Light is Life – without light, life will simply perish on Earth.
Technically, light is an Optical phenomenon that we observe through events that result from the interaction of light and matter. With this great influence of light in our lives, the United Nations marks the year 2015 the International Year of Light, with an objective of awareness on a global scale with an initiative to be inspired, educate and to appreciate the principle role of light in science and culture and synchronizing with scientific discipline that can enhance sustainable development, for the development of society towards better living conditions in the future by providing a way out to worldwide challenges in agriculture, communications, education, energy and health.
It was about a thousand year ago that the first studies of optics lay ground to power today’s internet communications. A look back in time, Sir Isaac Newton (17AD) first demonstrated that white light is made of different colors of light on a much wider electromagnetic spectrum of the light wave length that we see in a rainbow. Later in the 20c AD, Albert Einstein explained the Optical phenomenon based on his calculations that light was a wave and atom. At this breakthrough, scientists’ explored infinite ways on how light can be used to brighten up life through multiple sources:
We are all aware of the many forms of light in nature around us. We wake up into sunrise and usually retire the day at sunset. The sun is one of the greatest light energy that can transform light into other uses. The light of the sun is in itself a natural source of vitamin D to our health and vitality. Deficiency of vitamin D poses health risks like low blood level and symptoms of bone pain and weak muscles. The light paints life forms on earth (plants, wildlife and fauna); the color of the seas and oceans and life underwater rely on minute balance of temperature that ensures the growth of fragile ecology. Intense heat can burn the forests and damage coral floors as we see today under a more wider use of term as ‘global warming’, which has also effected weather to extreme conditions of longer winter or summer spells.
Rainbow is a colorful vista of optical phenomena. Soon after the rain when the soft rays of the sun penetrate water droplets, a multi-color arch is formed over the horizon through refraction or bending of light through water droplets. In scientific terms: “refraction is a phenomenon that often occurs when waves travel from a medium with a given refractive index to a medium with another at an oblique angle”.
Sunrise and sunset is another form of refraction of light. In astronomy term, a sunset is “the point when the trailing edge of the sun’s sphere disappears below the horizon”. Soon after the sun disappear from our sight – the sky transforms into nature’s canvas of warm colors tuned into yellow, red, brown with a dash of pink and violet. This formation is due to “scattered airborne particles passing through rays of white sunlight traveling through the atmosphere”.
During the sunset the sky renders strong colors than the sunrise because of the dense particles in the evening air and atmosphere than the scattered particles in the less polluted morning atmosphere.
Also known as the Aurora Borealis, the Northern lights is an amazing natural light display that occurs in the sky in the arctic (northernmost) region on Earth.
Aurora Borealis is formed by electrically charged particles that emanate from the sun.
Although sighting in unpredictable, the best time to see the auroras is in the months of October, November, February and March.
In fact, auroras can be seen all over the world, but occur most frequently in high altitude regions. It was early November that I have had rare sighting of Aurora Borealis in Islamabad over Shah Faisal masjid – unfortunately, at that time, now being aware of this phenomena, I thought of it as an unusual sky after sunset with mainly green in color. Caused by the collision of solar wind and magnetospheric charged particles with the high altitude atmosphere, most auroras occur in a band known as the auroral zone. Many times the auroras are green, as high energy particles strike the Earth’s atmosphere, causing the air to glow as electrons resettle into their oxygen hosts. Other colors are occasionally noticeable as atmospheric nitrogen also becomes affected. In later sequences the Moon and rising stars are also visible. Farther to north cape, Svalbard Island and the Lofotel Islands are the best places in the world to be delighted witness aurora borealis (or the northern lights), named after the Roman goddess of dawn. Nature’s phenomenal dancing light show in the night sky is a sight wonder, which can be also seen in the Arctic, Canada (North), Scotland (Orkney Isles) and the USA (Alaska).
Light in Art and Culture:
Photographers, painters, performers of modern arts rely on the dynamism of light and shade in the creation of an atmosphere setting a mood to the various form of art. Artists from all around the world while using natural or artificial light as the key to their creations though see light with different perspectives. A single creation that entertain and teases the imagination of the eyes of the beholder can sell worth millions of dollars, thus light – bringing prosperity to the artist’s life. With the availability of modern technology and infinite possibilities of using light into creating an art piece to entertain, art and cultural performances has reached new heights.
