We first distinguish between two sets of collaboration members:
Contributing members: Members that have lead a project and/or have made specific concrete contributions to a project/paper. They should be added to papers according to their contributions.
Core members: Caterpillar Core members who initiated the Caterpillar project. They should be invited to join papers in [alphabetical/predetermined/TBD] order.
For any project by Contributors or Core members using particle data, given their past contributions to producing the Caterpillar data set, all Core members should automatically be offered co-authorship.
Core members must actively accept being a co-author by communicating with the paper’s first author, and by providing some contribution to the paper via initial ideas and/or contributions to the project, comments on the draft, suggestions for improvement to text/figures etc, or others, within that time frame.\Once you're strong enough, save the world: