Page:SATCON2 Algorithms Report.pdf/6

The effects of streaks on optical imaging data were discussed in the SATCON1 Report (Walker et al., 2020). In this working group we also discussed the effects on other kinds of data, especially spectroscopy. Low-spectral-resolution fiber spectroscopy is especially vulnerable — the effect of a satellite streak is to add a solar spectrum to the target spectrum, and in the absence of any spatial information it may be hard to spot that your data has been affected. The limiting magnitude of low to medium resolution spectrographs are typically in the 20-25 range, comparable to the effective magnitudes of many satellites. ESO is planning a system with 3000 fibers at low resolution, and they estimate that the satellite contamination (when it occurs) will be up to 5-10 sigma above noise. This could be bad; 1000 sigma is easy to spot, 0.1 sigma can be ignored, but the intermediate range is difficult to notice and yet affects the scientific result. Higher resolution spectrographs have much shallower limiting magnitudes (15-20, even on large telescopes), and will therefore be essentially immune to the contamination by all but the brightest satellites. Finally, although exoplanet transit spectroscopy already has the problem of subtraction at the limits of S/N, its high spectral resolution will prevent significant contamination problems.