Andrew Peterson named Young Investigator

Andrew Peterson, assistant professor of engineering, has won a Young Investigator Award from the U.S. Navy. Peterson, one of only 26 young faculty nationwide to be selected, was recognized for scientific pursuits that show exceptional promise for the Navy and Marine Corps. The award is intended to promote the researcher’s professional development; Peterson will receive three years’ funding for research that could advance naval technology, the Navy announced Tuesday, March 27.

Peterson joined the Brown faculty in January. His primary research is devoted to figuring out how to produce carbon-based fuels from renewable sources. A key to such a breakthrough lies in overcoming the steep energy threshold needed to split carbon dioxide molecules into hydrocarbons. Peterson’s approach is to rely on quantum mechanics calculations to design catalysts to make those reactions more efficient and less costly.

Brown to host advanced materials conference

Brown University has organized a conference to explore the frontier of advanced materials. The all-day gathering on Thursday, March 29, 2012, features talks and discussions by leading innovators and scientists in industry, academia, and the federal government. The meeting stems from a call by President Obama for American companies to develop advanced materials at twice the speed as currently possible and at a fraction of the cost.

Cyrus Wadia“The federal government cannot by itself ensure that America remains the leader in this important sector.”Cyrus Wadia
“The federal government cannot by itself ensure that America remains the leader in this important sector.”
PROVIDENCE, R.I. [Brown University] — Last June, President Obama announced the Materials Genome Initiative, an ambitious effort to assist American companies to develop advanced materials at twice the speed as currently possible and at a fraction of the cost. The proposal stems in part from the startling losses in employment and technology that have beset the U.S. manufacturing sector and is intended to reposition America as a leader in producing advanced materials from safer, lighter vehicles to solar cells as cheap as paint. In a new funding request for next fiscal year, Obama seeks more than $100 million to continue the initiative.

Hoping to capitalize on the momentum, Brown University has organized a conference on March 29, 2012, to explore synergies and research opportunities in advanced materials. The all-day gathering features talks and discussions by leading innovators and scientists in industry, academia, and the federal government.
The meeting takes place on the Brown campus at the Salomon Center for Teaching, on the College Green. An agenda, list of speakers and other information is available online.
Cyrus Wadia, assistant director for clean energy and materials research and development in the White House Office of Science and Technology Policy, will give the plenary address. He will talk about how advanced materials are essential to economic security and human well-being.
“The Materials Genome Initiative will speed the discovery and development of many of those materials, and I will explain why the federal government cannot by itself ensure that America remains the leader in this important sector and why success will depend on a wide range of stakeholders and efforts, including regional efforts like those at Brown University,” Wadia said.
Other speakers and panelists will explore:
  • new materials for automobiles, aerospace, energy conversion/storage, microelectronics and medical devices;
  • emergent computational and experimental approaches;
  • strategies for sharing, storing, and searching materials data;
  • best practices for industry/university/government collaborations.
“Brown’s hosting of this meeting highlights the important role that the University can play in building strong research initiatives in this area,” said Clyde Briant, vice president for research. “The focus on the Materials Genome Initiative is an area where Brown already has great research strengths and one that should help us build partnerships with many other industries and universities.”
“Brown engineering’s unique interdisciplinary culture is ideally suited for producing new breakthroughs in advanced materials,” said Lawrence Larson, dean of engineering. “These breakthroughs often occur at the boundaries between traditional disciplines, like materials science, mechanical engineering, or electrical engineering. We look forward to developing exciting new collaboration opportunities that will result from this conference.”
The Materials Genome Initiative is connected to a larger call announced by Obama last summer to enlist industry, universities, and the federal government to invest in emerging technologies that will create manufacturing jobs and enhance U.S. competitiveness. Earlier this month, the president also asked for $1 billion to create a National Network for Manufacturing Innovation, to fund up to 15 regional hubs of manufacturing excellence.
“I’m calling for all of us to come together — private sector industry, universities, and the government — to spark a renaissance in American manufacturing and help our manufacturers develop the cutting-edge tools they need to compete with anyone in the world,” Obama said in a speech last summer. “With these key investments, we can ensure that the United States remains a nation that invents it here and manufactures it here and creates high-quality, good-paying jobs for American workers.”
The Materials Genome Initiative would direct funding to the Department of Energy, the Department of Defense, the National Science Foundation, and the National Institute of Standards and Technology. The initiative will fund computational tools, software, new methods for material characterization, and the development of open standards and databases that will make the process of discovery and development of advanced materials faster, less expensive, and more predictable.

