<p><strong>Background</strong></p><p>Wikipedia is an open source, web-based encyclopedia, allowing anonymous and registered users to create, edit and improve articles. A survey in 2018 showed that as many as 90% of Wikipedia's editors were male and as many as 81% of contributors were from the Global North [1]. &#160;</p><p>In addition, there are fewer contributions about women, especially in STEM fields, and they are usually less developed [2]. In October 2014, only 15.53% of English Wikipedia's biographies were about women [3]. The WikiProject <strong>Women in Red</strong> was founded in July 2015 with the objective to address this gender bias in Wikipedia content. They succeeded in increasing the above-mentioned percentage to <strong>18.71%</strong> as of 11 January 2021 [2].</p><p>Today, Wikipedia is within the 20 most popular websites [4] and every month it attracts more than 1 billion unique visitors [5]. Wikipedia therefore has a huge potential to change publics perception of who is doing science and what a scientist &#8216;looks&#8217; like.</p><p><strong>(Women) planetary scientists on Wikipedia?</strong></p><p>In June 2020, there were only 189 planetary scientist biographies on the English Wikipedia, including 48 biographies of female planetary scientists (25%). This percentage is in agreement with the percentage of women in the International Astronomical Union from all ESA&#8217;s Member States (24%) [6], but planetary scientists are clearly underrepresented on Wikipedia. Many of them either do not have a Wikipedia biography yet, or if they do, they are often misclassified under the category of &#8220;astronomers&#8221; or &#8220;astrophysicists&#8221;.</p><p><strong>A Planetary Sciences</strong><strong> Edit-a-thon</strong>&#160;&#160;&#160;&#160;</p><p>The Diversity Committee of the Europlanet Society aims to highlight diversity within the planetary science community. Therefore, they organised, in collaboration with Women in Red and WikiDonne, the first <strong>Planetary Science Wiki Edit-a-thon</strong> during the Europlanet Science Congress (EPSC) 2020 [7]. An Edit-a-thon (&#8216;edit marathon&#8217;) is an organized event where editors from an online community (such as Wikipedia in this case) write, translate and improve articles on a specific topic [2]. Thirty persons received a basic editing training, resulting in 1 new article and 5 translated ones. A small subgroup still meets every month to continue the project.</p><p><strong>References</strong></p><p>[1] https://meta.wikimedia.org/wiki/Community_Insights/2018_Report</p><p>[2] https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Women_in_Red &#160;</p><p>[3] Eduardo Graells-Garrido, Mounia Lalmas, Filippo Menczer, "First Women, Second Sex: Gender Bias in Wikipedia", arXiv, 9 February 2015, p. 3.</p><p>[4] "Wikipedia.org Traffic, Demographics and Competitors".&#160;www.alexa.com. Retrieved&#160;October 1,&#160;2019.</p><p>[5] https://stats.wikimedia.org/#/all-wikipedia-projects</p><p>[6] Piccialli A., et al., Participation of women scientists in ESA Solar System missions: a historical trend, Adv. Geosci., 53, 169&#8211;182, https://doi.org/10.5194/adgeo-53-169-2020, 2020.</p><p>[7] https://www.europlanet-society.org/epsc-2020-planetary-science-wiki-edit-a-thon/&#160;&#160;&#160;&#160;</p>