Detecting Space Debris Collisions and Signals from Earth

Scientists from the University of Michigan have devised a groundbreaking approach to detect small pieces of space junk by capitalizing on the signals generated when they collide.

Current methods of detecting space debris primarily rely on observing objects that reflect light or radar signals. However, as objects decrease in size, it becomes increasingly challenging to capture sufficient sunlight or radar signals for detection from the ground. The limitations of existing technologies mean that we can currently only track objects significantly larger than a cricket ball, leaving the majority of the estimated 170 million smaller debris pieces undetected.

Led by Nilton Renno, a professor of climate and space sciences and engineering and aerospace engineering, the University of Michigan research team proposes a novel solution. Their method involves identifying collisions between space debris fragments and leveraging the electric signals generated during these impactful events.

Trash in space poses a significant threat due to the high speeds at which objects orbit—around 35,000 kilometers per hour. Even a small piece of debris, comparable in size to a plum, can carry momentum akin to a highway car crash. The potential damage to satellites and spacecraft from such collisions underscores the urgency to enhance detection capabilities.

One of the critical aspects of space debris is that collisions often lead to fragmentation, producing smaller pieces. While these collisions can be disastrous, they also provide an opportunity for tracking space junk. When debris collides and fragments, some of it vaporizes into charged gas due to the heat generated by the impact. This phenomenon creates lightning-like energy bursts, which, according to the team's simulations, are strong enough for ground-based telescopes to detect.

The researchers highlight that when two aluminum pieces collide at typical orbital speeds, the resulting electrical burst should be detectable by sensitive ground telescopes. This innovative approach could revolutionize space debris tracking by enabling the identification of debris smaller than one millimeter in diameter.

As space activities continue to increase, the accumulation of debris poses an ongoing threat to both operational satellites and upcoming space missions. The University of Michigan's pioneering research offers a glimpse into a potential solution, opening avenues for advanced technologies that enhance our ability to monitor and safeguard against the hidden perils of space junk. The detection of electric signals resulting from collisions unveils a new frontier in the quest for a cleaner and safer space environment.