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19 September 2014

Photons for inspiration, fuel -- and light!

The many properties of light have long provided
inspiration for SPIE CEO Dr. Eugene Arthurs.
Editor’s note: A green laser lighted the early career path of then-physics-graduate Eugene Arthurs, now CEO of SPIE, the international society for optics and photonics. Light from many sources continues to provide him with inspiration and direction, Dr. Arthurs writes in this blog post originally published in the International Year of Light blog, www.light2015blog.org.

Looking back, my career path was not determined by some grand plan, but rather by the beauty of the light from an argon ion laser in our Applied Physics department at Queen’s University Belfast. It wasn’t the science that the laser was bought for, Raman spectroscopy, or an understanding of how the laser would change the world, that drew me.

At the time I was soon to graduate with a physics degree – the first in my family history to get a science degree – and was interviewing with a local branch of IBM where my love of mathematics might give me an edge and where I might find stimulating work in Northern Ireland.

But fate intervened and I was seduced by the light, by the pure intense green beam, and lasers became my thing. Mentioning lasers also gave some sort of defense against the many enquiries from caring relatives on when was I going to get a real job.

Another indelible memory; an important insight came to me in 1980 when I was at the home of my boss at the time, Dick Daly, founder of an early laser company. It was the fall (autumn to some) on Long Island, New York, which meant leaves everywhere. Dick pointed to one of his huge piles of leaves and said with his characteristic grin, “One of my photon stores.”

The concept of storing photons was of great interest to laser jocks like Dick and me. Short-pulse high-power lasers benefit greatly from materials that can hold a lot of energy. But Dick’s observation was way beyond the world of lasers and has caused me to think since about the profound relationship between light and life.

The chloroplasts in leaves use the photons from the sun to convert carbon dioxide into oxygen and carbon. All of our forests, our plants have been busy “sequestering” carbon dioxide for hundreds of millennia, while tuning our atmosphere to be human-friendly.

It takes the energy from many photons to grow a leaf, but at the end of the day, what a leaf is, is mostly a carbon-based organic structure built by light. This lesson from one of my many mentors led me to realize that as all fossil fuels started as vegetation, we are burning our way through Earth’s store of photon energy from the sun, accumulated over 300 million years or more.

With many processes and great lengths of time, nature has stored this photon energy from leaves, wood and other biomass in high-density forms such as oil and coal. The high density is key to modern transportation, and collection of fuel for large centralized power plants.

Now we have a formidable challenge to capture and store solar energy arriving today in ways that will challenge nature’s gifts. Nature had all that time to store photons; our version of solar energy is more “real time.” But the sooner that solar becomes a significant part of the global energy mix, the better for our planet, for all of us.

Aside from SPIE, Dr. Arthurs is also a member of the Photonics21 Board of Stakeholders, where he is directly involved in the European Commission’s Horizon 2020 and the entity for a public-private partnership (PPP). Prior to these responsibilities, Eugene has held many positions at esteemed scientific technology organizations in both the US and Europe, and has served on several boards in the realm of optics, photonics, and scientific development.

12 September 2014

Ozone layer is recovering, satellite data says

Worldwide action to phase out ozone-depleting substances has resulted in remarkable success, according to a new assessment by 300 international scientists released on 10 September. The stratospheric ozone layer, a fragile shield of gas that protects Earth from harmful ultraviolet light, is on track to recovery over the next few decades.


The most current ozone hole satellite data comes from the Ozone Monitoring and Profiler Suite (OMPS) instrument on the NASA-NOAA Suomi National Polar-orbiting Partnership satellite, known as Suomi NPP, and the Ozone Monitoring Instrument and Microwave Limb Sounder on NASA's Aura satellite. The full report will be available in early 2015.

Suomi NPP is part of NOAA’s next generation Joint Polar Satellite System (JPSS) constellation of polar-orbiting environmental satellites. Suomi NPP, launched in October 2011, provides continuity for NASA’s Earth Observing System (EOS) and is a bridge between NOAA’s legacy Polar Orbiting Environmental Satellites (POES) and the JPSS-1 satellite, now being built and integrated at the Ball Aerospace spacecraft manufacturing facility. NPP’s sensors have surpassed expectations for low noise and accuracy, and have provided useful data to forecasters beginning well before it gained operational status. Suomi NPP data, in conjunction with other polar weather satellite data, were essential to predicting the path of 2012’s Hurricane Sandy more than four days in advance. Suomi NPP extends the range of global forecasts three to seven days in advance of significant weather events.

In May 2014, NOAA’s Satellite and Information Service named Suomi NPP as its primary operational polar-orbiting satellite system for NOAA’s day-to-day operations. In 2012, NASA renamed NPP in honor of the late Verner E. Suomi, a meteorologist at the University of Wisconsin who is recognized widely as "the father of satellite meteorology."

OMPS, an advanced suite of three hyperspectral instruments, extends the 30-plus year total-ozone and ozone-profile records. OMPS products, when combined with cloud predictions, also help produce better ultraviolet index forecasts. Designed and built by Ball Aerospace, OMPS is one of five instruments that launched aboard Suomi NPP in 2011. A second OMPS flight unit built by Ball Aerospace will fly on the Joint Polar Satellite System-1 (JPSS-1) with its expected launch in 2017.

OMPS consists of a nadir mapper that will map global ozone with about 50-km ground resolution, a nadir profiler that will measure the vertical distribution of ozone in the stratosphere, and a limb profiler that measures ozone in the lower stratosphere and troposphere with high vertical resolution.

Sarah Lipscy is chief instrument scientist for OMPS at Ball Aerospace. OMPS measures ozone in our atmosphere from Suomi NPP. She leads a data-analysis team to characterize the OMPS performance in meeting pre-launch requirements. Lipscy received her PhD in astrophysics from UCLA. She studied the evolution of massive stars, and now works with space sensors that look back at Earth. She co-authored an open-access paper in the SPIE Optical Engineering journal (September 2013) entitled “New paradigm for rapid production of large precision optics: frozen membrane mirror technology.”

See a pre-launch profile of all five NPP instruments in the SPIE Newsroom.