Science Current Events | Science News |

Researchers create 'MRI' of the sun's interior motions

July 09, 2012

A team of scientists has created an "MRI" of the Sun's interior plasma motions, shedding light on how it transfers heat from its deep interior to its surface. The result, which appears in the journal the Proceedings of the National Academy of Sciences, upends our understanding of how heat is transported outwards by the Sun and challenges existing explanations of the formation of sunspots and magnetic field generation.

The work was conducted by researchers from NYU's Courant Institute of Mathematical Sciences and its Department of Physics, Princeton University, the Max Planck Institute, and NASA.

The Sun's heat, generated by nuclear fusion in its core, is transported to the surface by convection in the outer third. However, our understanding of this process is largely theoretical-the Sun is opaque, so convection cannot be directly observed. As a result, theories largely rest on what we know about fluid flow and then applying them to the Sun, which is primarily composed of hydrogen, helium, and plasma.

Developing a more precise grasp of convection is vital to comprehending a range of phenomena, including the formation of sunspots, which have a lower temperature than the rest of the Sun's surface, and the Sun's magnetic field, which is created by its interior plasma motions.

In order to develop their "MRI" of the Sun's plasma flows, the researchers examined high-resolution images of the Sun's surface taken by the Helioseismic and Magnetic Imager (HMI) onboard NASA's Solar Dynamics Observatory. Using a 16-million pixel camera, HMI measures motions on the Sun's surface caused by convection.

Once the scientists captured the precise movement waves on the Sun's surface, they were able to calculate its unseen plasma motions. This procedure is not unlike measuring the strength and direction of an ocean's current by monitoring the time it takes a swimmer to move across the water-currents moving against the swimmer will result in slower times while those going in the same direction will produce faster times, with stronger and weaker currents enhancing or diminishing the impact on the swimmer.

What they found significantly departed from existing theory--specifically, the speed of the Sun's plasma motions were approximately 100 times slower than scientists had previously projected.

"Our current theoretical understanding of magnetic field generation in the Sun relies on these motions being of a certain magnitude," explained Shravan Hanasoge, an associate research scholar in geosciences at Princeton University and a visiting scholar at NYU's Courant Institute of Mathematical Sciences. "These convective motions are currently believed to prop up large-scale circulations in the outer third of the Sun that generate magnetic fields."

"However, our results suggest that convective motions in the Sun are nearly 100 times smaller than these current theoretical expectations," continued Hanasoge, also a postdoctoral fellow at the Max Plank Institute in Katlenburg-Lindau, Germany. "If these motions are indeed that slow in the Sun, then the most widely accepted theory concerning the generation of solar magnetic field is broken, leaving us with no compelling theory to explain its generation of magnetic fields and the need to overhaul our understanding of the physics of the Sun's interior."


The study's other co-authors were Thomas Duvall, an astrophysicist at NASA, and Katepalli Sreenivasan, University Professor in NYU's Department of Physics and Courant Institute. Sreenivasan is also Senior Vice Provost for Science and Technology for the Global Network University at NYU and Provost of Polytechnic Institute of NYU.

New York University

Related Plasma Current Events and Plasma News Articles

The mechanism of maintaining cell polarity visualized by super-resolution microscope
Cells are not uniform spheres; they generally come in a variety of disparate shapes. In the broadest sense, this variation in shapes is known as cell polarity, and it is an essential property for a variety of cell functions.

New target, potential treatment found for unhealthy levels of fat that can occur in type 1 diabetes
Researchers have new insight into the complex interchange that can raise blood levels of unhealthy lipids, or fat, in type 1 diabetes, and early evidence that a drug under study to block cancer cell growth can restore healthier levels.

A disposable, highly sensitive biosensing system
We are pleased to announce that a new biosensing platform has been fabricated for the determination of Haptoglobin in human blood.

Evidence of a lipid link in the inherited form of Alzheimer's disease
Australian researchers have found biochemical changes occurring in the blood, in the rare inherited form of Alzheimer's disease.

Research shows weight loss and improved cholesterol levels with walnut-rich diet
A new study published in the Journal of the American Heart Association found that a diet containing unsaturated fats, such as those found in walnuts and olive oil, has similar weight loss effects as a lower fat, higher-carbohydrate diet.

Emergency blood transfusions for major trauma need to be more rapid and consistent
Only two per cent of patients with life-threatening bleeding after serious injury receive optimal blood transfusion therapy in England and Wales, according to research led by Queen Mary University of London (QMUL) and NHS Blood and Transplant.

