Dear Richard, I wrote s small shiny app to improve the search for CRAN-packages. It can be installed from GitHub: https://github.com/discoleo/PackageBrowser Searching for "(?<![- ]cat)astro|sun" yields 19 packages. A few (2 or 3) are unrelated. The remaining may be interesting, e.g. suntools, suncalc, astroFns. Sincerely, Leonard [[alternative HTML version deleted]]