A.S. gratefully acknowledges support by a National Science Foundation Graduate Research Fellowship (DGE-1745303). D.F. acknowledges support by NSF grant AST-1614941, "Exploring the Galaxy: 3-Dimensional Structure and Stellar Streams." We acknowledge Cammarata et al., whose figure pushed us to improve Figure 3, and found this up-to-date literature list highly helpful. We thank Taco Cohen, Erwan Allys, Josh Speagle, Catherine Zucker, Core Francisco Park, and Nayantara Mudur for helpful discussions. A.S. acknowledges Sophia S\'{a}nchez-Maes for helpful discussion and much support. Computations in this paper were run on the FASRC Cannon cluster supported by the FAS Division of Science Research Computing Group at Harvard University.

Data products and code associated with the paper "Equivariant Wavelets: Fast Rotation and Translation Invariant Wavelet Scattering Transforms" are made publicly available. This includes a snapshot of a wavelet scattering code and wavelet filter bank developed as part of this work, selected wavelet scattering coefficients used within the text, and code to reproduce the analysis and figures.