President-Elect Paxson Visits School of Engineering

On Tuesday, March 20, Dean Larry Larson had the pleasure of leading President-Elect Christina Paxson on a tour of Barus and Holley, Prince Lab, and the Giancarlo Labs. This was the President-Elect’s first extended visit to campus since her selection as the University’s 19th President on March 2. During the visit, Paxson also met with senior administrators and faculty members and toured the libraries.

During her tour of the School of Engineering, President-Elect Paxson had the opportunity to meet many professors, graduate and undergraduate students, and staff, and see demonstrations of some of the research that is being conducted at the School.

Outstanding faculty members Arto Nurmikko, Gabriel Taubin, Ben Kimia, Rashid Zia, Chris Bull, Kenny Breuer, and Nitin Padture explained some of their ongoing research projects to the President-Elect.

She also had the opportunity to sit in on Professor Allan Bower’s freshman EN0040 class, where she was able to see student presentations.

“Having the opportunity to present our project to President-Elect Paxson was wonderful, not only because she had a very friendly and amiable demeanor, but also because she showed evident appreciation for our ideas,” said Emily Toomey ’15.

“Although the project at first seems like it has a simple objective, it required a great deal of collaboration, creativity, and application of engineering principles to create a successful result. By asking questions about our thought processes and how the MATLAB functions worked, President-Elect Paxson displayed a genuine interest in our efforts that made the project even more worthwhile,” added Toomey.

“What I enjoyed most about President-Elect Paxson's visit was the genuine interest that she showed in understanding our project,” said Maggie Coats-Thomas ’15. “The questions that she asked made it clear that she understood what was going on and appreciated our efforts, which I thought was very rewarding. She was very friendly and I am so pleased I got the opportunity to interact with her so soon after she was elected.”

The tour also provided the new President-Elect with the opportunity to see some of the space and facility constraints and challenges that currently exist in Barus & Holley. In an interview with the Brown Daily Herald, Paxson said of engineering, “it is clear that they’ve had a lot of growth, but they’re very tight on space.”

Overall, the tour was a great success in showcasing both the exciting work that is happening in the School of Engineering, and the need for expansion and growth.

‘Bed-of-nails’ breast implant deters cancer cells

Researchers at Brown University have created an implant that appears to deter breast cancer cell regrowth. Made from a common federally approved polymer, the implant is the first to be modified at the nanoscale in a way that causes a reduction in the blood-vessel architecture that breast cancer tumors depend upon, while also attracting healthy breast cells. Results are published in Nanotechnology.

PROVIDENCE, R.I. [Brown University] — One in eight women in the United States will develop breast cancer. Of those, many will undergo surgery to remove the tumor and will require some kind of breast reconstruction afterward, often involving implants. Cancer is an elusive target, though, and malignant cells return for as many as one-fifth of women originally diagnosed, according to the American Cancer Society.

A selectively inhospitable surface
A bumpy “bed of nails” surface does not allow cancerous
cells to gather the nutrients they need to thrive — possibly
because cancerous cells are stiffer and less flexible than
normal cells, which can manage the bumps and thrive.

Credit: Webster Lab/Brown University
Would it be possible to engineer implant materials that might drive down that rate of relapse? Brown University biomedical scientists report some promising advances. The team has created an implant with a “bed-of-nails” surface at the nanoscale (dimensions one-billionth of a meter, or 1/50,000th the width of a human hair) that deters cancer cells from dwelling and thriving. Made out of a common federally approved polymer, the implant is the first of its kind, based on a review of the literature, with modifications at the nanoscale that cause a reduction in the blood-vessel architecture on which breast cancer tumors depend — while also attracting healthy breast cells.

