English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In this paper we consider the use of wide field of view radar sensors such asthe Murchison Widefield Array (MWA), a low frequency radio telescope designedfor astrophysics and cosmology, for rapid response observations of the debrisclouds produced by collisions between objects in Earth orbit. With anincreasing density of objects in Low Earth Orbit, including legacy assets usedby the astronomy community over decades, the risk of new debris clouds formingis also increasing. The MWA constitutes a wide field, rapid response passiveradar system and we explore its likely performance in the detection andcharacterisation of debris clouds. In general, astronomy facilities such as theMWA can play a role in protecting the space environment for the future. Inorder to undertake this work, we adapt the NASA EVOLVE 4.0 breakup model,utilising the EVOLVE outputs to produce representative dynamic debris clouds.We find that the MWA is likely to detect a large fraction (>70%) of modelleddebris cloud fragments for collision masses between 100 kg and 1000 kg fororbits in the lower part of LEO, if the MWA can achieve close to optimaldetection sensitivity. Useful detection fractions are still achieved for moreconservative assumptions. The detection fraction of fragments decreases as afunction of altitude and inversely with collision mass. Encouragingly, we findthat the wide field nature of the MWA allows the full evolving debris clouds tobe observed in a single observation, with only $\sim2\%$ of the debrisfragments escaping the sensitive portion of the field of view after 100seconds, for all collision masses and altitudes. These results show that theMWA is an intrinsically useful facility for the rapid characterisation ofdebris clouds, but that work is required to achieve the data processing withinan appropriate timeframe to provide rapid alerts.

Simulations of orbital debris clouds due to breakup events and their characterisation using the Murchison Widefield Array radio telescope