REVIEW 4 major objections 4 minor 7 references
Are there stars in Bluesky after the return of Donald Trump to the White House?
T0 review · 4 major / 4 minor · reviewed 2026-08-07 · deepseek-v4-flash
Pith's one-line read The paper finds that after the November 2024 US presidential election, Bluesky's share of unique users mentioning scientific papers rose sharply and exceeded X's in two Library and Information Science journals.
desk verdict Timely empirical snapshot of Bluesky's post-election rise in altmetrics, but the 'surpasses X' claim rests on very small samples and needs robustness work. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
The analysis rests on comparing counts of unique social-media accounts that mention a paper, drawn from two retrieval paths. The first path is a custom script that resolves each publication's DOI, collects alternative URLs from an open bibliographic index, and queries the Bluesky API directly; the second uses a commercial altmetric service's API to obtain unique-user counts for both X and Bluesky. The temporal split at November 2024 is the key comparison device, contrasting the full period, in which X dominates, with the post-election months, in which Bluesky's share grows sharply. The journal selection acts as a second control, separating broad multidisciplinary titles from field-specific library and information science journals.
What would settle it
Recompute the post-election platform shares for JASIST and QSS after removing the five most-mentioned papers in each journal; if Bluesky's share no longer exceeds X's, the headline reversal is an artifact of small counts. Extending the same analysis through a later six-month window would also show whether the reversal persists or was a short-lived spike.
Extended reading notes
Core claim
The paper's central claim is that, measured by the number of unique accounts mentioning a publication, scholarly conversation is no longer concentrated on X. Over the whole period X still dominates, holding more than 80 percent of mentions in multidisciplinary journals and more in most library and information science journals, but from November 2024 through March 2025 the distribution becomes much more even. In JASIST, 65 percent of unique user mentions go to Bluesky, and in Quantitative Science Studies the figure is 56 percent, so Bluesky surpasses X in both. The authors connect the timing to political events and to the resulting wave of user migration, but they stress that the durability of the shift is still unknown.
Load-bearing premise
The post-election comparison treats small and uneven journal samples—QSS has only 86 papers in the full period and fewer in the short window—as if the resulting percentages were stable, although a few highly mentioned papers could drive the apparent Bluesky lead.
Editorial extensions
If this is right
- Altmetric indicators that count only X will miss a growing share of the online discussion of papers, making X-only scores increasingly incomplete after 2024.
- Field and country of the journal shape platform adoption, so discipline-level normalization is needed before comparing mentions across fields.
- For large multidisciplinary journals, Bluesky's coverage can approach X's, meaning the platform is no longer a niche source for high-visibility research.
- Future altmetric research should treat X and Bluesky as complementary channels with distinct user communities rather than as substitutes.
Reading between the lines
- The same data could test whether the post-election surge is driven by a small set of politically salient papers; if so, the aggregate reversal might not generalize across all of science.
- The large gap between the two Bluesky counting methods implies that 'a Bluesky mention' is not yet a standardized unit, so comparisons between future studies will be fragile until a shared definition is adopted.
- If Bluesky and X host different communities, combining their mention counts into a single indicator would mix signals; a natural extension is to compare the topics and author types active on each platform.
- If the shift persists, evaluation exercises that rely on past X-based altmetrics would be biased toward disciplines and countries with slower Bluesky adoption.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. This brief communication examines whether researchers are shifting from X (Twitter) to Bluesky after the November 2024 US presidential election. The authors analyze 14,497 publications from three multidisciplinary journals (Nature, Science, PNAS) and four Library and Information Science journals (JASIST, Journal of Informetrics, Scientometrics, QSS) over January 2024–March 2025. They use two complementary data sources: a custom ad-hoc Bluesky API search and Altmetric's user counts for both X and Bluesky. The paper reports that Bluesky is a minority platform over the whole period, but that its share of unique-user mentions rises sharply after November 2024, surpassing X in JASIST (65%) and QSS (56%). The authors interpret this as evidence that the altmetric hegemony of X may have come to an end.
