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Detect, Track, and Remediate

The challenge of small space debris

On behalf of

Detect, Track, and Remediate: The Challenge of Small Space Debris

$20,000 USD
Entries Received:
15 days, 5 hours to award
Contest bookmarked successfully!

Challenge Overview and Objective

Innovative solutions are urgently needed to detect, characterize, track, or remediate small debris to ensure the safety and sustainability of space operations.


This competition invites creative minds from around the world to contribute groundbreaking concepts that address the critical issue of small debris in Earth's low-earth orbit (LEO) environment. Low-Earth orbit (often known as LEO) encompasses Earth-centered orbits with an altitude of 2,000 km or less. Low-Earth orbit is considered the area in Earth orbit near enough to Earth for convenient transportation, communication, observation and resupply. This is the area where the International Space Station currently orbits and where many proposed future platforms will be located.
The objective of this challenge is to solicit concepts that offer effective methods for detecting, tracking, characterizing (size, shape, composition), and/or remediating small space debris ranging from 1 millimeter to 10 centimeters in size.
The challenge defines these four capabilities in the following way:
Detecting - the process of identifying and recognizing the presence of space debris, often using sensors and instruments to detect their existence in orbit. Characterizing - the act of gathering detailed information about space debris, including size, shape, composition, and orbital parameters, to understand their properties and behavior. Tracking - continuously monitoring the position, trajectory, and movement of space debris objects to predict their future paths and assess collision risks. Remediating - remediation of debris is any action to reduce the risks associated with orbital debris by moving, removing, or reusing it.  
The focus is on scalable solutions that can address a substantial percentage of the small debris population. Participants are encouraged to think creatively, considering technologies, orbits, and operations that may be less explored but have the potential for significant impact.
Users will register and submit a concept paper addressing a single Challenge domain and build out solutions to address one of the three prize categories as part of the $120,000 prize purse. 
1st place award will be at a minimum $20,000.
Participants may submit a unique concept paper for each problem domain to be eligible for a prize. Each concept paper must be focused on a solution within a single defined domain (Detect, Tracking, Remediation). If a participant wishes to be eligible for multiple awards, they must submit a concept paper into each problem domain.

Detect & Characterize

The current state of the art in detecting and characterizing small space debris involves radar systems, optical telescopes, and data fusion algorithms. These technologies provide valuable information about the size, shape, and distribution of large debris objects; in particular, radar has proven useful to detect objects of size 10 cm and larger[1]. A potential approach involves measuring slight movements in larger objects, such as large space debris or operational satellites, to detect smaller objects that would otherwise go unnoticed;[2] but this is far from the only plan of action. A successful concept paper should provide an overview of the proposed detection system and how it would deliver real-time, accurate data on debris orbits and their physical properties.
Key types of attributes that would help with the detection and characterization of space debris include:
Orbital Data: Precise information about the orbits of debris objects, including position, velocity, and altitude.
Physical Characteristics: Data on debris size, shape, mass, and composition. This helps assess potential impacts and devise appropriate mitigation strategies.
 Key questions to address include:
How many objects are up there?
What are their shapes and compositions?
What are the general characteristics of their orbits? (semi major axis, eccentricity, and inclination)


Tracking small space debris involves continuous monitoring of their positions and trajectories to maintain custody over the objects. In this context, "custody" means that the observing sensor has the capability to view and track the specific space object at any given moment. To build a feasible solution, improvements in sensor capabilities might be necessary for accurately tracking even the smallest debris fragments. Additionally, the development of predictive models that consider gravitational perturbations and atmospheric drag may enhance tracking accuracy. A viable solution, if implemented, should be capable of maintaining custody of small debris objects for a range of prioritized orbits.
In the context of space debris tracking, it's important to note that the methods currently in use represent established approaches, but there's room for innovation and novel solutions, especially when tracking small space debris. Two prominent techniques are "Stare and Correlate" and "Stare and Chase." "Stare and Correlate" involves continuous monitoring of specific regions in space while correlating multiple observations over time to estimate object orbits. In contrast, "Stare and Chase" combines continuous tracking with targeted adjustments, refining trajectory predictions. It allows sensors to focus initially and shift to track objects, enhancing tracking accuracy and collision avoidance. Another method is "Fence Mode," a radar tracking approach sweeping a larger space area to detect various debris. While efficient for broad surveillance, it may compromise accuracy due to atmospheric interference and resolution limitations.
In the context of tracking small space debris, several significant challenges emerge, which can be exceptionally challenging due to small space debris’ low reflectivity. These objects typically have a minuscule radar cross-section, meaning they reflect very little of the radar signal sent to them. Consequently, the signal received by sensors is weak compared to background noise, making it difficult to detect and track these objects.
Additionally, the orbits of small space debris can be dynamic and non-Keplerian; they are influenced by a multitude of factors, including atmospheric drag and space weather effects. Lower altitudes are particularly affected by atmospheric drag, causing objects to gradually lose altitude over time. Space weather, such as solar radiation and geomagnetic storms, can also impact orbital dynamics, introducing unpredictable changes in an object's path. These factors create complexities in tracking and predicting the positions of small debris objects.
Key questions to address:
How well do we know its current orbit?
How certain can we be of how its orbit will change over time?
Can we track the object over a long period of time? 