“We’ve created an (implant) surface with features that can at least decrease (cancerous) cell functions without having to use chemotherapeutics, radiation, or other processes to kill cancer cells,” said Thomas Webster, associate professor of engineering and the corresponding author on the paper in Nanotechnology. “It’s a surface that’s hospitable to healthy breast cells and less so for cancerous breast cells.”

Webster and his lab have been modifying various implant surfaces to promote the regeneration of bone, cartilage, skin, and other cells. In this work, he and Lijuan Zhang, a fourth-year graduate student in chemistry, sought to reshape an implant that could be used in breast reconstruction surgery that would not only attract healthy cells but also repel any lingering breast-cancer cells. The duo created a cast on a glass plate using 23-nanometer-diameter polystyrene beads and polylactic-co-glycolic acid (PLGA), a biodegradable polymer approved by the FDA and used widely in clinical settings, such as stitches. The result: An implant whose surface was covered with adjoining, 23-nanometer-high pimples. The pair also created PLGA implant surfaces with 300-nanometer and 400-nanometer peaks for comparison.

In lab tests after one day, the 23-nanometer-peak surfaces showed a 15-percent decrease in the production of a protein (VEGF) upon which endothelial breast-cancer cells depend, compared to an implant surface with no surface modification. The 23-nanometer surface showed greater reduction in VEGF concentration when compared to the 300-nanometer and 400-nanometer-modified implants as well.

It’s unclear why the 23-nanoneter surface appears to work best at deterring breast-cancer cells. Webster thinks it may have to do something with the stiffness of malignant breast cells. When they come into contact with the bumpy surface, they are unable to fully wrap themselves around the rounded contours, depriving them of the ability to ingest the life-sustaining nutrients that permeate the surface.

“This is like a bed-of-nails surface to them,” Webster said.

“I would guess that surface peaks less than 23 nanometers would be even better,” Webster added, although polystyrene beads with such dimensions don’t yet exist. “The more you can push up that cancerous cell, the more you keep it from interacting with the surface.”

The pair also found that the 23-nanometer semispherical surface yielded 15 percent more healthy endothelial breast cells compared to normal surface after one day of lab tests.

Webster and Zhang next plan to investigate why the nanomodified surfaces deter malignant breast cells, to create surface features that yield greater results, and to determine whether other materials can be used.

The National Institutes of Health’s National Center for Research Resources and the Hermann Foundation funded the research. Michael Platek at the University of Rhode Island helped with the electron spectroscopy for chemical analysis.

- by Richard Lewis

Engineering Graduate Student Fatih Calakli Wins Advanced Surface Reconstruction PCL Robotics Code Sprint 2012

Brown University School of Engineering graduate student Fatih Calakli has won the Advanced Surface Reconstruction PCL Robotics Code Sprint 2012, sponsored by Sandia National Labs.

Fatih is a student of Professor Gabriel Taubin whose group has made extremely important contributions to surface reconstruction, 3D compression, and object recognition.

The goal of this project is to make our state-of-the-art surface reconstruction algorithms widely available as part of the Point Cloud Library (PCL).

The Point Cloud Library is a stand alone, large scale, open project for 3D point cloud processing which is getting widespread support and attention from industry and academia. For more information, please go to: http://pointclouds.org/

Brown Graduate Student Lucy Weng ScB'08 Wins Award at the Northeast Bioengineering Conference

Brown University biomedical engineering graduate student Lucy Weng ScB'08 recently won the Master's Student Competition at the 2012 Northeast Bioengineering Conference hosted by Temple University in Philadelphia. Overall, there were more than 200 papers accepted, and awards were given for best paper to two master's student and two Ph.D. students. Weng received a certificate and a $250 prize.

