Studies of emergent online science communication genres continuously seek to understand novel forms of popularizations aimed at facilitating expert-with-public engagement. To understand how scientists can successfully engage with audiences in dynamic online environments, we examine Reddit’s science subreddit, attending to the acclaimed Ask-Me-Anything (AMA) series, and subsequent Science Discussion Series (SDS). A move analysis on a corpus of AMA and SDS original posts reveal moves used when engaging audiences through these installments.

This article examines Reddit-users’ (“redditors”) responses to a story concerning proposed legislation that would require parents considering not vaccinating their children to participate in a public-health delivered education session on the science of immunization. In theorizing Reddit as a “peripheral public” venue and attending to its use of algorithms to sort content and commentary, this case study uses a mixed qualitative and quantitative approach to explore the rhetorical strategies employed by redditors as they discuss the proposed legislation and the scientific controversy behind it—suggesting new strategies for investigating participatory media, as well as insights for key stakeholders in the vaccine controversy.

Case studies have been a central methodology employed by scholars working in the rhetoric of science and technical communication. However, concerns have been raised about how cases are constructed and collected, and what they convey. The authors reflect on how rhetoricians of science and technical communication researchers can – and do – construct a variety of case-based mixed-methods studies in ways that may make our research more portable and durable without undercutting the important and central role of case-based analysis.