Vijay Chandrasekharan is a research associate and doctoral candidate at the University of Florida, where he produced a micro-electronic sensor that measures the amount of shear stress created when turbulent air flows over a surface.

The sensor already has proven its usefulness in improving the basic understanding of turbulent flow in gases and liquids, and in characterizing wind tunnels.

When air flows through a wind tunnel, some air molecules stick to the wall of the tunnel while others flow through at the speed of the wind. The difference in speed exerts a drag force on the wall of the tunnel and causes friction in the air. Drag and friction are related to shear stress.

The new sensor can measure a wider range of shear stress than can any sensor of its type before.

Accurate measurements of shear stress are crucial to NASA's and aircraft manufacturers' research into developing more efficient airplanes. Shear stress affects the amount of drag on an aircraft. The more drag there is on an aircraft, the more fuel that aircraft burns.

Designers can use data from the sensors to design safer and more fuel-efficient aircraft.

There also are potential applications for this sensor in the fields of medical and environmental sciences. In medicine, for example, according to Chandrasekharan, the sensor could measure variations in shear stress along the wall of an artery and help researchers determine the effect those fluctuations have on the development of arteriosclerosis, commonly known as hardening of the arteries.

Chandrasekharan said the shear stress sensor is "one of the most successful efforts on direct shear stress sensors in published literature" and has a real shot at successfully entering the commercial market.

The sensor innovation is the result of a NASA Research Announcement, or NRA, study contract awarded by the Subsonic Fixed Wing Project of NASA's Aeronautics Research Mission Directorate. The directorate awards dozens of contracts for NRA studies to academia each year. This three-year contract with the University of Florida was worth $475,000.

"This collaboration led to an extremely satisfying experience for me as I worked on my dissertation," Chandrasekharan said. "Without NASA’s involvement my Ph.D. could have been strictly an academic pursuit, without subsequent practical, real-world importance."

Experts outside NASA and the aeronautics community already have taken notice of the sensor, its potential, and its inventor. Chandrasekharan recently received one of 13 national postdoctoral entrepreneurial fellowships awarded by the Kauffman Foundation.

"The work done by Vijay and this NRA's principal investigator, Mark Sheplak, is a great example of how NASA can work with a university to overcome fundamental challenges and lead to the improved safety and efficiency of our nation's aircraft," said Project Scientist Richard Wahls.

Chandrasekharan, Sheplak and two associates have filed a provisional patent application for the sensor.

Even as the original effort is lauded, a sequel to the story already is in work. As part of NASA's Graduate Student Researchers Program one student is working to further develop the sensor's electronic interface, while another is working on the wireless version of the sensor and recently performed tests with the sensor in a wind tunnel at NASA's Langley Research Center in Hampton, Va.

"It's good to see that our initial work has lead to synergistic outcomes at different levels through this NRA and other NASA programs," Chandrasekharan said.

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Washington, D.C. normally averages only 16 inches of snow per year, but this year most of the season's snowfall arrived over several days and the Geostationary Operational Environmental Satellite called GOES-12 captured the storms.

NASA's GOES Project created a movie of GOES satellite data from February 1-16, 2010 when two blizzards hit the Baltimore, Md. and Washington areas. The GOES-12 operated by the National Oceanic and Atmospheric Administration (NOAA) captures images of U.S. East Coast weather continuously. Those images were compiled into a movie by the NASA GOES Project at NASA's Goddard Space Flight Center, Greenbelt, Md.

"It is a pleasure to see the fruits of the hard work and commitment from the NASA and NOAA team," said Andre Dress, GOES N-P NASA Deputy Project Manager, at NASA Goddard. "These images are very impressive and I am excited to think that these were taken with the older satellites. NOAA plans to put into service the newer GOES N-P design, this April. I know we will be seeing better and more exhilarating images this year," Dress said.

During the first two weeks of February, heavy, wet snows semi-paralyzed Washington. Five inches fell on February 3, 24 inches fell on February 6, and 12 inches on February 10. A second storm followed on February 16 that dumped 10 inches on Philadelphia and New York, but spared Washington and Baltimore.

These storms are called "Nor'easters" because the counter-clockwise circulation around a low pressure system on the Atlantic coast pushes moist sea air from the north-east into arctic air over the land. This windy mixture creates a very efficient snow-making machine from Boston to Washington. "The GOES movie illustrates how succeeding storms form along the Gulf coast, travel up the Atlantic coast, pause over the mid-Atlantic states, and finally slide out to sea," said Dennis Chesters of the NASA GOES Project.

This movie was created by overlaying the clouds observed several times per hour by NOAA's GOES Imager onto a true-color map previously derived from NASA's MODIS land-mapping instrument. The infrared channels on GOES detect clouds day and night, which are portrayed as grey for low clouds and white for high clouds. During the day, the visible channel on GOES adds shadow-texture to the clouds and illuminates the snow on the ground.

The movie compresses 16 days into 2 minutes. It illustrates how continental-scale land/sea/air phenomena come together to make large winter storms. NOAA's ground/space-based observing system and numerical weather models did an excellent job of accurately forecasting the location and depth of each East Coast blizzard in this series.

