After release from JEM, FREEDOM will expand the thin film in order to re-entry from the orbit into the atmosphere by getting a little air resistance.
This apparatus can make satellites finish its operations without changing debris.

Switzerland Space Center

What's SSC?

Swiss Space Center was established in 2003 at Ecole Polytechnique Fédérale de Lausanne (EPFL), Northern Swiss as a base of space engineering.

Today it has many partners such as Claude Nicollier, the first Swiss astronaut, working as a professor of space science at EPFL now.

SSC sets the goal that it encourages the research and development of space and promotes public awareness of space.

Polluter pays principle

In 2009, "Swisscube", the first Swiss satellite, was launched from SSC.

Swisscube had finished its mission of observing airglow and thus SSC is planning a new mission "CleanSpace One project" to collect it in order not to leave it on the orbit.

Volker Gass, Director of SSC, said, "The person responsible for the mess is also responsible for cleaning it up".

SSC is going on the project as it follows this "Polluter pays principle".

CleanSpace One

Clean space One Clean space one is super small satelite whose scale is 30×10×10cm. It can catch more small debris than noy cathing one. But it has many problems .
For example, it is difficult to recognize and needs compact electric moter .

However, Forcar professor, who is developer of this system sayed that it will succeed because of Switzerland's strong field.

If this two systems succeed, amount of debris will become few number significant.

Researches in JAXA

Conductive Tether

JAXA’s Proposal

We asked JAXA
‘“What is the most effective and cheapest way to make a removal system of space debris ? “

The answer was making space debris system by using an Electrodynamic Tether ( EDT) which is strings has a conductivity.

Authentic Electrodynamic Tether made in Japan!?

What is JAXA's solutions of space debris?
We asked JAXA what JAXA are examining as the most low cost solution of space debris, and they answered . Their answer is"electrodynamic tether"! It is called that technology with a net. What is electrodynamic tether? How they will catch space debris with it?

All of tether made in Japanese?

How to reduce debris with electrodynamic tether.

1, JAXA's Space debris eliminator is launched by rocket.
2, The eliminator is enter orbit.
3, The eliminator approaches the target(space debris).
4, The eliminator attaches it's tether to the space debris.
5, The space debris leave orbit by the tether.
6, The eliminator moves to next target.

As it's name suggests, electrodynamic tether can be conducted electricity. After the eliminator attaches tether to the space debris, the tether be electrified.

By being electrified, interference with geomagnetic field generates Lorentz force(force that particle has electricity). This force makes the target to leave orbit.

What kind of thing is this technology?


Our Opinion

We’ve looked thorough JAXA’s debris remover which is hottest in the world so far.
It has been studying about Tether whole around the world, and we are very proud of space debris remover study and development are supported by Japanese companies.

It’s really serious and hard problem to reduce space debris in space.
International community tends to ignore the fact. In that situation the companies and institution trying to solve the problem which is awesome.

It is good to know what is going on the real world, and we’ve got to think about that.

Measures Taken in The World

Measures Taken in ISS

ISS and Space Debris



In the late 1980s, it find out that debris is menace to ISS. So, ironically, study about debris advanced rapidly. ISS is place to live for many astronauts.
We must solve problems about debris.

ISS reinforces extdrior walls to protect astronauts from crash. It is just whipple bumper.
This mechanism is kinetic energy change heat when debris crash walls of ISS. Hit walls are melted and made holes but debris evaporate. This have little damage.

There are bumper made of aluminum outside of exterior walls made of alloy of aluminum at about 110mm ~120nm intervals.
Owing to this bumper, crashing debris are shattered and we can reduce damage to protective walls.
And pileing insulator up , heat can be sofften. Japanese proving ground , Kibou uses this bumper.

↓this structure
It can protect ISS from debris about 1cm.
In reality , JAXA did experiment and that Kibo has enough protecting performance was proved.
This experiments used 4 mock debris (aluminum balls) and made them crashed walls of Kibo. When how large and how fast debris are crashed, we calculated whether debris make holes by penetration limiting curve.

We forecasted whether debris make holes from penetration limiting curve.
From this result, it was proved that Kibo can stand impact.
But about 1~10cm debris are problems.
They are difficult to observe and there is probability that now shield can't protect ISS.

It is needed studying about improvement of performance and weight saving.


European Space Agency (ESA)released information about ''gossamer'' in 12,23,2013 This official name is ''gossamer deorbit sail''

This is very compact and can open sail which is 5×5m . It cling not used satelites and go into the atmosphere by air resistance. Very light prop made from carbon fiber is installed in sail which is so thin and made from aluminum.

It is possible for gossamer to go into the atmosphere. It is developing in sari university and have finished demonstrative experiment.

We plan to use gossamer at 700km. European standard about debris is we have to do effort satelites leave them orbit not to happen crash accident.
If gossamer cling satelites, they will be able to reenter into the atmosphere after about 25 years.

Professor Rabas said '' This project not only shows that it is possible to design system which make satelites leave from orbit law cost but also connecte goods which have many use values.''

Measures Taken in Propulsion System

It will say that we make idea not to make debris from rocket puropellant and electric circuit.