Icy ebb and flow influenced by hydrothermal activity
The last million years of Earth's history was dominated by the cyclic advance and retreat of ice sheets over large swaths of North America. During cold glacial intervals, ice sheets reached as far south as Long Island and Indiana, while during warm interglacial periods the ice rapidly retreated to Greenland.

Self-stacking nanogrids
Since the 1960s, computer chips have been built using a process called photolithography. But in the past five years, chip features have gotten smaller than the wavelength of light, which has required some ingenious modifications of photolithographic processes.

Plasma marker of vascular disease confirmed in type 1 diabetes patients
In an article published ahead of print on November 24, 2015 in the journal Diabetes (available at, researchers from the Medical University of South Carolina (MUSC), the American University of Beirut (AUB), and Case Western Reserve University report that a molecule called pre-kallikrein (PK) could be a target for the vascular complications associated with type 1 diabetes.

E-cigarettes deliver sufficient nicotine to suppress smoking desire and reduce tobacco withdrawal symptoms in smokers, comparable to Nicorette
A new study, published in the Journal of Regulatory Toxicology and Pharmacology, found that e-cigarettes share a similar short-term safety profile as Nicorette® products and are comparable in reducing tobacco withdrawal symptoms.
More Plasma Current Events and Plasma News Articles

Introduction to plasma physics and controlled fusion. Volume 1, Plasma physics

Introduction to plasma physics and controlled fusion. Volume 1, Plasma physics
by Francis F. Chen (Author)

TO THE SECOND EDITION In the nine years since this book was first written, rapid progress has been made scientifically in nuclear fusion, space physics, and nonlinear plasma theory. At the same time, the energy shortage on the one hand and the exploration of Jupiter and Saturn on the other have increased the national awareness of the important applications of plasma physics to energy production and to the understanding of our space environment. In magnetic confinement fusion, this period has seen the attainment 13 of a Lawson number nTE of 2 x 10 cm -3 sec in the Alcator tokamaks at MIT; neutral-beam heating of the PL T tokamak at Princeton to KTi = 6. 5 keV; increase of average Ăź to 3%-5% in tokamaks at Oak Ridge and General Atomic; and the stabilization of mirror-confined plasmas at...

Plasma Engineering: Applications from Aerospace to Bio and Nanotechnology

Plasma Engineering: Applications from Aerospace to Bio and Nanotechnology
by Michael Keidar (Author), Isak Beilis (Author)

Plasma engineering applies the unique properties of plasmas (ionized gases) to improve processes and performance over many fields, such as materials processing, spacecraft propulsion, and nanofabrication. Plasma Engineering considers this rapidly expanding discipline from a unified standpoint, addressing fundamentals of physics and modeling as well as new real-word applications in aerospace, nanotechnology, and bioengineering. The book starts by reviewing plasma particle collisions, waves, and instabilities, and proceeds to diagnostic tools, such as planar, spherical, and emissive probes, and the electrostatic analyzer, interferometric technique, and plasma spectroscopy. The physics of different types of electrical discharges are considered, including the classical Townsend mechanism of...

Plasma Physics: An Introduction

Plasma Physics: An Introduction
by Richard Fitzpatrick (Author)

Encompasses the Lectured Works of a Renowned Expert in the Field Plasma Physics: An Introduction is based on a series of university course lectures by a leading name in the field, and thoroughly covers the physics of the fourth state of matter. This book looks at non-relativistic, fully ionized, nondegenerate, quasi-neutral, and weakly coupled plasma. Intended for the student market, the text provides a concise and cohesive introduction to plasma physics theory, and offers a solid foundation for students wishing to take higher level courses in plasma physics. Mathematically Rigorous, but Driven by Physics This work contains over 80 exercises―carefully selected for their pedagogical value―with fully worked out solutions available in a separate solutions manual for professors. The...

Plasma Physics and Engineering, Second Edition

Plasma Physics and Engineering, Second Edition
by Alexander Fridman (Author), Lawrence A. Kennedy (Author)

Plasma plays an important role in a wide variety of industrial processes, including material processing, environmental control, electronic chip manufacturing, light sources, and green energy, not to mention fuel conversion and hydrogen production, biomedicine, flow control, catalysis, and space propulsion. Following the general outline of the bestselling first edition, Plasma Physics and Engineering, Second Edition provides a clear fundamental introduction to all aspects of the modern field. Reflecting recent scientific and technological developments, this resource will be useful to engineers, scientists, and students working with the physics, engineering, chemistry, and combustion of plasma, as well as chemical physics, lasers, electronics, new methods of material treatment, fuel...