Her paper, “Nanophase Magnesium for Orthopedic Applications” discusses the use of magnesium as a biomaterial for orthopedic applications because of its biocompatibility, biodegradability, and positive effect on bone formation. Likewise, studies have shown nanophase material increase osteoblast (bone-forming cell) function compared to conventional materials, but the two have not been studied together. The purpose of this study was to determine if altering magnesium surface features into the nanometer scale promotes greater osteoblast functions.

Nanorough magnesium surfaces were created by a novel treatment with sodium hydroxide at 1N, 5N, and 10N concentrations for 10, 20, and 30 minutes. Material characterization by scanning electron microscopy showed increased roughness on all treated samples compared to the control magnesium. Contact angle measurements indicated greater hydrophilicity on treated magnesium and no significant effect of ultraviolet sterilization on the surface energy of the material. Osteoblasts were seeded onto treated and untreated surfaces and adhesion at 4hrs were assessed through the MTT assay.

Results indicated increased osteoblast adhesion on nano-treated samples compared to untreated samples. These findings support previous studies indicating the promise of magnesium as a biomaterial for orthopedic applications and suggest further experiments examining the long-term effects of nanophase magnesium on osteoblast proliferation and function.

Building a better battery via technology crowdsourcing

Brown is one of the first participants to join Allied MindStorm, an open innovation website that invites the public (thinkers) to brainstorm new commercial applications around exciting technologies (challenges) developed by university researchers. In its initial submission on a Paper-Thin Plastic Battery Mashup, the public is invited to participate in postulating on new uses of the technology in the open innovation setting.

The new battery device submitted uses plastic, not metal, to conduct electrical current. It combines the power of a capacitor with the storage capacity of a battery. Tayhas Palmore, professor of engineering, worked with a team to develop the new type of battery that is a hybrid. It can store and deliver charge over long periods of time with greater power and with twice the storage of a double-layer capacitor.

Its power and paper-thin dimensions could be used for wrapping electronic devices but also be made into a fabric-like material. A description of the prototype is published in Advanced Materials: 18, 1764–1768.

Allied Mindstorm has a new website where university researchers can submit new technologies and then invites the public to come up with new applications for these technologies.

One of the first participants to join Allied MindStorm, Katherine Gordon, managing director of Brown University's Technology Ventures Office, said, "The decision regarding which application to pursue first is a complex and important one. Allied Minds is creating an entirely new way for universities to make this decision, while showcasing their most interesting research, but also improving them through open collaboration."


- Courtesy of the Technology Ventures Office

Three Biomedical Engineering Graduate Students Win Award

Brown biomedical engineering graduate students Gozde Durmus, Kim Kummer '11, and Erik Taylor were one of ten graduate student teams to win the Prize for Primary Healthcare Award (Phase I) from the Center for Integration of Medicine and Innovative Technology (CIMIT). The title of their project is "Using Nano-material Science to Inhibit Medical Device Infections".

Each winning team received $10,000, and they will now be able to use these funds to develop a final proposal over the next few months as they compete for the top three spots and a total of $300,000 in additional funds against teams from other top schools such as MIT, Johns Hopkins, and Yale.

“This is an outstanding achievement,” said Associate Professor Thomas Webster, “and places Brown among the top biomedical programs in the country.” Webster serves as the advisor to the three students on the research.

The award is for innovative technology ideas to improve the quality and efficiency of primary care in medicine. The Brown team was selected out of 76 applicants from 38 of the top engineering programs in the country. The goal of the competition is to stimulate the development of innovative technology to serve the needs of the frontlines of healthcare.

Johnson & Johnson Corporate Office of Science & Technology Grant to Seed Biomedical Research

Brown announced that it has received an unrestricted grant from the Johnson & Johnson Corporate Office of Science & Technology (COSAT) to extend its seed funding for scientific research projects that have the potential to benefit patients and the healthcare system. Working with COSAT, Brown will identify projects, such as potential therapies, devices, or diagnostics, and then Brown will match funds from the grant to support the research.

