In April 2026, volunteers logged 4,730,752 Acts of Science during Citizen Science Month, a campaign led by SciStarter. The official goal was 2.5 million Acts, a number tied to the 250th anniversary of the United States. Volunteers reached the goal on April 22, Earth Day, and the final total was almost double the target.
What Counts as an Act of Science
An Act of Science is a single contribution to a research project listed on SciStarter. Examples from the 2026 campaign:
- Identifying animals in wildlife camera images
- Classifying cloud formations in Mars imagery
- Transcribing handwritten historical records
- Annotating blood vessels for Alzheimer’s research through an online game
- Submitting cloud, tree and land cover observations through the NASA GLOBE Observer app
Citizen Science Month 2026 in Numbers
SciStarter published these final results on May 1, 2026:
- Acts of Science: 4,730,752
- Volunteers: 450,918
- Countries: 140
- Research projects and events: more than 950
- Events held in April: 481, about one-third of them in the “Connected” format
- Events hosted by libraries: 34%
- Volunteers active in more than one project: 41%
- Social media reach: more than 13 million people
Volunteers who logged at least one Act between April 1 and April 30 received a free 12-month New Scientist digital subscription.
Growth Over Three Years
The April challenge has grown every year:
- 2024: 1.129 million Acts, with the 1 million mark reached on April 24. About 500,000 volunteers from 126 countries took part.
- 2025: 3,026,611 Acts from more than 500,000 participants across over 1,000 projects and events.
- 2026: 4,730,752 Acts from 450,918 volunteers in 140 countries.
From 2024 to 2026, the total number of Acts grew more than fourfold, while the number of volunteers stayed between 450,000 and 500,000. Each volunteer contributed about 2 Acts on average in 2024 and more than 10 in 2026.
Five Connected Event Days
The 2026 campaign introduced “Connected” events. These were single-day efforts in which libraries, schools and individuals worked on the same project at the same time.
- April 2, Cloudspotting on Mars: more than 11,000 classifications in one day, over 10 times the project’s typical daily average. The project also passed 20,000 registered participants.
- April 10, Voices of Freedom: volunteers transcribed more than 200 pages of post-Civil War records with the Smithsonian Transcription Center and the National Museum of African American History and Culture, for a total of 4,872 Acts.
- April 16, Stall Catchers: volunteers annotated more than 16,500 blood vessels, saving an estimated 42 hours of laboratory work.
- April 22, Snapshot Wisconsin: volunteers classified more than 28,900 trail camera images, about three times the project’s usual pace.
- April 29, Rubin Comet Catchers: volunteers classified 44,000 images in a search for active comets, double the usual daily effort.
The NASA GLOBE Contribution
NASA’s GLOBE Program added almost 15,000 Acts during April 2026:
- Cloud observations: 10,391
- Tree observations: 972
- Land cover observations: 497
- Mosquito habitat observations: 69
- Data Entry observations: 1,297
- New GLOBE Observer accounts: 1,748
More than 1,500 unique users submitted GLOBE data during the month.
Organizers and Partners
SciStarter and Arizona State University coordinate Citizen Science Month. Support comes from the National Library of Medicine at the National Institutes of Health, under a cooperative agreement with the University of Iowa and the University of Pittsburgh.
Named 2026 partners and supporters include:
- America250, as official partner
- NASA and the Jet Propulsion Laboratory
- The Smithsonian Institution
- Zooniverse
- Cornell University
- The Association for Advancing Participatory Sciences
- The Gordon and Betty Moore Foundation
- New Scientist and Idealist.org
More than 1,000 public libraries take part through the Citizen and Community Science Library Network. SciStarter Ambassadors and NASA Solar System Ambassadors served as event moderators, guides and panelists.
Measured Outcomes for Participants
The ASU College Research and Evaluation Services Team evaluated the 2024 campaign. Its results:
- 94% of surveyed participants rated the activities “excellent” or “good.”
- 91% reported more confidence in collecting or analyzing data.
The Web Infrastructure Behind Volunteer Research
The campaign’s main platforms use the .org top-level domain, including scistarter.org, citizensciencemonth.org and zooniverse.org. Nonprofits, research initiatives and community projects commonly use the .org extension. New citizen science groups can buy .org domain names to host project pages, recruit volunteers and publish results.
Environmental projects make up a large share of citizen science work, and the same data-driven tools now shape green business. An analysis of the complicated relationship between green entrepreneurs and generative AI covers the trade-off between efficiency gains and data center electricity use.
How to Take Part
- Platform: SciStarter lists more than 3,000 research projects, events and tools.
- Time commitment: many projects accept contributions that take a few minutes, such as classifying a single image.
- Location: online projects accept volunteers from any country. Field projects use mobile apps such as GLOBE Observer.
- Next campaign: Citizen Science Month takes place every April.