Principles of Plasma Discharges and Materials Processing , 2nd Edition

Principles of Plasma Discharges and Materials Processing , 2nd Edition
by Michael A. Lieberman (Author), Alan J. Lichtenberg (Author)

A Thorough Update of the Industry Classic on Principles of Plasma Processing

The first edition of Principles of Plasma Discharges and Materials Processing, published over a decade ago, was lauded for its complete treatment of both basic plasma physics and industrial plasma processing, quickly becoming the primary reference for students and professionals.

The Second Edition has been carefully updated and revised to reflect recent developments in the field and to further clarify the presentation of basic principles. Along with in-depth coverage of the fundamentals of plasma physics and chemistry, the authors apply basic theory to plasma discharges, including calculations of plasma parameters and the scaling of plasma parameters with control parameters.


Plasma Physics (Dover Books on Physics)

Plasma Physics (Dover Books on Physics)
by James E. Drummond (Author)

A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and '70s.
Hailed by Science magazine as a "well executed venture," the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwave plasma physics. Highlights include Klimontovich's article on quantum plasmas, Buneman's writings on how to distinguish between attenuating and amplifying waves, and Yoler's clear and cogent...

Plasma Chemistry

Plasma Chemistry
by Alexander Fridman (Author)

This unique book provides a fundamental introduction to all aspects of modern plasma chemistry. The book describes mechanisms and kinetics of chemical processes in plasma, plasma statistics, thermodynamics, fluid mechanics, and electrodynamics, as well as all major electric discharges applied in plasma chemistry. The book considers most of the major applications of plasma chemistry from electronics to thermal coatings, from treatment of polymers to fuel conversion and hydrogen production, and from plasma metallurgy to plasma medicine. The book can be helpful to engineers, scientists, and students interested in plasma physics, plasma chemistry, plasma engineering, and combustion, as well as in chemical physics, lasers, energy systems, and environmental control. The book contains an...

Plasma Physics via Computer Simulation (Series in Plasma Physics)

Plasma Physics via Computer Simulation (Series in Plasma Physics)
by C.K. Birdsall (Author), A.B Langdon (Author)

Divided into three main parts, the book guides the reader to an understanding of the basic concepts in this fascinating field of research. Part 1 introduces you to the fundamental concepts of simulation. It examines one-dimensional electrostatic codes and electromagnetic codes, and describes the numerical methods and analysis. Part 2 explores the mathematics and physics behind the algorithms used in Part 1. In Part 3, the authors address some of the more complicated simulations in two and three dimensions. The book introduces projects to encourage practical work Readers can download plasma modeling and simulation software ― the ES1 program ― with implementations for PCs and Unix systems along with the original FORTRAN source code. Now available in paperback, Plasma Physics via...

Plasma Physics and Fusion Energy

Plasma Physics and Fusion Energy
by Jeffrey P. Freidberg (Author)

Considering the worldwide increase of interest in fusion research over the last decade - the recognition that a large number of new, environmentally attractive, sustainable energy sources will be needed to meet ever-increasing demands for electrical energy, is obvious. This book serves up the latest interest in alternative energy. Based on a series of graduate course notes in plasma physics and fusion energy at MIT, the text begins with an overview of world energy needs, current methods of energy generation, and the potential role that fusion may play in the future. It covers energy issues such as the production of fusion power, power balance, the design of a simple fusion reactor, and the basic plasma physics issues faced by the developers of fusion power. This book is suitable for...

Plasma Physics for Astrophysics (Princeton Series in Astrophysics (Paperback))

Plasma Physics for Astrophysics (Princeton Series in Astrophysics (Paperback))
by Russell M. Kulsrud (Author)

In this book, a distinguished expert introduces plasma physics from the ground up, presenting it as a comprehensible field that can be grasped largely on the basis of physical intuition and qualitative reasoning, similar to other fields of physics. Plasmas are ionized gases that can be found in a hydrogen bomb explosion, the confinement chamber of an experimental fusion reactor, the solar corona, the aurora borealis, the interstellar medium, and the immediate vicinity of a gravitational black hole. Not surprisingly, plasma physics appears to consist of numerous topics arising independently from astrophysics, fusion physics, and other practical applications, and hence it remains a field poorly understood even by many astrophysicists. But, in fact, most of these topics can be...

© 2016