Tag Archives: collisions in space

The Traffic Congested Space: Collision Avoidance

On September 3, 2019, it was the first time that European Space Agence (ESA) performed a ‘collision avoidance manoeuvre’ to protect one of its spacecraft from colliding with a satellite in a large constellation,  a SpaceX satellite in the Starlink constellation.  Constellations are fleets of hundreds up to thousands of spacecraft working together in orbit. They are expected to become a defining part of Earth’s space environment in the next few years.  As the number of satellites in space dramatically increases, close approaches between two operated spacecraft will occur more frequently. Compared with such ‘conjunctions’ with space debris – non-functional objects including dead satellites and fragments from past collisions – these require coordination efforts, to avoid conflicting actions. 

Today, the avoidance process between two operational satellites is largely manual and ad hoc – and will no longer be practical as the number of alerts rises with the increase in spaceflight.
 “This example shows that in the absence of traffic rules and communication protocols, collision avoidance depends entirely on the pragmatism of the operators involved,” explains Holger Krag, Head of Space Safety at ESA.   “Today, this negotiation is done through exchanging emails – an archaic process that is no longer viable as increasing numbers of satellites in space mean more space traffic.”

ESA is proposing an automated risk estimation and mitigation initiative as part of its space safety activities. This will provide and demonstrate the types of technology needed to automate the collision avoidance process, allowing machine generated, coordinated and conflict-free manoeuvre decisions to speed up the entire process – something desperately needed to protect vital space infrastructure in the years to come.

Data is constantly being issued by the 18th Space Control Squadron of the US Air Force, who monitor objects orbiting in Earth’s skies, providing information to operators about any potential close approach.  With this data, ESA and others are able to calculate the probability of collision between their spacecraft and all other artificial objects in orbit. 

In August 2019, the US data suggested a potential ‘conjunction’ [collision] at 11:02 UTC on Monday, 2 September, between ESA’s Aeolus satellite and Starlink44 – one of the first 60 satellites recently launched in SpaceX’s mega constellation, planned to be a 12 000 strong fleet by mid-2020.  As days passed, the probability of collision continued to increase, and by Wednesday 28 August the team decided to reach out to Starlink to discuss their options. Within a day, the Starlink team informed ESA that they had no plan to take action at this point.**  ESA’s threshold for conducting an avoidance manoeuvre is a collision probability of more than 1 in 10 000, which was reached for the first time on August 29, 2019 evening.  An avoidance manoeuvre was prepared which would increase Aeolus’ altitude by 350 m, ensuring it would comfortably pass over the other satellite, and the team continued to monitor the situation.

On September 2, 2019, the commands triggered a series of thruster burns at 10:14, 10:17 and 10:18 UTC, half an orbit before the potential collision.  About half an hour after the conjunction was predicted, Aeolus contacted home as expected. This was the first reassurance that the manoeuvre was correctly executed and the satellite was OK.

Since the first satellite launch in 1957, more than 5500 launches have lifted over 9000 satellites into space. Of these, only about 2000 are currently functioning, which explains why 90% of ESA’s avoidance manoeuvres are the result of derelict and uncontrollable ‘space debris’.    In the years to come, constellations of thousands of satellites are set to change the space environment, vastly increasing the number of active, operational spacecraft in orbit.  This new technology brings enormous benefits to people on Earth, including global internet access and precise location services, but constellations also bring with them challenges in creating a safe and sustainable space environment.

This example does show the urgent need for proper space traffic management, with clear communication protocols and more automation,” explains Holger.  “This is how air traffic control has worked for many decades, and now space operators need to get together to define automated manoeuvre coordination.”  As the number of satellites in orbit rapidly increases, today’s ‘manual’ collision avoidance process will become impossible, and automated systems are becoming necessary to protect our space infrastructure.

**On August28th, 2019, SpaceX informed ESA via email that the company did not intend to move the Starlink probe.   At that time, the probability of collision was about 1 in 50,000, according to SpaceX, which is too low to require any preventive action.  The ESA contacted SpaceX daily about its evolving calculations, but the agency did not receive any additional replies after the original email response. SpaceX acknowledges that it failed to communicate due to a bug in its communication system and missed the emails about a higher probability of collision.

Excerpts from ESA Spacecraft Dodges Satellite Constellation, ESA, Sept. 3, 2019 &

A bug in SpaceX’s communication system kept the company in the dark about potential satellite collision, The Verge, Sept. 4, 2019

If You Control Space, You Control Everything: Space as War Domain

The North Atlantic Treaty Organization (NATO) is looking to classify space as a domain for warfare in an attempt to deter China’s growing military power.  If NATO’s proposal succeeds, the international alliance could move forward with the development and use of space weapons.  According to NATO diplomats, the international organization is preparing to release an agreement that will officially declare space as a war domain. This means that aside from land, air and sea, space could also be used for military operations during times of war.

Although NATO’s partner countries currently own 65% of the satellites in space, China is reportedly preparing to launch a massive project that involves releasing constellations of satellites in low Earth orbit.  China Aerospace Science and Industry Corp (CASIC)  is planning to put in orbit 150 or more Hongyun satellites by 2023. Some of these satellites will provide commercial services like high-speed internet while others would be controlled by the Chinese military. These militarized satellites can be used to coordinate ground forces and to track approaching missiles.

“You can have warfare exclusively in space, but whoever controls space also controls what happens on land, on the sea and in the air,” according to Jamie Shea, a former NATO official. “If you don’t control space, you don’t control the other domains either.”

