NASA has begun its GLOBE Observer citizen science program, using an app to include residents in their research. The GLOBE Observer app, introduced in 2016, includes a new “Land Cover: Adopt a Pixel” module that enables citizen scientists to use their smartphones to photograph the landscape, identify the kinds of land cover they see, and then match their observations to satellite data. Users can also share their knowledge of the land and how it has changed to fill in details of the landscape that are too small for global land-mapping satellites to see. “Even though land cover is familiar to everyone on the planet, the most detailed satellite-based maps of global land cover are still on the order of hundreds of meters per pixel,” said Peder Nelson, a land cover scientist at Oregon State University. “That means that a park in a city may be too small to show up on the global map.” The free GLOBE Observer app is available from Google Play or the App Store. Once users download the app, register, and open the Land Cover module, an interactive tutorial will teach them how to make land cover observations. “Citizen scientists will be contributing photographs focused on a 50-m area in each direction, adding observations of an area up to about the size of a soccer field,” said Holli Kohl, coordinator for the project. “This information is important because land cover is critical to many different processes on Earth and contributes to a community’s vulnerability to disasters like fire, floods, or landslides.” GLOBE Observer is part of the Global Learning and Observations to Benefit the Environment (GLOBE) program, an international science and education program that provides students and the public worldwide with the opportunity to participate in data collection and the scientific process and contribute meaningfully to our understanding of the Earth system and global environment.