Remediation of debris is any action to reduce the risks associated with orbital debris by moving, removing, or reusing it. This aspect of the challenge seeks a reduction in the quantity of, or impact risk of Small and Very Small objects in the LEO regime. Current approaches for remediating small space debris include implementing active debris removal missions. One of the main challenges of small space debris remediation is the balance of cost and benefit, as many potential solutions are not of proper scope[3]. A successful solution should offer practical and cost-effective strategies for reducing the overall existing small debris population, mitigating the risk of collisions and maintaining the sustainability of orbital space. 
There are some strategies and concepts that have been developed to address the debris remediation challenge each with strengths and weaknesses. In the “Laser Nudging” method, ground-based or space-based lasers impart momentum to push the object.  Lasers may be a viable solution for small debris, provided their operations can be scaled to a very high frequency of debris item interactions. Experimental methods like debris-slowing using “space dust” have been proposed by deploying micron-scale dust, leveraging the physics of hypervelocity dust/debris collisions to reduce momentum and accelerate the reentry of debris, however the concept has not been demonstrated in a lab[4].  Additionally, the use of a Perimeter-Ring-Truss type of shield system to create a large orbital debris “surface” that, once deployed in a target orbit, would be capable of gathering high-velocity debris has been proposed[5].
Most current remediation strategies for Large (10cm+) orbits involve Deorbiting or Moving techniques that alter the trajectory of the debris, either guiding it to burn up into Earth’s atmosphere or repositioning it into a graveyard orbit. Current remediation solutions may appear viable however they run into scalability challenges when dealing with Small and Very Small pieces of space debris.
In the “Active Tug” method, spacecraft equipped with magnetic or mechanical grapple instruments approach and nudge the object. Active tug is likely not a viable solution to address the small debris challenge due to issues with scaling to remediate the large quantities of debris items, and the fuel cost required to maneuver between hundreds of thousands of pieces. Even if current removal methods were feasible on a case-by-case basis, the cost of such a project would far outweigh any benefits.
A comprehensive solution to the remediation problem domain should propose a method that:
Can be efficiently scaled to handle the large number of debris objects in the 1mm-10cm size range;
Demonstrates technological viability and scientific feasibility;
Balances cost effectiveness of remediation with long-term sustainability;
Ensure that steps toward remediation do not pose risks to current space missions;

Excluded Concepts

This challenge does not seek concepts addressing debris smaller than 1 millimeter or larger than 10 centimeters. Furthermore, solutions that solely improve post-mission disposal plans or mitigate new debris creation are not within the scope of this competition.
[1]Muntoni et. al., “Crowded Space: A Review on Radar Measurements for Space Debris Monitoring and Tracking”. 2021. [2]Williamson, “Improving Orbital Debris Environment Practices Through Examining Satellite Movement Data”. 2020. [3]Colvin et. al.,, “Cost and Benefit Analysis of Orbital Debris Remediation”. [4]Ganguli et. al., “Active Removal of Orbital Debris by Induced Hypervelocity Impact of Injected Dust Grains”. 2014. [5]Foster, “Practical System to Remove Lethal Untracked Orbital Debris”. 2022.

Challenge Background

Earth's orbital environment is marred by a growing population of space debris, colloquially known as "space junk." While larger debris is tracked by the US Space Surveillance Network (SSN), smaller objects with diameters between 1 millimeter and 10 centimeters are not tracked—or detected. The millions of such objects in Low Earth Orbit (LEO) can strike active spacecraft at very high velocities and pose a significant collision threat to both human spaceflight and robotic missions. 

