Space debris is man-made material in Earth orbit which no longer serves any useful purpose.  Debris objects vary in size from expired satellites as large as a motor car, to microscopic fragments from spacecraft disintegration.  Current scientific consensus is that there are around 500,000 pieces of space debris larger than 1 cm in Earth orbit.  Travelling at 30,000km per hour, space junk as small as 1cm will severely damage or destroy an operating satellite on impact.  The threat to current and future satellites is significant and growing.

EOS Australia, Space Debris Management


EOS, Electro Optic Systems, Defence and Space Technology Company

The basis for all space debris risk mitigation is timely and accurate information about the debris orbits.  This information can be used to avoid collisions in space, and also to plan and execute debris removal programs.

EOS laser tracking technology has been used for over 40 years as the accuracy calibration standard for all space data and catalogues.  Over the past 20 years these calibration systems have been upgraded and expanded to provide cost-effective data for space asset management and debris risk mitigation for all satellite operators, from LEO to GEO. EOS sensors are now deployed to provide accurate and timely space debris data.

EOS space tracking and debris monitoring systems now provide the benchmark for space catalogue acquisition and maintenance, in all key performance indicators:

  • Accuracy.  Space object position can be determined with an absolute accuracy selectable from 1 mm to 1 m, depending on the application.  No other operational space technology offers this accuracy.
  • Sensitivity.  EOS trackers have been validated for tracking objects as small as 6mm in size at 350km range, 5cm at 1,000km and 30 cm at 35,000 km.  This sensitivity addresses over 90% of all collision risk to operational spacecraft.
  • Range.  EOS sensors are able to readily track all orbit heights and regimes from LEO through to GEO and beyond.
  • Cost.  Low cost per space track allows frequent tracking of each object and highly accurate catalogues.

Our expanding network of space sensors provides accurate, specialised catalogues for assessing collision risk in real time.  Conjunction analysis is performed continuously, and the sensor network is re-tasked in real time to allow timely collision prediction using orbit errors smaller than 100m.

In some cases it is not possible to manoeuvre a satellite to avoid a near-certain collision.  For these circumstances EOS is currently fielding a new type of laser tracker which can deliver sufficient laser power to move certain types of space debris to new orbits to avoid collision.  This system cannot damage or fragment debris, but rather provides harmless radiation pressure to move the debris over many seconds of engagement.

This system will commence experimental space operations from late 2019 with initial operational capability planned for 2022.

The video shows a Mount Stromlo laser tracking system with the tracking beam marked in red.  Moving away from earth we see the dense space debris field below 1,000km altitude, and then the sparser debris beyond that distance.  A green crescent shows the object we are tracking and the length of our programmed track of this object.  Any objects coming close to our tracking beam are identified by the code names in green, such that we can turn off the laser if any of them are not space debris, or if our international partners ask us to avoid illuminating certain objects.

A ring of satellites becomes visible at 36,000km altitude, as this is the only orbital ring where satellites can stay above one place on the surface.  Finally we zoom back in and take a quick trip around the planet, where the dark side makes all objects invisible briefly because the sun illuminates the other side.

Contact Electro Optic Systems for more information