Tag Archives: space junk

Space Junk Removal

RemoveDebris

The first experiment designed to demonstrate active space-debris removal in orbit reached the International Space Station on April 4, 2018 aboard SpaceX’s Dragon capsule.    The RemoveDebris experiment, designed by a team led by the University of Surrey in the U.K. as part of a 15.2 million euro ($18.7 million), European Union (EU)-funded project, is about the size of a washing machine and weighs 100 kilograms (220 lbs.).

It carries three types of technologies for space-debris capture and active deorbiting — a harpoon, a net and a drag sail. It will also test a lidar system for optical navigation that will help future chaser spacecraft better aim at their targets.

“For this mission, we are actually ejecting our own little cubesats,” Jason Forshaw, RemoveDebris project manager at the University of Surrey, said last year. “These little cubesats are maybe the size of a shoebox, very small. We eject them and capture them with the net.”

“We are testing these four technologies in this demonstration mission, and we want to see whether they work or not,” said Forshaw, referring to the harpoon, net, drag sail and lidar. “If they work, then that would be fantastic, and then these technologies could be used on future missions.”

Some 40,000 space objects — the vast majority of which are defunct satellites and fragments from collisions — are currently being tracked by the U.S.-based Space Surveillance Network. It is estimated that some 7,600 metric tons (8,378 tons) of junk hurtle around the Earth at speeds of up to 17,500 mph, threatening functioning spacecraft, according to a statement from the University of Surrey….

[T]hese same means of capturing debris could easily be used to destroy or otherwise interfere with functional orbital assets [i.e, a functional satellite], most of which are not equipped with a rapid means of evasion or any other form of defense. To a harpoon, net, or drag sail, there is little difference between an out of control hunk of Soviet era rocket and an operational communications or reconnaissance satellite.

Excerpts from BY ALEX HOLLINGS, SpaceX delivers prototype space junk collector to the ISS, but the experiment has serious defense implications, SOFREP.com, Apr. 6, 2018;This Space Junk Removal Experiment Will Harpoon & Net Debris in Orbit, Space.com, Apr. 6, 2018

A Vacuum Cleaner for Space

Catching a rogue satellite. image European Space Agency (ESA)

A Singapore-based venture company aspiring to enter the space business unveiled a life-sized model of a satellite that would retrieve space debris, with which the company plans to conduct a test run in orbit in 2019 and to make commercially viable by 2020.  “Space is filled with trash, and if things continue as they have, space exploration will no longer be sustainable. …

Most orbital debris is old satellites and satellite components. Around 750,000 pieces of space debris at least 1 centimeter in diameter are said to be in near-Earth orbit, and are interfering with countries’ and companies’ efforts to place new satellites. Astroscale’s debris retrieval satellite closes in on dead satellites, and uses magnets to draw them in. The device then enters the atmosphere, bringing the out-of-commission satellite with it, and burns up on re-entry.

For example, in 2009 an out-of-commission Russian military satellite and a satellite launched by a U.S. corporation collided. The International Space Station (ISS) is frequently forced to change course or have its crew members evacuate from their posts. In 2007, China destroyed one of its own satellites with a missile, producing large volumes of orbital shrapnel and triggering international criticism.

Also in 2007, the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) drafted the Space Debris Mitigation Guidelines, which recommends that satellites that are past their usefulness promptly leave their orbits. However, satellites and satellite parts that have already become space debris have uncoordinated trajectories, and because there is no established method of retrieving such litter, various countries and companies have been searching for a solution.

The Japan Aerospace Exploration Agency (JAXA) is working on a plan to attach metallic string to space debris, through which it would pass electric currents and use the Earth’s magnetic field to slow down the debris, and then drop them into the atmosphere. Meanwhile, the RIKEN research institute announced in 2015 that it had devised a method of using high-intensity lasers to slow down “drifting” litter so that they would hurtle into the atmosphere.  Researchers both within and outside Japan have proposed various other ideas, including making space debris attach to operating satellites and catching space debris with nets.

Company to test space-debris-retrieval satellite in 2019, aim to commercialize by 2020, Mainichi Japan, July 15, 2017

How to Wipe Out Space Junk

image frrom http://jemeuso.riken.jp/en/

Half a century of rocket launches has turned the space into a junkyard. Around 3,000 tonnes of empty rocket stages, defunct satellites, astronauts’ toothbrushes and flecks of paint are thought to be in orbit.

Besides being messy, such debris can be dangerous. Anything circling Earth is moving pretty quickly, so collisions between space junk and satellites can happen at closing velocities of 10km a second or more. Large bits of junk are routinely tracked by radar. The International Space Station (ISS), for instance, regularly tweaks its orbit to avoid a particularly menacing piece of litter. But at such high speeds, even a small, hard-to-follow object can do tremendous damage.

Rocket scientists have been pondering how to deal with this problem for years. But a paper just published in Acta Astronautica by Toshikazu Ebisuzaki and his colleagues at RIKEN, a big Japanese research institute, has gone further and proposed actually building a test device.

