Today, March 16, marks the annual International Day of Light, with close to 70 countries hosting events to draw attention to the special role light plays in the sciences, education, communications, energy, and culture around the world. Sponsored by UNESCO, the United Nations Educational Scientific and Cultural Organization, this year’s celebration puts special emphasis on stimulating young people and women — especially in developing countries — to study science and engineering (https://www.photonics.com/Articles/International_Day_of_Light_2019_Focuses_on_Youth/a64700). The impact of light pollution is another prominent theme (https://www.photonics.com/Articles/International_Day_of_Light_Brings_Light_Pollution/a64707). Worldwide, the number of participating countries increased from 54 to 70 in just one week with about 400 events taking place throughout the day. From Bangladesh to Iceland, events and presentations focused on themes such as “Inspiring Education in Optics and Photonics” in Indonesia; “If Light Disappears?” in Algeria; “Light in Academic Training” in Ivory Coast; and “The Dark Side of Light” in New Zealand. Bethany Downer, IDL secretariat, said the second edition of celebration has been a tremendous success with the number of collaborating countries increasing on the day of the events. “Over 400 events have already taken place in 70 countries worldwide, bringing together an international community of scientists, students, and the public,” she said. “A special focus of celebrations took place at the Illuminating Education conference held at the UNESCO institute in Trieste. Presentations covered a wide range of topics from leading-edge inspiring science to discussions of science education, issues of diversity and gender equality, and practical career advice.” ‘Optica Fantastica’ Trieste, Italy, is “ground zero” of sorts for today’s celebration. The city hosts the Illuminating Education conference at the UNESCO International Centre for Theoretical Physics (ICTP), with presentations from Roberta Ramponi, president of the International Commission for Optics, and Michael Berry, of the University of Bristol and an ICTP distinguished lecturer. Berry’s talk, “Optica Fantastica,” is structured around a series of images to illuminate the physics of light, a topic ideally suited to engage interest and promote science outreach to the public of all ages. The “Lighting and the Future” series, also at ICTP today, addresses diverse challenges for science and education. Themes include sustainable development, the need for improved awareness of lighting quality, and education and sustainability initiatives in the public and private sector. Presenters include Sandro Scandolo from ICTP; Krisinda Plenkovich, SPIE; Brian Liebel, Illuminating Engineering Society; John O’Hagan, CIE; David Sampson, University of Surrey; and Prajna Khanna, Signify Foundation. Cather Simpson, of the University of Auckland, presents a keynote talk, “Using Physics to Feed the Planet,” to explain how a greater understanding of light is changing the way we grow food. Documentary Debut John Taylor, of the Optical Society, is presenting “Disappearing in the Darkness,” a preview to a new documentary premiering in 2019 on an art installation in Washington, D.C., that opened on the first International Day of Light last year. In a session on career challenges, Jess Wade, of Imperial College in London, discusses her work on challenging stereotypes and the Institute of Physics’ efforts to improve gender balance in physics classrooms. She also describes her research on next-generation OLEDs. In addition, Amna Abdalla Mohammed Khalid, vice chair of the Next Einstein Forum (NEF) Executive Committee, delivers a presentation on the Aims and Objectives of the NEF community of scientists in creating a unified African scientific identity to enable the scientific transformation of Africa through fostering an environment for innovative scientific discovery. UNESCO Director-General Audrey Azoulay said improved communication networks can lead to more cultural exchanges, more justice, responsibility, and peace. “Particularly crucial are the issues surrounding electrical access to light as a means of improving the standard of living in developing countries, and the issues concerning the optical fiber used to connect the world’s citizens through the internet.” Ending the day are student and society sessions by student representatives from international networks of EPS, IEEE, OSA, SPIE, and IAPS. Presentations will cover broad topics, including science outreach and how students see their careers in the future. Participants include: Ezabo Baron, IEEE PS; Roberta Caruso, EPS; Xiang Dino Dai, OSA; Perla Marlene Viera González, SPIE; Duarte Graça, IAPS; Kithinji Muriungi, IEEE PS; and Artemis Tsimperi, IAPS. OSA student chapter head Xiang “Dino” Dai, a senior from the electro-optical department of Changchun University of Science and Technology, China, presents a “Students and Societies” session. Dai’s chapter established a cooperation agreement with the Changchun, China, Optics Science and Technology Museum that includes developing programming for science outreach.