Researchers from the UAF Geophysical Institute and the University of Calgary in Canada have developed a technique to calculate the distance and angle of approach of a small object to a satellite or spacecraft. The study was published in Physics of Plasmas.
This image, with Earth’s north polar region at center, shows satellites (orange dots) and space debris (pink dots) in orbit through the ionosphere on July 22, 2024. Ionosphere model data were provided by Joseph Huba of Syntek Technologies in Virginia. Image Credit: Paul Bernhardt
The US government is working with a scientist from the University of Alaska Fairbanks to develop a satellite and tools that can identify space debris as small as 1 cm or less than half an inch. Satellites and other spacecraft in low-Earth orbit can sustain damage from debris that is small and currently undetectable from the ground.
Future satellites, including those essential for communication systems, must be equipped with technology that prevents collisions with space debris.
Debris in space moves quickly—roughly 17,500 miles per hour. The impact energy of a 1-cm object moving at that speed is the same as that of a hand grenade or other small explosive.
Space debris, which can take many different forms and sizes, consists of defunct satellites, spent rocket stages, collision fragments, and other man-made items that are no longer needed.
Paul Bernhardt, a Research Professor at the UAF Geophysical Institute, and associates from the University of Calgary in Canada have developed a technique to calculate a small object's distance and angle of approach to a satellite or spacecraft.
The technique is based on their finding that waves are produced when an object in orbit moves through striations, which are naturally occurring plasma disturbances along Earth's magnetic field lines. Plasma, a state of matter that resembles a gas, is made up of positive ions and free-floating negative electrons.
Bernhardt and associates are developing the instruments employing the approach. They are also designing the satellite that will transport the instruments for this preliminary test, which he calls the Space Debris Hunter.
The whole satellite will be dedicated to detection of space debris too small to be seen from the ground.
Paul Bernhardt, Research Professor, Geophysical Institute, University of Alaska Fairbanks
An on-board sensor that simultaneously measures electric and magnetic wave fields would identify signals from the space object and determine the direction of a piece of space debris. Over time, a different sensor would record variations in the signal frequency. The location of the space debris would then be revealed by analyzing these data to determine its direction and distance.
Several measurements of this type are sufficient to predict the future path of the debris. That’s the new science we’re exploring.
Paul Bernhardt, Research Professor, Geophysical Institute, University of Alaska Fairbanks
Bernhardt added that the Starlink system operators perform more than 20,000 collision avoidance actions annually, and this information will enable satellites to be steered away from the debris’s path.
The principal author is Bengt Eliason of the University of Strathclyde in the United Kingdom.
The project is a component of the US government's space debris tracking initiative. It is based on research partially funded by the Intelligence Advanced Research Projects Activity of the Office of the Director of National Intelligence. It was carried out as part of the IARPA Space Debris Identification and Tracking program in cooperation with contractor Blue Halo.
Less than 1% of debris that could endanger a mission is tracked, even though the US debris-tracking program estimates that over 100 million objects larger than 1 mm orbit the Earth. As a result, "there is an increased interest" in tracking small debris, according to the program's website.
Journal Reference:
Eliasson, B. and Bernhardt, A, P. (2025) The generation of whistler, lower hybrid, and magnetosonic waves by satellites passing through ionospheric magnetic field aligned irregularities. Physics of Plasmas. doi.org/10.1063/5.0225399