International Day of Light

16 May

Light plays a central role in our lives. On the most fundamental level, through photosynthesis, light is at the origin of life itself. The study of light has led to promising alternative energy sources, lifesaving medical advances in diagnostics technology and treatments, light-speed internet and many other discoveries that have revolutionized society and shaped our understanding of the universe. These technologies were developed through centuries of fundamental research on the properties of light – starting with Ibn Al-Haytham’s seminal work, Kitab al-Manazir (Book of Optics), published in 1015 and including Einstein’s work at the beginning of the 20th century, which changed the way we think about time and light.

The International Day of Light celebrates the role light plays in science, culture and art, education, and sustainable development, and in fields as diverse as medicine, communications, and energy. The celebration will allow many different sectors of society worldwide to participate in activities that demonstrates how science, technology, art and culture can help achieve the goals of UNESCO – building the foundation for peaceful societies.

The International Day of Light is celebrated on 16 May each year, the anniversary of the first successful operation of the laser in 1960 by physicist and engineer, Theodore Maiman. This day is a call to strengthen scientific cooperation and harness its potential to foster peace and sustainable development.

MESSAGE FROM THE DIRECTOR-GENERAL

"Light is life. Without light, life on our planet would not exist. In studying light through astrophysics, we delve into some of the deepest mysteries of the universe. In exploring optics and quantum optics, we plunge into the heart of matter itself.

It is therefore unsurprising that, across cultures, light is a universal symbol of life, inclusion, and renewal. Light is associated with illumination, or spiritual awakening. Light is seen in opposition to darkness, which represents ignorance and intolerance.

Although light symbolizes knowledge, we are still blind to many of its everyday applications. The high broadband speeds we use today could not have been achieved without fibre optics. DVDs and Blu-Ray discs could not be read without light. Solar energy is a source of heating. Light-based technologies are essential in healthcare, where optical instruments and tools are used for analysis and imaging, and ultraviolet light sources are used for sterilization. These technologies are also essential for sequencing genomes – like that of the SARS-CoV-2 virus, currently wreaking havoc around the world.

It is these exceptional properties that we celebrate every 16 May, on the International Day of Light. This year, as the world grapples with the COVID-19 pandemic, we hope that this event will also be an opportunity to shed light on unprecedented global challenges."

— Shamila Nair-Bedouelle - Assistant Director-General for NaturalSciences, on the occasion of the International Day of Light 2020

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