Excerpts from Inigo Monzon , NATO Prepares For Space Warfare By Militarizing Low Earth Orbit, International Business Times, June 24, 2019

The First to Shoot…from Space

North Korea’s preparations to launch a more advanced reconnaissance satellite with a high-resolution scanning capability threaten to push Asia’s space race deeper into the military theater.  The Kwangmyongsong-5 Earth-exploration satellite, likely to be packaged with a separate communications satellite, will technically allow North Korea to transmit data down to the ground for the first time, thus offering real-time intelligence for potential ballistic-missile strikes.

This is well short of the technological capacity needed to deploy orbital weapon systems, but will cause some unease among Asian power-brokers China, Japan and India as they pour money into the last strategic frontier of outer space.  Space programs in Asia have largely been driven by competition for the US$300 billion global commercial transponders market, which is expected to double by 2030 if demand holds.

A shift toward miniature satellites of less than 20 kilograms, mostly used by governments and smaller companies, has drawn nations as diverse as Singapore, Pakistan, Vietnam and South Korea into a field led by Japan and China, with India a more recent player.

Japan placed two satellites in different orbits for the first time on December 2017, displaying a technical edge aimed at reducing launch costs for commercial clients. India announced this week that it had successfully tested a GSLV Mark III rocket that can lift a 4-ton satellite into orbit. In 2017, it managed to launch 104 satellites of varying sizes in just one operation. China has loftier ambitions, including a lunar landing some time in 2018, after sending a roving module down a steep crater on the moon in 2013. About 40 Chinese launches are likely in 2018, mainly to boost communications.  India and Japan are both locked in undeclared space races with China that go well beyond commercial rivalries and have muddied the debate over North Korea’s shadowy aims….

“Militarization” refers to any systems that enhance the capability of forces in a conventional setting, such as intelligence, communications and surveillance. “Weaponization” is the physical deployment of weapons in outer space or in a ground mode where they can be used to attack and destroy targets in orbit.  The United Nations Treaty on Outer Space prohibits the deployment of weapons of mass destruction in space, but the US has blocked efforts to ban space weapons outright. In 2007, Washington said it would “preserve its rights, capabilities, and freedom of action in space.”

Excerpts from  ALAN BOYD,  Asia’s Space Race Gathers Pace, Asia Times, Jan. 6, 2018

A Vacuum Cleaner for Space

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

Space Surveillance Telescope: military use

The most sophisticated space surveillance telescope ever developed is ready to begin tracking thousands of space objects as small as a softball. It’s a boon to space surveillance and science and a new military capability important to the nation and the globe, an Air Force general says.

Developed by the Defense Advanced Research Projects Agency, the Space Surveillance Telescope  (SST) is the most sophisticated instrument of its kind ever developed. It was transferred to the Air Force on Oct. 18, 2016, which has plans to operate it jointly with the Royal Australian Air Force….The Air Force will move the SST to Harold E. Holt Naval Communication Station in Western Australia, operating and maintaining the telescope jointly with the Royal Australian Air Force.The SST also will be a dedicated sensor in the U.S. Space Surveillance Network, operated by the Air Force Space Command.

SST has increased space situational awareness from a narrow view of a few large objects at a time to a widescreen view of 10,000 objects as small as softballs, DARPA says. The telescope also can search an area larger than the continental United States in seconds and survey the entire geosynchronous belt in its field of view –– a quarter of the sky –– multiple times in a night.

Excerpt Advanced Space Surveillance Telescope Has Critical Military Applications, US Department of Defense News, Oct. 22, 2016

How to Make Space Friendly for Military Use

From the DARPA website

The volume of Earth’s operational space domain is hundreds of thousands times larger than the Earth’s oceans. It contains thousands of objects hurtling at tens of thousands of miles per hour. The scales and speeds in this extreme environment are difficult enough to grasp conceptually, let alone operationally, as is required for commanders overseeing the nation’s increasingly critical space assets.

Current [US] space domain awareness tools and technologies were developed when there were many fewer objects in space. Only a few nations could even place satellites in orbit, and those orbits were easily predictable without advanced software tools. That situation has changed dramatically in the past decade with a developing space industry flooding once lonely orbits with volleys of satellite constellations. Despite this much more complex and chaotic environment, commanders with responsibility for space domain awareness often rely on outdated tools and processes—and thus incomplete information—as they plan, assess, and execute U.S. military operations in space.

To help address these technical and strategic challenges, DARPA is launching the first of two planned efforts under the Agency’s new Hallmark program, which has the overarching goal to provide breakthrough capabilities in U.S. space command and control. This first effort, the Hallmark Software Testbed (Hallmark-ST), has as its primary goal the creation of an advanced enterprise software architecture for a testbed for tools that will integrate a full spectrum of real-time space-domain systems and capabilities. The testbed would be used to expedite the creation and assessment of a comprehensive set of new and improved tools and technologies that could be spun off into near-term operational use for the Defense Department’s Joint Space Operations Center (JSpOC) and Joint Interagency Combined Space Operations Center (JICSpOC).

“For example, an intuitive user interface incorporating 3-D visualization technology would present complex information in novel ways and provide commanders with unprecedented awareness and comprehension. An advanced testbed featuring playback and simulation capabilities would significantly facilitate research and development activities, experiments, and exercises to evaluate new technologies for their impact on space command and control capabilities.”

The enterprise architecture would be the backbone of a long-term testbed, the Hallmark Space Evaluation and Analysis Capability (SEAC), anticipated to be located in Northern Virginia.

Excerpts from Hallmark Envisions Real-Time Space Command and Control,  www. darpa. mil, June 17, 2016

See also Hallmark Software Testbed (Hallmark-ST)/Solicitation Number: DARPA-BAA-16-40, June 17, 2016 Federal Business Opportunities

Militarization of Japan: the Fourth Force

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