“We're tremendously excited about launching this new translational seed fund,” said Katherine Gordon, who directs the university’s technology ventures office. “The funding dedicated to the new initiative will support grants for promising programs that require funding for proof of concept, feasibility or translational studies. We're very appreciative of this funding." 

Brown will retain all intellectual property rights to the research.

Science - The Space Shuttle Design Concept - Idealized Functionality!

Stripped to the essentials, NASA's Space Transportation System (STS), the Space Shuttle, needed an Orbiter vehicle to accommodate crew and mission requirements, plus the propulsive power to accelerate many millions of pounds of personnel, hardware and fuel to orbiting velocity; plus all back-up, contingency and emergency equipment that could conceivably be necessary for foreseeable and unforeseeable exigencies. Among the forcing-functional-considerations (after the primary concern for safety and reliability) was cost and the minimization of factors which would necessitate long preparation periods between flights (the "shuttle" concept).

The Orbiter vehicle would house the astronauts as they circled Earth, containing also all requisite systems, materials, supplies and equipment for: life support during the voyage; communication with Earth; mission objectives (space experiments to be carried out); and requirements for the return to Earth: mechanisms for de-celeration from orbital speed, critical insulation or heat protection for the reentry phase, and means for flight control and landing upon a standard length runway (glider modus operandi, no propulsive power), and conventional control surfaces: wing flaps, rudder flaps, wheels and brakes.

The propulsive system evolved into a three engine configuration (providing increased reliability and stability), integrated into the Orbiter vehicle structure; engine fuel contained in a large central tank attached to the Orbiter (droppable when empty, with altitude-opening parachutes) and two strap-on solid rocket boosters (reliable gigantic "fire-crackers), droppable and recoverable from the ocean (similar parachutes). The propulsion system requirement was extremely demanding, to achieve lift-off and acceleration to reach orbit velocity, lifting over seven million pounds of total weight.

The most reliable and efficient configuration for assembly of the elements and for optimum launch sequence was quickly determined to be the two giant solid rockets bolted to the launch pad (huge explosive bolts anchoring the rocket flanges to the concrete pad); the Orbiter vehicle attached (removably) to the rockets; finally the gigantic fuel tank (removably) attached to the Orbiter. The launch sequence was initiated by firing of the on-board engines, then the firings of the solid rockets and their flange bolts exploded - separating the STS assembly from Earth. The Space Shuttle system would then rise, slowly at first and vertically, increasing in speed and altitude until clear of the Cape Canaveral launch facility, then adjusting to an angled horizontal climb; taking advantage of the direction of Earth's rotation (reducing the STS requirement to reach orbit speed) by about 1000 miles per hour. As the solid rocket boosters complete their firing, they are dropped, to be salvaged from the ocean for reuse. The orbiter engines continue to power the system until orbit is reached and the fuel tank is depleted, when it also is blasted free of the orbiter.

What is generally not known is that once the Shuttle drops its fuel tank, the orbiting vehicle no longer has propulsive capability - coasting along at 18,000 miles per hour in the vacuum of space. The mechanisms aboard the vehicle for maneuvering are the Space Shuttle Orbital Maneuvering System (OMS), a system of rocket engines used for final orbit injection, modification or maneuvering at the Space Station. The OMS consists of two protrusions at the back of the Shuttle, on either side of the vertical stabilizer. Each contains a hypergolic engine with 6,000 lb thrust and a specific impulse of 313 seconds. The OMS pods also contain the rear set of small reaction control system engines.

For the initial ventures into space, the Mercury and Apollo programs, the reentry approach was for "over-kill" - to protect the astronauts from the extreme heat of reentry by covering the bottom of the circular capsule (the face to reentry) with many inches of ablatable material, fiber-glass and resin, which melts and vaporizes, the transformation from a solid to a gas dissipating the enormous heat of reentry, protecting the astronauts. As the slowing capsule falls to a low altitude, a trio of parachutes is deployed - the capsule drops into the ocean, with a quick pick-up by naval vessels on close standby.

