Our reading of the data as of October 13, 2026. The charts update every day; these notes are reviewed monthly.
Instrumentation papers are growing fastest of all
Instrumentation and methods (astro-ph.IM) is the fastest-growing part of astro-ph: 3,342 listings in January-September 2026 against 2,524 in the same months of 2025, up 32.4%, while the other five categories grew 8.5% to 14.8%. The jump is concentrated from June 2026, when monthly volume went from 285 (May) to 465 and stayed between 448 and 476; we have not analyzed whether that is a lasting step or a temporary surge. Over the decade, the category more than doubled (1,615 in 2015, 3,576 in 2025).
+32.4% year on year (Jan-Sep); +121% from 2015 to 2025.
arxiv.org
Exoplanets lead the science fields in growth
Among the science categories, Earth and planetary astrophysics, which includes exoplanets (astro-ph.EP), is growing fastest: up 14.8% year on year (2,631 listings in January-September 2026) and up 90% over the decade. September 2026 was its busiest month in the last year, with 374 papers. Inside abstracts, "exoplanet atmosphere" rose from 54 to 75 mentions (+39%), "biosignature" from 37 to 46 (+24%) and "sub-Neptune" from 71 to 84 (+18%), small counts that point the same way.
astro-ph.EP +14.8% (Jan-Sep 2026 vs 2025); +90% from 2015 (1,627) to 2025 (3,096).
arxiv.org
Square Kilometre Array mentions doubled in six months
"Square Kilometre Array" appeared in 97 astro-ph abstracts from April to September 2026, up from 49 in the previous six months: the fastest rise of the 40 terms we track. The telescope is not yet doing science, so this reads as preparation: SKA-Low science verification is planned to begin in 2027, and France joined as the 14th member state in June 2026. Related radio-cosmology terms also rose, "cosmic dawn" by 53% (45 to 69) and "21-cm" by 21% (110 to 133).
49 to 97 abstracts (+98%).
skao.intskao.int
Little red dots and cosmic dawn draw attention
JWST's early universe is pulling researchers in. "Little red dots," the compact red objects Webb finds in the early universe, rose from 86 to 131 abstract mentions (+52%), and "JWST" itself from 769 to 939 (+22%), making Webb the most-mentioned facility among our terms. Demand for the telescope matches: Cycle 5 drew a record 2,930 proposals asking for 99,782 hours, about 12 times the time available, from 7,363 investigators at 849 institutions.
"little red dots" +52%; "JWST" +22%; Cycle 5 oversubscription about 12:1.
stsci.edu
Dark energy attention concentrates on DESI's data
Mentions of "DESI" rose from 416 to 468 abstracts (+12.5%), while the generic phrase "dark energy" slipped from 505 to 487 (-4%) and "Hubble tension" from 86 to 82. The field is working through one data set: DESI finished its planned five-year map in April 2026 with more than 47 million galaxies and quasars (goal: 34 million), and its full-survey dark energy results are due in 2027. The current hint of evolving dark energy is 2.8 to 4.2 sigma depending on the supernova sample, short of the 5-sigma discovery threshold.
"DESI" +12.5%; "dark energy" -4%; 47 million+ objects mapped.
news.ucsc.eduarxiv.org
Neutrinos, radio bursts and magnetars gain ground
Multi-messenger and transient astronomy is rising together. "Neutrino" grew from 459 to 528 abstracts (+15%), "fast radio burst" from 118 to 160 (+36%), "magnetar" from 113 to 138 (+22%) and "kilonova" from 56 to 66 (+18%); "gravitational wave" remains the most-mentioned of all 40 terms at 1,065. Two milestones landed in 2026: the Nobel Prize in Physics went to Francis Halzen for IceCube and high-energy astrophysical neutrinos, and the gravitational-wave catalog reached 390 confirmed events in May 2026.
"fast radio burst" +36%; "neutrino" +15%; "gravitational wave" 1,065 mentions (+6%).
nobelprize.orgobserving.docs.ligo.org
US science budgets wobble while Europe spends more
The money is moving in opposite directions. Congress rejected the proposed FY2026 cuts and enacted $1.595 billion for NASA astrophysics (the request was $523 million), but the FY2027 request again proposes cutting NASA's Science Mission Directorate by 47%, from $7.25 billion to $3.9 billion. In November 2025, ESA member states committed a record EUR 22.07 billion for three years, 32% more than in 2022 (17% after inflation).
NASA astrophysics FY2026 enacted $1.595B vs $523M requested; FY2027 request -47% for science; ESA +32%.
everycrsreport.comspace.comspacepolicyonline.com