Atmospheric assessment of space activity

Atmospheric assessment of space activity

As of August 2025, over 12,600 active satellites orbit Earth, doubling since 2022. Expectations are for satellite populations to rise to 20-30,000 by 2030 and as many as 100,000 by 2050. Much of this growth is derived from the expansion of so-called mega-constellations, large networks of satellites delivering communications and other services around the world. Unlike traditional missions with long operational lifespans, these constellations introduce a high-throughput cycle of satellites entering and exiting the orbital environment to maintain network integrity and upgrade technology. Currently, 1 or 2 tracked objects re-enter the Earth’s atmosphere every day, with this number set to increase significantly over the next decade. These launches and re-entries release soot and metallic particulates (e.g. aluminium oxide) into the upper atmosphere. These particles may influence climate dynamics by forming stratospheric clouds and accelerating ozone depletion, increasing UV exposure risks. Current data is sparse, relying on costly, infrequent (currently discontinued) missions (e.g. NOAA aircraft). Without long-term and scalable monitoring, climate models and policy decisions lack a reliable evidence base.

This programme will develop proof-of-concept technology demonstrators focused on one or both of the following approaches:

1. Develop and test a portable multi-spectral imaging/spectrographic systems capable of monitoring re-entry events in real time. These instruments will help determine the physical processes occurring during re-entry—specifically whether objects ablate, melt, or fragment, and how these behaviours vary with trajectory, composition, and structural design.  

2. Balloon-borne sample return missions to collect and characterise particulates in the upper atmosphere, providing direct evidence of their physical and chemical properties.

The specific focus will be tailored to the candidate’s background and interests, with flexibility to pursue either a single approach in depth or a comparative study across both. The project will include design, prototyping, and field validation phases.

This project is in partnership with the University of Auckland, New Zealand, and Durham University, offering a unique opportunity to test instrumentation and collect data across both hemispheres. The collaboration supports joint field campaigns, shared access to facilities, and integration with complementary research in atmospheric science and space sustainability.

‍