Significance. If robust, the findings would be valuable for the altmetrics and scholarly communication communities: they provide an early, transparently documented observation of a platform shift, with open code and explicit coverage rates. The paper also usefully highlights discrepancies between data sources (ad-hoc vs. Altmetric) that will matter to anyone building on altmetric indicators. However, the central comparative claim—Bluesky surpassing X in specific journals after the election—rests on small and potentially skewed subsamples, and the paper does not provide the statistical or robustness evidence needed to support that claim as stated. The paper is a useful exploratory descriptive study, but its headline conclusion needs stronger support before it can be accepted as a definitive finding.
major comments (4)
- [§3, Figure 2] The claim that Bluesky surpasses X in JASIST (65%) and QSS (56%) in the post-election period is based on very small subsamples. QSS has only 86 papers in the entire 15-month window, so the November 2024–March 2025 subset likely contains only a couple of dozen papers; JASIST has 169 papers total. User-mention distributions are highly right-skewed, so a handful of high-discussion papers could dominate the aggregate shares. The paper reports only aggregate percentages, with no per-paper distribution, confidence intervals, significance tests, or robustness checks. Please report the underlying counts (number of papers and mentions) for each bar in Figure 2, and add a sensitivity analysis that excludes or down-weights outlier papers, or provide bootstrap confidence intervals for the reported shares.
- [Table 1] For QSS, the two Bluesky sources disagree dramatically: the ad-hoc method reports an average of 0.60 accounts per paper, while Altmetric reports 12.44—a factor of roughly 20. Since the post-election reversal in Figure 2 is based on Altmetric user counts, the choice of data source is load-bearing for the paper's central claim. The manuscript does not adequately explain this discrepancy or examine which source is more reliable for the LIS journals. Please add a discussion of the source discrepancy and show how Figure 2 changes if the ad-hoc Bluesky counts are used instead of Altmetric counts.
- [§2, Methodology] The ad-hoc method counts total mentions from the Bluesky API, while Altmetric provides counts of unique users. Table 1 reports 'Avg. Accounts' for both sources without clearly distinguishing total mentions (S1) from unique users (S2). Because the X comparison is based on unique users, the ad-hoc column is not directly comparable, and the juxtaposition may mislead readers about coverage and engagement. Please clarify the metric for each column and, where possible, use the same metric for all comparisons.
- [§3, Figure 1] The text states that Nature mentions rose 'from 440 per week to 1,412 per week by mid-November,' but Figure 1's y-axis and aggregation are not clearly labeled (mentions per week? per month? raw counts?). Please specify the unit and aggregation window in the figure caption, and state whether the quoted numbers are weekly averages or raw weekly counts.
minor comments (4)
- [Abstract] The abstract says the findings mark 'a significant change' and the discussion says the 'evidence ... is clear,' but no statistical significance tests are reported anywhere in the paper. Please qualify these statements as descriptive or add appropriate tests.
- [Footnote 1] Footnote 1 notes that Altmetric only captures posts with a direct link to the publication, which may underrepresent Bluesky or X activity. This limitation is load-bearing for the comparison and should be discussed in the main text or limitations, not only in a footnote.
- [§4, Discussion] The discussion speculates about why Altmetric started tracking Bluesky (e.g., 'increasing opacity of X'). This speculation is not supported by data in the paper and could be labeled as conjecture or removed.
- [References] The reference list is missing a citation for the GitHub repository mentioned in §2; please add the repository URL as a footnote or reference.
Circularity Check
No circularity: the paper's claims are direct observational comparisons of X and Bluesky mention data, with no fitted parameters or derivation chains that reduce to their inputs.
full rationale
The paper is an empirical, descriptive altmetrics study. Its central claim—that Bluesky user engagement rose after November 2024 and in some journals approached or exceeded X—is a direct reading of counts retrieved from the Bluesky API and the Altmetric API. No model is fitted, no quantity is defined in terms of another claimed prediction, and no uniqueness theorem or prior theoretical result is invoked to force the conclusions. The only self-citations (Arroyo-Machado et al., 2021; Robinson-Garcia et al., 2017) appear in the Discussion as contextual references about social-media communities and the meaning of altmetric mentions; they are not load-bearing for the empirical finding. The skeptical concern about small subsamples (e.g., QSS with 86 papers total, so the November 2024–March 2025 window is small) and about right-skewed mention distributions is a legitimate statistical-robustness objection, but it is not a circularity objection: the reported percentages are still observations of external data, not outputs forced by the paper's own assumptions or definitions. Therefore the appropriate circularity score is 0.