Assistant Professor Petia Vlahovska Wins Salomon Award

Assistant Professor of Engineering Petia Vlahovska was one of 15 faculty researchers who were honored on March 14 with a Salomon Award. The competitive grants come courtesy of the Richard B. Salomon Faculty Research Awards administered by the Office of the Vice President for Research (OVPR).

Clyde Briant, vice president for research, said the awards are primarily to stimulate new research projects by faculty. “We know oftentimes it’s hard to get (federal) funding” to begin major research projects, Briant said. “These funds are in place to help you do that.”

“We are the entity in modern society that’s charged with discovery,” said Provost Mark Schlissel, congratulating the award recipients. “This is what we thrive on, this is what we’re here for.” Schlissel, like Briant, noted that these awards are important for jump-starting complex research projects by getting preliminary data. “These awards help get research projects off the ground and get them competitive for further funding,” Schlissel said.

The Salomon Awards were established to support excellence in scholarly work by providing funding for selected faculty research projects of exceptional merit. Recipients receive as much as $15,000. The Salomon Awards have been administered by OVPR since 2003, and a total of about $2 million has been awarded to 132 faculty.

Vlahovska won a $15,000 award for her proposal, “Tension regulated phase separation in biomimetic multicomponent membranes.” Cells and cellular organelles are encapsulated by membranes composed of hundreds of lipids. This lipid diversity is essential for cell functions such as signaling: lipid mixtures organize into rafts, which serve as platforms for molecular-binding events at the membrane interface. Raft dynamics is regulated by physio-chemical variables like composition, temperature, and tension.

Vlahovska’s proposed research centers on the effects of tension on raft evolution and stability, which is virtually unexplored due to difficulties in tension control and quantification. Vlahovska proposes the use of electric fields and microfluidic flows to create well-defined tension conditions that will allow her to experimentally investigate lipid demixing and domain evolution in tense membranes. This knowledge will benefit bioengineering applications that exploit cell signaling machinery, such as targeted drug delivery.

Brown Professor Huajian Gao Receives Humboldt Research Award

Huajian Gao, Walter H. Annenberg Professor of Engineering at Brown University, has received a Humboldt Research Award from the Alexander von Humboldt Foundation in Germany. Award winners are invited to spend a period of up to one year cooperating on a long-term research project with specialist colleagues at a research institution in Germany. Professor Dr. Joachim P. Spatz nominated Professor Gao and is hosting him during his research in the Department of Biophysical Chemistry at the University of Heidelberg.

The award is granted in recognition of a researcher's entire achievements to date to academics whose fundamental discoveries, new theories, or insights have had a significant impact on their own discipline and who are expected to continue producing cutting-edge achievements in the future.

“This is a great award for Professor Gao,” said Dean Larry Larson. “He is one of the leading researchers and professors in his field, and that continues to be recognized on both a national and international level. We are fortunate to have him at Brown.”

Professor Gao received his B.S. degree from Xian Jiaotong University of China in 1982, and his M.S. and Ph.D. degrees in engineering science from Harvard University in 1984 and 1988, respectively. He served on the faculty of Stanford University between 1988 and 2002, where he was promoted to associate professor with tenure in 1994 and to full professor in 2000. He was appointed as Director and Professor at the Max Planck Institute for Metals Research in Stuttgart, Germany between 2001 and 2006. He joined Brown University in 2006. Professor Gao has a background in applied mechanics and engineering science. He has more than 25 years of research experience and more than 300 publications to his credit. In February of 2012, he was elected to the National Academy of Engineering (NAE).

Professor Gao’s research group is generally interested in understanding the basic principles that control mechanical properties and behaviors of both engineering and biological systems. His current research includes studies of how metallic and semiconductor materials behave in thin film and nanocrystalline forms, and how biological materials such as bones, geckos, and cells achieve their mechanical robustness through structural hierarchy.

Plasma Engines - How The Workings Of The Everyday Fluorescent Light Gets Us To Other Planets

Everyone has seen a fluorescent tube light, the kind that are used in your kitchen or office and are more energy-efficient than the standard filament light bulbs.

