How is science discussed on Bluesky?

Amid the migration of academics from X, the social media platform Bluesky has emerged as a potential alternative. To assess its viability and relevance for science communication, this study presents the first large-scale analysis of scholarly article dissemination on Bluesky, exploring its potential as a new source of social media metrics. We collected and analysed over 2.6 million Bluesky posts referencing 532,302 scholarly articles from January 2023 to July 2025, integrating metadata from the OpenAlex database. Temporal trends, disciplinary coverage, language use, textual characteristics, and user engagement were examined. A sharp increase in scholarly activity on Bluesky was observed from November 2024 to January 2025, coinciding with broader academic shifts away from X. As on X, Bluesky posts primarily concern the health, social, and environmental sciences and are predominantly written in English. Nevertheless, Bluesky posts demonstrate substantially higher levels of interaction (likes, reposts, replies, and quotes) and greater textual originality than previously reported for X, suggesting both stronger interactive and more interpretive engagement. These findings highlight Bluesky's emerging role as a credible platform for science communication and a promising source for altmetrics. The platform may facilitate not only early visibility of research outputs but also more meaningful scholarly dialogue in the evolving social media landscape.