Dr Ebisuzaki’s plan involves zapping things with lasers. He proposes to point these lasers in the right direction using a telescope intended for a different job entirely. This is the Extreme Universe Space Observatory (EUSO). It is designed to be bolted on to the ISS. From that vantage point it will monitor Earth’s atmosphere, looking for showers of radiation caused by cosmic rays hitting air molecules. Dr Ebisuzaki, however, realised that the characteristics of a telescope designed for this job—namely a wide field of view and the ability to register even fleeting flashes of light—would also be well-suited for spotting small bits of debris as they whizz past the ISS.

Having identified something, the next step is to get it out of orbit—and that is where the zapping comes in… Fire a laser head-on at a piece of space debris for long enough, then, and you can slow it down to the point where its orbit will decay and it will burn up in Earth’s atmosphere.  This idea is not new. But putting lasers into orbit is tricky. Those powerful enough to do the job need lots of electricity and this is hard to deliver with the solar panels from which satellites typically draw their power. Dr Ebisuzaki proposes instead to employ a new, more efficient laser called a coherent-amplification network device, which was developed for use in high-energy physics.

He and his colleagues suggest a three-stage test. The first, with a smaller version of the EUSO and a fairly weedy laser, would serve as a proof of concept. The second would use the actual EUSO telescope and a much more potent laser. Finally, he says, the equipment could be mounted on a purpose-built satellite, from which it would be able to shoot down tens of thousands of bits of space junk every year, thus gradually sweeping the skies clean . 

Orbiting debris: Char wars, Economist Apr. 25, 2015, at 75

The Militarization of Japan: the Fourth Force

China Japan

Japan will add a new division to its military or Self-Defense Forces in 2019, to protect equipment in orbit from space debris as well as other attacks, a source familiar with Japan-U.S. relations said, according to a report by the South China Morning Post.

Japan revised a law regarding its non-military activities in space in 2008, allowing the creation of a “space force,” which will initially be responsible for monitoring dangerous debris floating within close vicinity of the Earth, as well as protect satellites from collisions or attacks, according to the report, which added that the U.S. has been informed of the development by the Japanese Defense Ministry. There are around 3,000 fragments of space debris currently at risk of smashing into reconnaissance or communication satellites around the Earth.  Japan will assist the U.S. military with the information it obtains through this program, and looks to strengthen bilateral cooperation in space, or the “fourth battlefield,” the report said.  The “fourth force” will initially use radar and telescope facilities in the Okayama prefecture that the defense ministry acquired from the Japan Space Forum, which also owns the Spaceguard Center radar facility in Kagamino and a telescope facility in Ihara.

Units from Japan’s Air Self-Defense Force are currently being considered by the defense ministry to make up parts of the new space force. And, the Japanese ministries of defense, education, culture, sports, science and technology, along with the Japan Aerospace Exploration Agency, or JAXA, will jointly acquire the radar and telescope facilities from the Japan Space Forum, a Tokyo-based think tank that coordinates aerospace-related activities among government, industry and academia.

Japan and the U.S. have reportedly been working on a space force since 2007, when China tested its satellite destruction capabilities by launching a missile against one of its own satellites and destroyed it.  In May, at a space development cooperation meeting held in Washington, the Japanese and U.S. governments agreed to increase cooperation in using satellites for monitoring space debris, marine surveillance, and to protect one another’s space operations. Japan also pledged to share information acquired by JAXA with the U.S. Strategic Command.

Excerpts from Alroy Menezes, Japan’s ‘Space Force’ To Protect Satellites In Orbit, International Business Times, Aug. 4, 2014

Just Hit Seeme; the new military satellites of DARPA

Seeme Program Image from DARPA website

The Seeme Program from DARPA website:

DARPA’s SeeMe (Space Enabled Effects for Military Engagements) program aims to give mobile individual US warfighters access to on-demand, space-based tactical information in remote and beyond- line-of-sight conditions. If successful, SeeMe will provide small squads and individual teams the ability to receive timely imagery of their specific overseas location directly from a small satellite with the press of a button — something that’s currently not possible from military or commercial satellites.

The program seeks to develop a constellation of small “disposable” satellites, at a fraction of the cost of airborne systems, enabling deployed warfighters overseas to hit ‘see me’ on existing handheld devices to receive a satellite image of their precise location within 90 minutes. DARPA plans SeeMe to be an adjunct to unmanned aerial vehicle (UAV) technology, which provides local and regional very-high resolution coverage but cannot cover extended areas without frequent refueling. SeeMe aims to support warfighters in multiple deployed overseas locations simultaneously with no logistics or maintenance costs beyond the warfighters’ handheld devices.

The SeeMe constellation may consist of some two-dozen satellites, each lasting 60-90 days in a very low-earth orbit before de-orbiting and completely burning up, leaving no space debris and causing no re-entry hazard. The program may leverage DARPA’s Airborne Launch Assist Space Access (ALASA) program, which is developing an aircraft-based satellite launch platform for payloads on the order of 100 lbs. ALASA seeks to provide low-cost, rapid launch of small satellites into any required orbit, a capability not possible today from fixed ground launch sites.

From the DARPA Website

Raytheon Company was awarded a $1.5 million Defense Advanced Research Projects Agency (DARPA) contract for phase one of the agency’s Space Enabled Effects for Military Engagements (SeeMe) program. During the next nine months, the company will complete the design for small satellites to enhance warfighter situational awareness in the battlespace.  Raython News Release, Dec. 13, 2012