Assumptions & free parameters
assumptions (3)
- domain assumption The selected journals (three multidisciplinary, four LIS) are representative of the broader scientific communication landscape.
- domain assumption API-based mention counts (Altmetric and custom Bluesky query) reflect actual social media engagement with publications.
- domain assumption The post-November 2024 period is sufficient to observe a stable shift in platform use.
Cite this review
Pith. "Pith review of Are there stars in Bluesky after the return of Donald Trump to the White House?." pith.science (2026). https://pith.science/paper/WVMS33IV
@misc{pith2026250522702,
author = {Pith},
title = {Pith review of: Are there stars in Bluesky after the return of Donald Trump to the White House?},
year = {2026},
howpublished = {\url{https://pith.science/paper/WVMS33IV}},
note = {Machine review of arXiv:2505.22702}
}
read the original abstract
This study examines the shift in the scientific community from X (formerly Twitter) to Bluesky, its impact on scientific communication, and consequently on social metrics (altmetrics). We analysed 14,497 publications from multidisciplinary and Library and Information Science (LIS) journals between January 2024 and March 2025. The results reveal a notable increase in Bluesky activity for multidisciplinary journals in November 2024, likely influenced by political and platform changes, with mentions multiplying for journals like Nature and Science. In LIS, the adoption of Bluesky is different and shows marked variation between European and United States journals. Although Bluesky remains a minority platform compared to X over the whole period, when focusing on user engagement after the United States elections, we see a much more even distribution between the two platforms. In two LIS journals, Bluesky even surpasses X, while in most others, the difference in user engagement was no longer as pronounced, marking a significant change from previous patterns in altmetrics.
Reference graph
Works this paper leans on
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[1]
Altmetric(@altmetric.com). (2024). Bluesky Social. https://bsky.app/profile/altmetric.com/post/3lcfsenzf552i
work page 2024
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[2]
Arroyo-Machado, W., Torres-Salinas, D., & Robinson-Garcia, N. (2021). Identifying and characterizing social media communities: A socio-semantic network approach to altmetrics. Scientometrics, 126(11), 9267–9289. https://doi.org/10.1007/s11192-021- 04167-8
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[3]
Chan, W. (2022, November 2). Mastodon gained 70,000 users after Musk’s Twitter takeover. I joined them. The Guardian. https://www.theguardian.com/media/2022/nov/01/mastodon-twitter-elon-musk- takeover
work page 2022
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[4]
Holtermann, C. (2024). With Surge in New Users, Bluesky Emerges as X Alternative. The New York Times. https://www.nytimes.com/2024/11/12/style/bluesky-users- election.html
work page 2024
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[5]
Hou, A. C. Y., & Shiau, W.-L. (2019). Understanding Facebook to Instagram migration: A push-pull migration model perspective. Information Technology & People, 33(1), 272–295. https://doi.org/10.1108/ITP-06-2017-0198
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[6]
User Migration across Multiple Social Media Platforms
Jeong, U., Nirmal, A., Jha, K., Tang, S. X., Bernard, H. R., & Liu, H. (2023). User Migration across Multiple Social Media Platforms (Version 2). arXiv. https://doi.org/10.48550/ARXIV.2309.12613
work page Pith review arXiv doi:10.48550/arxiv.2309.12613 2023
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[7]
Robinson-Garcia, N., Costas, R., Isett, K., Melkers, J., & Hicks, D. (2017). The unbearable emptiness of tweeting—About journal articles. PLOS ONE, 12(8), e0183551. https://doi.org/10.1371/journal.pone.0183551
Reviewed August 7, 2026 · model on record in the stance chip above.
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