Related Links:

> GOES Blizzard movie
> GOES Programs
> GOES-15

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Entitled "The Organic Continuum from the Interstellar Medium to the Early Earth," the two-day workshop held March 11-12, 2010 was organized by George Cody, leader of the NAI's Carnegie Institution of Washington team and Doug Whittet, leader of the NAI’s team at the Rensselaer Polytechnic Institute, Troy, New York.

Among the countries represented at the workshop were Canada, Mexico, six western European nations, Ukraine, India, South Korea, Japan, Australia, Brazil, Colombia, and Uruguay.

"The Workshop was in many ways a realization of the original vision of the virtual institute,"said Carl Pilcher, director of the NAI. "When the NAI began 12 years ago, we envisioned scientists interacting seamlessly at a distance. But the technology and the culture weren't ready. Today the technology works beautifully, and people have come to see this as the wave of the future. This workshop demonstrated that the future has arrived."

A total of 33 scientific talks were presented during the workshop, with interactive question and answer capability provided for the participants at eight sites equipped with high definition video and audio, and streaming with real-time question submission through the Adobe Connect web interface.

"The advances in technology that made this meeting possible have been paralleled by remarkable developments in the research that drives the science," Whittet said. "The benefit in terms of scientific knowledge gained and dollars expended by participants is likely unprecedented," added Cody.

According to Cody, the conference was "an experiment." Most participants categorized their experience level with remote collaborative technologies as beginner or intermediate, and a few had no prior experience at all.

Despite this, participants reported the experiment was a great success. "I was not expecting to have the same intellectual experience as I normally do at conferences…but after this conference, I do have that same sense of having been to a "real" conference,” adding, "this was very fulfilling for me professionally," said one participant.

Locations of participants ranged from a conference room in a major city with high-speed connectivity and professional videoconferencing equipment, to a home office in a small town with a laptop and home-based Internet connection.

"Over the course of the conference, I actually came to be unaware of the conference as being at multiple venues,"Cody said, "…the difference that high definition, high band-width videoconferencing makes is remarkable. Clear face-to-face contact with no time lag in either visual or audio was the essential part. Evidently the difference between 100 feet and 3000 miles is not all that great."

NAI is preparing guidelines for those in the community who are interested in hosting such an event in the future. Information will be available shortly, but interested parties can contact Marco Boldt at NAI Central at any time, marco.boldt@nasa.gov

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"I sort of slept. I was really excited," Ramesh recalled.

The sleepy-eyed students were prepared to conduct an experiment studying the effects of airflow resistance or "drag" of automobiles for the Santa Clara Valley Science Engineering Fair – 2010 Synopsys Championship held recently.

Ramesh called the education office at NASA Ames and was surprised when he got a phone call back that his visit had been approved. Both Ramesh and his best friend, Aiyaswamy, were invited to visit the Fluid Mechanics Laboratory at NASA Ames to perform their project.

"This is NASA and they called me back. I was surprised. We weren’t expecting them to call back," Ramesh said.

"I don’t think that they will ever forget this. This is a once in a lifetime experience for them," ventured his father, Ramesh Nagar.

The boys were fortunate to request their visit when the Fluid Mechanics Laboratory was uniquely set up to accommodate their request. Kurtis Long, test engineer at the Fluid Mechanics Lab got permission from Rabindra Mehta, chief of the Experimental Aero-Physics Branch, for the boys to visit and Long donated his time during his lunch hour when the boys performed their test.

"This is the perfect age at which we can effectively help, inspire and guide the next generation towards a future with NASA," said Mehta.

"These boys just happened to ask at the right time. If you don’t ask, you’ll never get what you want. It’s a scary thing to call NASA and ask for help with an experiment,” said Long. “These boys are really amazing and showing great initiative." Aiyaswamy’s life science teacher, Leslie Schafer, said that Aiyaswamy "is very motivated and talks a lot about his experience at Ames."

The two young students both showed up for their experiment with a half dozen toy cars they found at home. "Our project is to find the best design shape that has the least amount of drag," said Aiyaswamy. "As we began the experiment, we realized that cars with a sloping shape perform better."

The boys placed the cars in a pool of water. Dye was added to the water and photos were taken of the dye flowing around the toy cars. "Air and water have the same flow characteristics, but by using water we can slow down time and see the flow more clearly," explained Long. With these photos, the boys could measure the drag of each car. "These are real, no kidding, NASA photos," smiled Long.

The boys were assisted by Christina Ngo, an intern from the Foothill / De Anza college program. "I wasn’t surprised the students were allowed to visit. They love kids here," said Ngo.

During their visit, the boys learned about aerodynamic principles that will help them with their project. "We learned about separation points and what principles a car has to have for minimum drag," said Ramesh. The boys walked away from their lunch hour experiment with an entirely different hypothesis regarding their experiment. "This is why we do experiments," explained Long.

"I think the coolest part of this is the way that NASA responded. Top scientists showing an interest in two middle school kids from San Jose. That's more impressive than anything else," Nagar said. The boys enjoyed their time with the scientists. "We really enjoyed the whole NASA experience - the people, as well as the lab. It was like being part of the NASA team for a day," Ramesh added.