The preventie plan is way emitting all fuel in the space. But this way will get space dirty.
And fire debris will become new debris.
To solve this problem, development about new fuel is starting. Thus, we bave many problems.

We suggest that more people should know the fact we can live comfortable thanks to satelites and these satelites are making many debris.

We want to move public opinion , increase budget to develop.
By Japan and other countries' technique, more inexpensive fuel will be able to use.

Questions to Universities and Companies!

Ms.Naoko Yamazaki

Questions to Universities and Companies!
Ms.Naoko Yamazaki
We abled to ask Naoko Yamazaki ,who is ex­astronaut her opinion about Space Debris. We: Have you ever ancountered Space Debris ?
Ms.Naoko: They were too small to see.
But there were 20 and more cracks outside space shuttle.
We: Were there any warning to avoid Space Debris?

Ms.Naoko: However I have never experienced,ISS changed the orbit twice of year in 2014.
When Mr.Satoshi Hurukawa stayed in there,Debris were approaching them near about 300km.
It was very near.
It was serious to bump, so they waited in Soyuz(Russian spacecraft) and prepared for coming buck the Earth.
We: We don’t knowsuch a thing. It is very dangerous!
Ms.Naoko: UN and many countries are making the guidelines because of not making more debris. But it hasn’t legal force.
Japan can be the leader about solving Space debris problem.
I want your tenacity very much! (We were nodding.)

We:What do you think that there are no bring force power in guideline decreasing Space debris? Ms.Naoko:It is most important to education.
The so­called world powers are reducing debris because the more debris are increasing ,the more the satelites can't be launched.
Demand about the satelites , especially observation satelites are growing in the world ,but this thought is not penetrate people.
So,I think world wide education is important .
I think UN are opening the workshop and the enlightenment activities are needed and measure solving this problem technicallgood­y.
We:Is Does it mean it is most important to understand about space debris to everyone? Ms.Naoko:Yes.
So, it is great idea to make website to teach space debris.
We:How is it to make the United Nations Space and member nations need obeying the international law ?

Ms.Naoko:Yes,loose law is good to join and mandatory law is good­for­nothing.
It is the dilemma.
To make framework which is easy to join is most important.
We:There is idea that put solving the Earth problems before developping the space,isn't there? Ms.Naoko:Oh,I am always bothered if I get this question.
I think that space development is not only to go to the space but also to solve the problems on the Earth.

I believe we need different point of view to solve global problems.
We must think about this problem concretely.
Therefore, we can refer your activities.
I want to make such announcement place for you and others.
We:Does it link that liberal arts students are worth going to the Space?
Not only science but also many different area people must be interested.



I am graiteful to you for maiking time


Innovative Technology Research Center in JAXA study measures about Space Debris.

Question1:What technique is most inexpensive to get rid of Space Debris?

Answer1:Tether propulsion (tether lead electrically) is studied and developed in JAXA. This system are studied in America, Europe and other countries and it is best to get rid of Debris.

Question2:What technique is most quickly to collect Debris(mass)?

Answer2:We think once per a satellite to get rid of Debris.
So, the more satellites are launched, the more Debris we can collect.
To avoid crash, if we get rid of about 100 Debris , danger in the Space will able to decrease.
So, we study and develope about getting rid of large Debris.

Question3 & 4 : What is problem to get rid of Debris system by robot arms ? How will do they removed?

Answer 3 & 4: It is not easy to use that robot arms system because Debris have various peripherals and we have to avoid them and to control robot arms.
Robot arms also have problems whose cost and weight are large. So, this system is difficult.
But we study and develop new system. Thanks for answerring!

Ritsumeikan University Collision Laborator

We questioned to College of Science and Engineering Department of Mechanical Engineering , Keiko WATANABE Associate Professor .

How do we make the walls protecting from Space Debris?

Most important thing is making structure not only solidly but also absorbing and changing energy of Debris .
We looked around various laboratory . Thanks for answerring.


I am graiteful to you for maiking time

Yokohama National University

Yokohama National University
We questioned Department of mechanical engineering , Jun Sinozuka associate professor.
He is well informed about collision dynamics.
We questioned about space debris.

What is danger of spacedebris?

There more problems of spacedebris than one.
First, you may be misundarstanding, when spacedebris crash something else, the most important thing isn't the mass but density. Almost all somthing man-made are made of metal , so damage becomes so big.

Second, ISS and lockets can defend itself from very small debris, but this system has problems.
When spacedebris crash, the outer wall of them gets a littel damage, and big oscellation spread from a crash point.
The big oscellation could damage the inside of them.
Imagine a construct, when it crash spacedebris, oscellation created rebounds in the wall, and the roof falls down.
This phenomenon is called “spalling”.
This problem is need to be taken safety measure. However, spalling isn't known widely.

There is idea of robot's arms as a solution.
What do you think about this solution.

I think the robots could turn in space.
I hope for creating such a robot.

As an above picture, this is air gun style machine made by Mr.shinozuka for shaving something at a high speed.

He said that ha experiments by using handmade pellets.

Thank you very much for his kindness.