Page:SATCON2 Community Engagement Report.pdf/11



Members of the astrophotography community were on the front line when the subject of satellite megaconstellations first entered the global public consciousness after the initial SpaceX Starlink launch in May 2019. Before the first group of 60 Starlink objects was raised to its final, 550-km station and the satellites were still flying in close proximity, their tendency to leave multiple parallel streaks in astrophotos (e.g. Fig. 1) was exploited by world media to suggest that Starlink represented a serious or even existential threat to ground-based astronomy. Later it was revealed that not even space-based astrophotography was immune to the threat, as it was found that the Hubble Space Telescope, orbiting below on-station Starlink objects, experienced the same satellite trails in its images.

In SATCON1, we explored the potential for large satellite constellations to yield negative impacts on astronomical images ranging from wide-field “nightscapes” to deep imaging through telescopes to casual astrophotography employing the cameras built into mobile devices. Using the best information available at the time in terms of the expected number and brightness of objects planned for launch in the 2020s, we rated their impacts to various modes of astrophotography from “negligible” to “fatal”. In the latter case, the expected victim was nightscape photography, which we expected to “suffer the same problem as high-AΩ telescopes, albeit with considerably smaller apertures.” Assuming the fully built SpaceX Starlink and OneWeb constellations, simulations suggested an average of two satellite trails per square degree would appear in every 60-second exposure taken near the horizon. From this we concluded that “we do not see how wide-field astrophotography can be performed to current standards with the projected density and brightness of the steady-state configurations of the Starlink2 and OneWeb constellations.”

For SATCON2, we contacted both amateur and professional astrophotographers to obtain information on their attitudes toward large satellite constellations. We took a cue from the online-survey approach of the Community Engagement Working Group’s subgroup aimed at soliciting opinions from the amateur astronomy community. However, our survey was marketed differently from the survey to broadly defined "amateur astronomers". While there certainly is some overlap between the groups, the astrophotography survey was aimed mainly at individuals who are less likely to identify as amateur astronomers and more as landscape photographers for whom the night sky is another backdrop. Consequently there were more responses from "nightscape" photographers than from those who engaged in planetary or deep-sky astrophotography, usually with the aid of telescopes. Rh