The light itself uses a number of electrical processes that are similar to those used to generate thrust from a plasma engine in space, yet few of us would make the connection between the two. A way to look at it is this: the process that lights a lot of public and private spaces is almost identical to the process that can propel a spacecraft towards another planet or in the case of the NASA probe, Deep Space 1, can propel a craft to speeds never achieved previously in space travel. Plasma engines are viewed as next-generation technologies, with large-scale thrusters currently being developed for possible use on interplanetary missions; however ion thrusters, a class of plasma engines, are currently being used on missions to provide station-keeping duties or as the primary propulsion for spacecraft.

In other words: the age of plasma engines is already here!

What are the similarities between a fluorescent light and a typical plasma engine?

The biggest similarity is that both devices turn the gas that they contain into a conductor, so that current flows through it, and then use this to produce either light or a source of charged particles.

In a fluorescent light, the electrical circuit and the internal filaments turn the inert gas (usually Argon) into a plasma, which in turn heats mercury inside the tube so that it becomes a gas.
Once the mercury has become a gas it is excited by the moving electrons and emits light.
This light is mostly in the ultra-violet range and so is absorbed by a phosphor coating on the inside surface of the tube, which re-emits light in the visible range.

The light needs the plasma so that the mercury is evaporated; heating the mercury on its own would take more time and more power.

The fluorescent light can therefore stay cooler by creating the plasma than it can by just heating a filament on its own as in the case of the standard filament bulb, or by having to heat the mercury. In addition, it can run using less relative power than a standard bulb, which is why fluorescent bulbs are often used to provide bright light in larger rooms and spaces.

A typical plasma engine creates a plasma using a similar process. Electrons are introduced into a flowing inert gas, either Argon or Xenon, under the influence of either an electric field; both an electric and a magnetic field; or an electromagnetic wave in the radio or microwave frequency range. This produces the plasma, the quality of which is determined by lots of factors such as dimensions of the plasma chamber, amount of gas flow and applied power.

Once a plasma is created ions are extracted using electrical fields, often using grids or orifices that have been designed to produce an optimal ion beam for operation periods of more than 10,000 hours. Plasma creation and ion extraction occur concurrently with the ions being made neutral once they leave, by emitting electrons into the beam.

A plasma engine can only run efficiently by generating a source of ions in this way. Some other types of electric propulsion heat gas to increase its exhaust speed, hence increasing thrust, but they do not reach the same power efficiency or "specific impulse" that plasma engines can achieve using ions.

Plasma engines, then, are only suitable candidates for space missions because they utilise plasma for thrust.

Specific impulse, or the thrust per kilo weight (on Earth) of propellant over a time period of 1 second, is a quantity used frequently in space missions. Essentially, it relates to how much thrust can be produced by a device relative to the total mass of the fuel that can be carried on board a spacecraft.

High specific impulses are much preferred to lower specific impulses, as at times the cost of having more fuel for the mission can be the cost of having to upgrade to a bigger rocket.

You can see how both devices rely heavily on plasma in their design and that both types of device can be much more energy-efficient and useful only because they contain plasma.
Yet when you hear about plasma, plasma engines or plasma thrusters, the mind turns more to science fiction than to the light above your head in the kitchen.

Though it is true that only a handful of plasma engines are operational today compared to the ubiquity of fluorescent lights, the next time you look at that light in your kitchen or in your office, take a moment to reflect on how the glow that you can see is founded on the same process that is used to propel spacecraft to other planets.

If you need a fresh perspective consider this: the European Space Agency / Japanese Space Agency mission to the planet Mercury, called "BepiColombo", is using T6 ion thrusters, provided by QinetiQ, on its transfer module to get to the planet rather than using more conventional chemical thrusters. These ion thrusters use an internal circuit, that is different but not unrelated to the filaments in the fluorescent tube, where electrons are introduced into the gas to produce ions.

 
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