What started with the invention of the incandescent light by Joseph Swan and Thomas Edison, electricity became the source of artificial light. Today, we see the evolution of artificial light taking into shape from fluorescent lighting to the modern environmental friendly Light Emitting Diode (LED) lights.
Solar Energy: The sun is the biggest source of energy that can be transformed into heat and electricity. Solar energy is produced by harnessing heat from the sun’s rays using technologies like solar heating, solar photovoltaics (solar panels) and solar thermal electricity, amongst others. Today, consumers are looking at the clean solar energy technology and the possibilities of installation in urban homes and commercial premises, also in agriculture, horticulture, transportation sectors, desalination and water recycling, solar thermal and in rural areas. The use of Solar energy installation today remains costly as of lack of demand due to unawareness, particularly in the under developing countries. Once the use of solar energy popularize, this form of energy will provide a practically-inexhaustible resource to enhance sustainability, reduce pollution thus making a positive contribution towards a remedy to slow process of global warming. In a country like Pakistan where people are subjected to misery of long duration of load shedding, solar energy is the immediate solution to better living condition and rid conventional use of electricity.
Laser: From scanning price of your grocery consumption purchases and health check to a collection of favorite entertainment choice on a DVD, light laser technology is commonly in use today in service sector, medical, CD technology. and Free Electron Laser (FEL’s) used in fundamental and applied research in scientific researches. Known as synchrotrons and FEL’s, a particle accelerator is placed at the core of large FEL’s machine, which is used in generating high intensity bright light. The intensity of the light is so powerful that it can clearly show the atomic and molecular detail of the world around us. There are now more than 60 synchrotrons and FELs around the world dedicated to applications to name a few: physics, engineering, pharmacology, and new materials.
Photosynthesis: The process “when energy from light is absorbed by proteins called Reaction Centers that contain green chlorophyll pigments”. However, as it appears simple, photosynthesis is a complex process. Although it is performed differently by different species, the process converts energy in sunlight to chemical energy used by green plants and other organisms is called photosynthesis. The basis that grow food for global population, it also produces significant bio product – one being fossil fuel.
Photonics: the science and technology of “generating, controlling, and detecting photons, which are particles of light”. Photonics explores a wider variety of wavelengths, from gamma rays to radio, including X-rays, UV and infrared light. The light-based technologies are used in medical diagnostics in many ways, like providing new tools for doctors and surgeons, new developments in optometry and vision science improve quality of life. And from smart phones to laptops to the Internet to lighting technology. Today, photonics is applied broadly in consumer electronics (barcode scanners, DVD players, remote TV control), telecommunications (internet), health (eye surgery, medical instruments), manufacturing industry (laser cutting and machining), defense and security (infrared camera, remote sensing), entertainment (holography, laser shows) – to name a few. The link as under give details on the Opportunities and Challenges for Photovoltaic (PV) Device Design, m Making Solar Cells a Reality in Every Home. http://ieeexplore.ieee.org/xpls/icp.jsp?reload=true&arnumber=6589128
According to a report, some 1.3 billion people in the developing and third-world countries depend on light using kerosene-oil lanterns and burners. This source of heat and light kill about 1.5 million people each year. It also imposes health hazard, which note that inhaling smoke from burning kerosene lamps is the equivalent of smoking four packs of cigarettes a day. During this International Year of Light, let there be a campaign of sharing this message to those underprivileged and their governments to provide safe and energy saving modern Light Emitting Diode (LED) lights as basis to convert energy in to heat and environmental friendly light.
The Science Film Festival invites audiences to discover the different roles light and its applications play in our everyday lives and what it reveals about the nature of the universe. The Festival is now open for submission until 13 March 2015. Films and programmes on all subjects and for all ages are welcome for consideration. The Science Film Festival is a collaborating Partner for the International Year of Light and Light-based Technologies (IYL 2015). http://www.goethe.de/ins/th/prj/wif/enindex.htm
The IYL Global Secretariat is located at the Abdus Salam International Centre of Theoretical Physics (ICTP). Contact: Joe Niemela Global Coordinator (IYL Secretariat)International Year of Light and Light-based Technologies 2015 [email protected]