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Dr. Stephen Hammel, scientist,  at the Space and Naval Warfare Systems Center Pacific. (photo by Alan Antczak/released) (Photo by Alan Antczak/Released)

Dr. Stephen Hammel, scientist, at the Space and Naval Warfare Systems Center Pacific. (Alan Antczak courtesy photo)

WHO: Dr. Stephen Hammel.  Originally from New Mexico.  Enjoys the great outdoors, the mountains and LASERS.  Leading a group that studies atmospheric optics at SPAWAR.

TITLE: Scientist at the Atmospheric Propagation from the Space and Navy Warfare Systems Center Pacific (SSC Pacific).

MISSION: To study how light goes through the atmosphere, Dr. Stephen M. Hammel developed models to represent the degrading behavior of aerosols, turbulence and refraction on propagating electro-optical/infrared beams in the maritime environment.  Basically, he made a model to help laser beams shoot sure and true.

Recently, Dr. Hammel was one of SPAWAR’s 2014 Delores M. Etter 2014 Top Scientist and Engineers of the Year award winners.  He thinks that science is a collaborative effort, and believes that his group is one of the ones showing that scientists who are collaborative can flourish.  A point proved thanks to his model which helps deployed forces to effectively address the growing risk from adversary aerial and sea surface platforms.

Explain to me the models you developed to represent degrading behavior in the maritime environment.

“Everything that we do is to study what the atmosphere – and particularly the atmosphere over the ocean – does to propagating beams.” – Dr. Hammel, SSC Pacific scientist

“There are two major things that happen when we’re trying to propagate light over the ocean.  One of the big things is aerosol.  From the surf line you’ll see a haze sometimes, but even in the open ocean you’ll see the effects of breaking waves makes a misty or hazy condition.  That interferes with the light going through.  Some of our models have to predict how the aerosol factors can affect light.  We also worry about this in the Middle East.  Sometimes aircraft operations are hampered by dust storms that blow over water surface.  The dust from land is also a kind of aerosol.  These are particles that take light out of the beam we’re interested in propagating, or just make it difficult to see very far along a line of sight.  That’s the first part.”

Part two is what turbulence will do.  Turbulence is sometimes hard for people to imagine, but if you look over a dark, asphalt road when you’re driving every day you’ll see mirage effects sometimes from that turbulence layer.  You’ll also see distortions.  Waves; an image seeming to break up and wave back and forth.  That’s a turbulence effect.  Both of those things are very, very important because they both hamper our ability to send light from point one to point two.”

What is the goal/mission of these models and what do you hope it will achieve?

“What I would like to be able to do, ultimately, is predict how well an optical system is going to work before we use it.  I would call that the ‘prediction phase’.  One of the projects is called ‘Solid State Laser’ funded by the Office of Naval Research.  This is a new and very active area right now for ship defense that uses high-energy lasers.  For these systems, especially something that involves possible life-or-death kinds of decision-making, I would love to tell that captain, at any point in time, how well his system is going to work for any kind of mission that he may have in mind.  That is my goal, and we are working our way slowly toward that kind of a goal.  We are also very interested in communications systems using light.  A fantastic amount of information can be carried through light [compared to radio frequency channels].”

In your own words, what is it about this technology that makes it so significant?

“It’s significant because the end results are really profound. Being able to use lasers, for example, would really change the way ships right now are fitted and sent to sea.  A ship with a laser defensive system would have an infinite magazine.  Having a finite or small number of missiles really affects how you engage in the fleet.  Likewise, you would also have much more control of intensity.  It’s really a dial up of how much and how strong.  I think that’s very promising. Optical communications hold a lot of promise too because there are so many different possibilities.  Right now  everybody desires higher speed communication links, so I think that’s also a very significant application area.”

Could you use these models “on the fly”, or is it something that has to be figured out before hand?

“The answer is yes to both of those.  Our models are not so streamlined yet, and we don’t even have application areas quite in place yet, but that is definitely the goal.  I want our work to be fast enough and well-enough understood so it could be used on-the-fly.” (He adds that this would be several years down the road from where they are now.)

This reminds me of the computer on Star Trek.  When they say, “Computer, will shooting this asteroid destroy the planet?” the computer is able to create a model on the spot and give them the odds of success/failure.  Are you hoping to have it be something like that?

“Precisely.  That’s ultimately my kind of dream.  To be able to be part of the team that developed that kind of capability, I would consider myself very successful.  We’re working our way toward that.  That’s where we want to be.”

How could you use information derived from the models to aid the military or help with military missions?

“This fall, when we test the first iteration of the ship defense laser going onto a ship, right away [the military is] going to want to know how effective will this be.  It will be something of an on-the-spot question, as you suggested.  They will need to know if they can go a certain distance, with a certain amount of effectiveness.  That’s where the model has to work.”

“The part that I haven’t said much about so far is what do we have to give the model to make it work?  The answer to that is we use local meteorological conditions, generally.  We measure air temperature, water temperature, and relative humidity. Sort of like a small weather station.  The second part is with numerical weather predictions, just like your nightly news weather.  The Navy has a very extensive program that gets all ships forecasts for any maritime area of interest.  We want to use that numerical weather prediction because it requires a lot of computer capacity back on land to feed that back out to the ships.”  (I call this “factoring the variables”, btw.)

What do you think is the most impressive/beneficial thing about this and why?

“There are all sorts of applications: if we look through a telescopic lens and see a blurry image, or difficult-to-discern images, our first question is to find out more about the process that caused the blur.  I think that’s where we’re drilling further and further into determining how turbulence causes the image to distort, and we are learning how to overcome that in the right situations.”

Will these models be able to identify new problems, and able to learn and grow with new challenges?

“I think the models will definitely evolve.  As we get more advanced, they will be able to provide more local and high definition kinds of predictions.  I also think techniques that we want to use to mitigate these factors can be developed and made better and better.  Right now there is a whole area of optics called adaptive optics.  This is not what I do but my model would hopefully be a part of that chain.  They use these to clean up imagery.”

“For example, telescopes that are looking at stars, and see only a blurry mess, can actually reverse that blur sometimes by using the right kind of information about the turbulent layer between us and the star.  So that’s a vision of where we could both go in communications links and system development.  We want to keep the links clean and tightly defined, or the images sharp.  Both of those would benefit from that kind of knowledge and mitigation strategy like that.”

“It’s always important to know, and to gauge, just how much energy you have precisely,” says Dr. Hammel.  “The next generation of ships are essentially the electric ship model.  I think it’s a beautiful way because you can quickly divert the energy from one unused system to another operation that critically needs energy.  And with the proper model you know how much you need for how long.”

If you could go anywhere in time and space, where would you go and why?

“I have to say that I would like to go into space for three weeks, and be weightless, and be able to see Earth.  I’d probably like to go to the moon, and then go back to orbit, and then star in space until my vacation was done.  I wouldn’t want to stay there forever, or even two years.  Three weeks is just about the right amount of time.”

Thanks to Dr. Stephen Hammel for contributing to this article, and for his contributions to the science and technological communities.

Read More!  Check out some of Dr. Hammel’s public release reports.  You can read them here and here.


Jessica L. Tozer is the editor and blogger for Armed with Science.  She is an Army veteran and an avid science fiction fan, both of which contribute to her enthusiasm for science and technology in the military.

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