The Problem

The current Surveillance Network cannot effectively track and monitor small debris pieces.  Therefore, innovative solutions are urgently needed to detect, characterize, track, and remediate small debris to ensure the safety and sustainability of space operations. Space debris encompasses defunct satellites, rocket fragments, and smaller debris traveling in Earth's orbit.
Space debris travels at incredibly high speeds, creating a significant collision risk for operational satellites, the International Space Station (ISS), and other valuable assets in orbit. Even a tiny fragment can cause catastrophic damage due to its kinetic energy. As space gets more crowded, the number of expected collisions with Small (1cm - 10cm) and Very Small (1mm - 1cm) space debris will increase tenfold in ten years[1]. Finally, collisions between space debris and operational satellites can generate even more debris fragments, triggering a chain reaction known as the "Kessler syndrome." This could lead to an exponential increase in the amount of debris and make certain orbits unusable. 
The tasks of detecting, characterizing, tracking, and remediating small space debris require solutions that address the physical nature of the problem. The high relative velocity of the objects complicates their tracking, while the sheer number of such objects presents scalability concerns. The challenges and uncertainties in tracking the 18,000 Large space debris objects indicate that minor enhancements to current methods might not be adequate for tracking the 1 million smaller debris objects. 
These small fragments may seem inconsequential, but their cumulative impact can have severe consequences. The ability to detect, characterize, track, and remediate small space debris is imperative to the sustainability of space operations for the following reasons:
Enhancing Collision Avoidance with Debris Detection and Tracking
Accurate detection and tracking help prevent collisions between operational spacecraft and debris, minimizing potential damage and risks. Collision avoidance not only safeguards valuable assets but also plays a pivotal role in ensuring the long-term sustainability of space exploration and satellite operations. 
Improving Spacecraft Design for Shielding using Debris Characterization Data
With detailed data about the size, velocity, and distribution of debris fragments, engineers can design spacecraft components that are more resilient to potential impacts. This informed design approach enhances the overall safety and durability of spacecraft, reducing the risk of damage from even tiny debris particles.
Table 1. Type and Count of Small and Very Small Space Debris[2]
Orbital Location*
Challenge Focus?
Very Small (1mm - 1cm)
LEO(400- 2000 km) and MEO (2000+km)
Small (1cm - 10cm)
LEO (400-2000 km); most concentrated at 750-1000 km
Large** (10cm+)
LEO (400-2000 km); most concentrated at 750-1000 km
(*) orbital debris locations are not uniformly distributed and should be considered as estimates
(**) the identification of “Large” objects is outside the scope of this challenge, which focuses on “Small’ and “Very Small” objects.
[1]Williamson, “Improving Orbital Debris Environment Practices Through Examining Satellite Movement Data”. 2020. [2]Foster, “Practical System to Remove Lethal Untracked Orbital Debris”. 2022.   
In the Files section we included a complete Rules and Requirements document and additional resources for you to review. Please refer to the “Quick Biblio” document to navigate the additional articles and papers that relate to each challenge area.
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Skills Required

Aeronautical Engineering
Aerospace Engineering
Aircraft Performance
Aircraft Propulsion
Aircraft Structures
Aircraft Systems
Computer Vision
Control System Design
Materials Engineering
Materials Science
Mechanical Engineering
Optical Engineering
Remote Sensing
Robot Operating System (ROS)
Robotics and Cognitive Automation
Structural Engineering

Accepted File Formats


Clarification Board
No spam, self-promotion or advertisement is permitted.

Amandeep P.
15 days ago
The competition says it still has about 4 more hours till close, is that not correct?
Contest Holder
15 days ago
The Challenge is now closed. Thank you everyone for participating! We will be in touch with everyone who submitted very soon. Stay tuned for winners announcements!
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Bradley D.
20 days ago
Hi, I just posted my 2 entries, but at least on my screen in the entries tab, instead of showing not my headshot picture there, but is showing part of the first page of my sketches of my entries themselves. I don't think that is right, I don't really want those showing, right? Something went wrong?
Miklos K.
22 days ago
Hello, Is it possible to submit more than one entry for each track? I read the rules and I know it is possible to submit entries for more track, but is it allowed to submit more totally different entries for the same track?
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@Poweredbyfln ..
30 days ago
Missed the webinar? Not a problem! If you couldn't join the webinar on Friday, make sure to watch the recording! It is already available via this link: If you have any questions, make sure to post them on the Clarification Board or email us at and our team will be happy to help you as we approach the submission deadline in 2 weeks.
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Manish S.
30 days ago
Hi , is Singapore a designated country. can i participate if the team leader is from Singapore ?
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Charles P.
30 days ago
I saw this on another site and wanted to check it out, I listed myself as having only one team member but could easily have several. If I think that I could seriously submit a proposal could I then change and add people? I have many years of experience in the space field, working for the US Air Force, working on Space Shuttle and ISS, etc and would be interested in joining a team.
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Ikramul H.
1 month ago
Hello, could Bangladeshi participate in this contest, please?
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Salma M.
1 month ago
I'm from Egypt , Can I participate in this contest? Is there a problem if I cooperate with someone from the United States as a team?
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Anas I.
1 month ago
I'm from Iraq, Can I participate as an individual?

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