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Figure 5. Solar array data, (a) LDEF 4-face mean (i.e. solar array analogue) and model fit; note the debris excess at small sizes, (b) EuReCa solar array data converted to Fmax, and the high reliability TiCCE foil penetration data, (c) HST solar array data, (d) HST solar array data (as in (c) but with an alternative dataset shown).

TiCCE foil data, as we would expect. The solar array data appears consistent with the model, although we might expect a debris excess to be more apparent at the smaller sizes. It is possible that the data might suffer from incompleteness at the small size regime.

Figures 5c-d show the HST solar array data (converted to Fmax) again with the model fits and LDEF 4-face mean solar array analogue. The HST array data are broadly consistent with the LDEF analogue (particularly in Figure 5d using the high magnification SEM data) although as before there might be some incompleteness at small sizes.

The summary of this, is that our understanding of the meteoroid flux, as demonstrated by the fits to the LDEF space face data, is consistent with the (admittedly less well defined) solar array data (and the LDEF solar array analogue and TiCCE foils). However in LEO, debris can add a dominant contaminant component at smaller sizes (Fmax<30 jum). To check and/or confirm this statement, we can turn to chemical analysis. Although detailed analysis of all craters is impractical, recent work by Graham et al. has been particularly successful at obtaining large datasets of impactor residues from solar arrays, using electron backscatter and x-ray energy dispersive spectrometry techniques [60-62].

Prediction from LDEF data-model it

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