Science Current Events | Science News | Brightsurf.com
 

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


Therapeutically robust correction, in vitro, of the most common cystic fibrosis mutation
In experiments with isolated cystic fibrosis lung cells, University of Alabama at Birmingham researchers and colleagues from two other institutions have partially restored the lost function of those cells.

Harvard chemists develop simple new platform for development of macrolide antibiotics
Harvard researchers have created a new, greatly simplified, platform for antibiotic discovery that may go a long way to solving the crisis of antibiotic resistance.

A slick way to test artificial knees and hips
A new study suggests that natural proteins can be used to effectively test new replacement hip and knee joints in the laboratory.

36,000 children already tested for early type 1 diabetes
One year after the introduction of the Bavarian pilot project Fr1da, the Institute of Diabetes Research, Helmholtz Zentrum München has published the first results in the BMJ Open journal.

How repeated spot microdischarges damage microdevices
In microelectronics, devices made up of two electrodes separated by an insulating barrier are subject to multiple of microdischarges - referred to as microfilaments - at the same spot.

Under Pressure: New technique could make large, flexible solar panels more feasible
A new, high-pressure technique may allow the production of huge sheets of thin-film silicon semiconductors at low temperatures in simple reactors at a fraction of the size and cost of current technology.

Silk stabilizes blood samples for months at high temperatures
Researchers at Tufts University have stabilized blood samples for long periods of time without refrigeration and at high temperatures by encapsulating them in air-dried silk protein.

High blood pressure lowers significantly after drinking tart Montmorency cherry juice
Drinking tart Montmorency cherry juice significantly reduces high blood pressure at a level comparable to that achieved by medication, according to new research from Northumbria University, Newcastle.

Quantum chemical computations provide insight into liver toxicity
Balasubramanian and Basak have recently reported quantum chemical computations that enhance our understanding of mechanisms for the causes of liver toxicity.

Compound from hops lowers cholesterol, blood sugar and weight gain
A recent study at Oregon State University has identified specific intake levels of xanthohumol, a natural flavonoid found in hops, that significantly improved some of the underlying markers of metabolic syndrome in laboratory animals and also reduced weight gain.
More Plasma Current Events and Plasma News Articles

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 (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...

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 ß to 3%-5% in tokamaks at Oak Ridge and General Atomic; and the stabilization of mirror-confined plasmas at...

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...

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 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 and Fusion Plasma Electrodynamics

Plasma Physics and Fusion Plasma Electrodynamics
by Abraham Bers (Author)


Plasma is a ubiquitous state of matter at high temperatures. The electrodynamics of plasmas encompasses a large number of applications, from understanding plasmas in space and the stars, to their use in processing semiconductors, and their role in controlled energy generation by nuclear fusion. This book covers collective and single particle dynamics of plasmas for fully ionized as well as partially ionized plasmas. Many aspects of plasma physics in current fusion energy generation research are addressed both in magnetic and inertial confinement plasmas. Linear and nonlinear dynamics in hydrodynamic and kinetic descriptions are offered, making both simple and complex aspects of the subject available in nearly every chapter. The approach of dividing the basic aspects of plasma physics as...

Plasma Physics: An Introduction to Laboratory, Space, and Fusion Plasmas

Plasma Physics: An Introduction to Laboratory, Space, and Fusion Plasmas
by Alexander Piel (Author)


This book is an outgrowth of courses in plasma physics which I have taught at Kiel University for many years. During this time I have tried to convince my students that plasmas as different as gas dicharges, fusion plasmas and space plasmas can be described in a uni ed way by simple models. The challenge in teaching plasma physics is its apparent complexity. The wealth of plasma phenomena found in so diverse elds makes it quite different from atomic physics, where atomic structure, spectral lines and chemical binding can all be derived from a single equation―the Schrödinger equation. I positively accept the variety of plasmas and refrain from subdividing plasma physics into the traditional, but arti cially separated elds, of hot, cold and space plasmas. This is why I like to confront...

Plasma Etching: An Introduction (Plasma -- Materials Interactions)

Plasma Etching: An Introduction (Plasma -- Materials Interactions)
by Dennis M. Manos (Editor), Daniel L. Flamm (Editor)


Plasma etching plays an essential role in microelectronic circuit manufacturing. Suitable for researchers, process engineers, and graduate students, this book introduces the basic physics and chemistry of electrical discharges and relates them to plasma etching mechanisms. Throughout the volume the authors offer practical examples of process chemistry, equipment design, and production methods.

Platelet Rich Plasma in Musculoskeletal Practice

Platelet Rich Plasma in Musculoskeletal Practice
by Nicola Maffulli (Editor)


This book provides an introductory overview of advancements in platelet-rich plasma (PRP), focusing on current technologies and methods, new challenges and controversies, and avenues for further research. With many studies demonstrating a role for PRP in improving response to injury, this book aims to facilitate the application of this rapidly growing treatment option for trauma patients.  Platelet Rich Plasma in Musculoskeletal Practice is a highly informative and carefully presented book, providing  scientific and clinical insight for specialists who utilize PRP in daily practice, and for readers who are seeking to learn more about this effective injury treatment.  

© 2016 BrightSurf.com