Public science refers to a science outreach project that has been conducted outdoors or in another type of public or accessible space such as a public park, metro stop, library, university campus, etc. Similar to public art, there are typically aspects of collaboration, community support and involvement, and even site specificity involved in public science efforts. Public science initiatives attempt to reach new audiences (particularly, non-experts who might not actively seek out science) by hosting events in alternative informal learning environments. By definition, these public science projects are outside the walls of the science center or science museum, where the main focus of that particular space is not typically science outreach.
"Science City" is an example of a public science initiative that ran from June 1994 through May 1995. Created by staff and consultants from the New York Hall of Science, "Science City" was an outdoor exhibition that utilized the street, fences, buildings and other public structures in New York City to attract the "non-museum-going" public to the science in everyday life. The exhibition asked questions such as "Why is it warmer in the city?", "What pulses under the street?" and "What's under the sidewalk?" to help increase public awareness about the science and technology that runs invisibly underneath modern urban life.
The concept spread to Sweden in 1997 with the The International Science Festival in Gothenburg which is an annual festival in central Gothenburg with thought provoking science activities for the public. The festival is visited by about 100 000 people each year. This makes it the largest popular science event in Sweden and one of the largest popular science events in Europe.
Recent examples of public science initiatives in astronomy include “From Earth to the Universe” (FETTU), a project of the International Year of Astronomy 2009 (IYA2009). FETTU displayed large-scale images of astronomical objects in non-traditional and mostly public locations such as parks, airports, art festivals, shopping malls, and others (see figures 1 and 2). By 2011, FETTU had been exhibited at about 1000 sites worldwide, with 50 sites in the United States. One result from FETTU was preliminary data and analysis on non-self-selective audiences for public science exhibitions. A follow-up to FETTU, "From Earth to the Solar System" began in 2011 and is providing further opportunity to analyze the outcomes of bringing content to casual visitors in alternative science outreach venues.
Another current public science initiative in astronomy is Music and Astronomy Under the Stars, a NASA-funded program at public parks before, during or after music performances and at other outdoor family-friendly venues. Also, Voyage to the Solar System, a project from the National Center for Earth and Space Science Education (NCESSE), has installed scaled replicas of the major bodies of the Solar System outdoors in several U.S. cities (including Washington, D.C., and Houston, TX) with others planned (Des Moines, IA, Orlando, FL, and Baltimore, MD, for example). Voyage and other Solar System scale model projects represent a different way to place astronomy outreach in the public sphere.
Covering broader science topics, science festivals such as the USA Science and Engineering Festival, the San Diego Science Festival, the World Science Festival in New York City (see figure 2), and others present science in a public sphere through large outdoor programs with exhibits, discovery stations, talks and additional themed activities.
Other public science efforts include Science on the Buses, in which city buses in many major European Union cities were decorated with large informational science posters in November 2002. Likewise, a project by the group placed “advertisements” with science facts on  buses in Toronto during July 2009.
Science Cafes are another public science effort that initiates a discussion on a science topic in pubs or cafes, usually with a local scientist in attendance to answer questions and present information.
- Arcand, K.K., Watzke, M., “Creating Public Science with the From Earth to the Universe Project” Science Communication. accepted September 2011.
- Watzke, M., Arcand, K.K., “The Universe Brought Down to the Streets: The “From Earth to the Universe” Project”. Mercury magazine. Volume 39 #1. Spring 2010. (excerpt: http://www.astrosociety.org/pubs/mercury/39_02/watzke.html)
- Bell, P., Lewenstein, B., Shouse, A. W., Feder, M. A.(Eds). 2009, Learning science in informal environments: People, places and pursuits. Washington, D.C.: The National Academies Press.
- Norsted, B. A., 2010, “Take Me Out to the Ball Game: Science Outreach to Non-traditional Audiences” Science Education and Outreach: Forging a Path to the Future. ASP Conference Series, Vol. 431, p.170-173.
- Cole, P.R. & Cutting, J.M., 1996, “The Inside Story of Science City - An Outdoor Public Science Exhibition”. Curator: The Museum Journal. Volume 39 #4, p.245-261.
- vartgoteborg.se - Världsrekordförsök inleder Göteborgs tolfte vetenskapsfestival, Vårt Göteborg, 11 april 2008
- goteborg.com - Festivalens hemsida (archivelink 2006-11-01)
- Forskning och framsteg, 3/08 sid 64 (dead link 2012-04-24)
- Russo, P. and Christensen, L.L. (Eds.), 2010 “International Year of Astronomy 2009 Final Report” International Astronomical Union, ISBN 978-3-923524-65-5
- Arcand, K.K., Watzke, M., 2010, “Bringing the Universe to the Street: A Preliminary Look at Informal Learning Implications for a Large-Scale Non-traditional Science Outreach Project”. JCOM Journal of Science Communication. Vol. 09, Issue 02, 1. http://jcom.sissa.it/archive/09/02/Jcom0902%282010%29A01/
- Lubowich, D., 2010, “Music and Astronomy Under the Stars 2009” Science Education and Outreach: Forging a Path to the Future. ASP Conference Series, Vol. 431, p.47-53.