A first look at Altmetric insights from Bluesky

December 2024  marked a milestone in Altmetric: we have added Bluesky to our list of Social Media platforms, the first addition of its type in many years. The data is available to all users of the Altmetric badge, and subscribers to Explorer, and our API and GBQ products. (See the related news and an interview with Miguel Garcia, Product Director, Altmetric for more information)

As any former user of Myspace can tell you, social media use varies over time, and characteristics of a platform will develop following its usebase. In this first blog post dedicated to analysing Bluesky data, the Altmetric Data Insights team is going to give you some early highlights.

About Bluesky

Bluesky is what used to be called a micro-blogging site: users can write short messages to share with their networks, they can use links and hashtags, and can interact with other users’ messages – liking, reposting and quoting are typical activities. At Altmetric, we have access to much of this data, and we’ve also cross-referenced the posts against our Dimensions data, so we can look at Open Access status, academic subject, journal and document type.

Early insights

At the moment of launch, we’d captured approximately 0.3M posts, linked to almost 100k research outputs – a month later we’ve recorded close to 1M individual posts. Perhaps not unsurprisingly, the most shared piece of research is “A Place of Joy”, an article published in Nature about the growth of the research community on Bluesky. The oldest article is a 1684 account of an earthquake near the ancient city of Constantinople, while the most viral papers (those that have the highest ratio of reposts to original posts) are those that discuss issues relating to DEI in academia, and the use of generative AI.

Both Open Access and preprints are performing strongly on Bluesky. arXiv is currently the most popular source of shared research, with the journals Nature, Nature Communications, and New England Journal of Medicine performing strongly, while PNAS, Plosone, Scientific Reports and The BMJ seeing very high levels of activity.

Despite the dominance of medical journals, Bluesky is a remarkably evenly distributed source of attention at the current time, with good coverage from all disciplines.

Bluesky allows users to post original messages, to share them, and also to quote them. This data allows us to calculate a ratio known as “virality”, being the total number of reposts divided by the number of original posts. Currently, this number stands at 1.37, meaning that the average Bluesky original post will have 0.37 reposts.

In reality, this number is skewed (as with all social media networks). On the left, we see this breakdown by unique publication, and on the right, by posts. This tells us that while many publications will only see a small number of original posts, a subset will have a much larger volume of reposts. Virality is a key indicator to understanding the performance of discipline and journals, as well the effect of Digital Opinion Leaders who are becoming an increasingly important vector in scientific communications.

The development of Bluesky as an attention source

This blog post is the first in a series that will focus on this emerging attention source: we’ll be posting more analysis as our data grows. Two areas that will be covered are comparisons with X (still the strongest source of Altmetric attention), and the sentiment of conversations on Bluesky – this is likely to be the subject of our next article.

If you have any questions or suggestions for future analyses, please contact the Altmetric team.