At his general audience, Pope Francis announces that he will publish a follow-up to his landmark 2015 "Laudato Si" (Praised Be) encyclical on October 4, urging everyone to stand by the victims of environmental injustice and work to preserve the environment. The 86-year-old Francis has made the protection of the environment a cornerstone of his pontificate, and has urged urged young people to focus on caring for the planet and fighting climate change. IMAGES AND SOUNDBITES