Solar experts detect waves in giant magnetic holes the size of the UK

February 24, 2011

Massive waves in giant magnetic holes on the surface of the Sun have been discovered for the first time by solar scientists from the University of Sheffield and Queen's University Belfast, something that will bring experts a step closer to unlocking the secrets of the Sun.

The Sun is interwoven by a complex network of magnetic field lines that are responsible for a large variety of fascinating features that can be seen in the solar atmosphere. Large, dark regions, which look like holes on the Sun's surface, mark out areas where the magnetic field breaks through from the Sun's deep, boiling interior and rises into the very hot solar atmosphere, which is over a million degrees. The largest of these dark regions are often called sunspots and have been studied since their discovery from as early as 364 BC.

Led by Professor Robertus von Fay-Siebenburgen, Head of the Solar Physics and Space Plasma Research Centre (SP2RC) at the University of Sheffield, the team studied a magnetic region of the Sun much smaller than a sunspot, however its size was still many times greater than the size of the UK.

Their research, which was published this week in Astrophysical Journal, has shown that the magnetic hole they observed, which is also known as a pore, is able to channel energy generated deep inside the Sun, along the magnetic field to the Sun's upper atmosphere. The magnetic field emerging through the pore is over 1,000 times stronger than the magnetic field of the Earth.

The energy being transported is in the form of a very special form of waves, known as 'sausage waves' which the scientists were able to observe using a UK-built solar imager known as ROSA (Rapid Oscillations of the Solar Atmosphere), which was designed by Queen's University Belfast and is in operation at the Dunn Solar Telescope, Sacramento Peak, USA. This is the first direct observation of 'sausage waves' at the solar surface. The magnetic hole is seen to increase and decrease in size periodically which is a characteristic feature of the 'sausage wave.'

The team of experts, including Dr Richard Morton from the University of Sheffield, as well as Professor Mihalis Mathioudakis and Dr David Jess from Queen's University Belfast, hope these giant magnetic holes will play an important role in unveiling the longstanding secrets behind solar coronal heating.

This is because the solar surface has a temperature of a few thousand degrees but the solar corona - the outermost, mysterious, and least understood layer of the Sun's atmosphere - is heated to temperatures often a thousand times hotter than the surface. Why the temperature of the Sun's atmosphere increases as we move further away from the centre of energy production, which lies under the surface, is a great mystery of astrophysics. The findings, which demonstrate the transfer of energy on a massive scale, offer a new explanation for this puzzle.

The team now hope to use further similar solar images from ROSA to understand the fine substructure of these massive magnetic holes by reconstructing the images to view what is inside the holes.

Professor Robertus von Fay-Siebenburgen, said: "This is a fascinating new discovery in line with a number of discoveries made in recent years by the team. It is the first time that 'sausage waves' have been detected in the Sun with such detail. Analysing these waves may bring us closer to understanding the physical mechanisms in the atmosphere of a star.

"I am very proud that such talented young researchers like Richard and Dave have shown such a serious commitment in bringing us closer to unveiling the secrets of the Sun. We're also very pleased that Professor Keenan and the Queen's University Belfast solar team were able to build such a wonderful instrument that allows us to make unprecedented observations with relatively low costs."

The news comes as part of the University of Sheffield's unique venture entitled Project Sunshine, led by the Faculty of Science. SP2RC plays a key role in Project Sunshine, which aims to unite scientists across the traditional boundaries in both the pure and applied sciences to harness the power of the Sun and tackle the biggest challenge facing the world today: meeting the increasing food and energy needs of the world´s population in the context of an uncertain climate and global environment change.
-end-
Notes to editors:

To view the research paper entitled 'Observations of Sausage Modes in Magnetic Pores' visit: http://iopscience.iop.org/2041-8205/729/2/L18

Project Sunshine, led by the Faculty of Science at the University of Sheffield aims to unite scientists across the traditional boundaries in both the pure and applied sciences to harness the power of the Sun and tackle the biggest challenge facing the world today: meeting the increasing food and energy needs of the world´s population in the context of an uncertain climate and global environment change. It is hoped that Project Sunshine will change the way scientists think and work and become the inspiration for a new generation of scientists focused on solving the world´s problems. The first international Project Sunshine conference, Shine, will take place from 13-14 September 2011 at Sheffield City Hall. For more information, visit: http://shine.sheffield.ac.uk/

For further information please contact: Shemina Davis, Media Relations Officer, on 0114 2225339 or email shemina.davis@sheffield.ac.uk

To view this news release and images online, visit http://www.shef.ac.uk/mediacentre/2011/1849-sun-waves-magnetic-solar.html

To read other news releases about the University of Sheffield, visit http://www.shef.ac.uk/mediacentre/

University of Sheffield

Related Magnetic Field Articles from Brightsurf:

Investigating optical activity under an external magnetic field
A new study published in EPJ B by Chengping Yin, Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, South China, aims to derive an analytical model of optical activity in black phosphorous under an external magnetic field.

Magnetic field and hydrogels could be used to grow new cartilage
Instead of using synthetic materials, Penn Medicine study shows magnets could be used to arrange cells to grow new tissues

Magnetic field with the edge!
This study overturns a dominant six-decade old notion that the giant magnetic field in a high intensity laser produced plasma evolves from the nanometre scale.

Global magnetic field of the solar corona measured for the first time
An international team led by Professor Tian Hui from Peking University has recently measured the global magnetic field of the solar corona for the first time.

Magnetic field of a spiral galaxy
A new image from the VLA dramatically reveals the extended magnetic field of a spiral galaxy seen edge-on from Earth.

How does Earth sustain its magnetic field?
Life as we know it could not exist without Earth's magnetic field and its ability to deflect dangerous ionizing particles.

Scholes finds novel magnetic field effect in diamagnetic molecules
The Princeton University Department of Chemistry publishes research this week proving that an applied magnetic field will interact with the electronic structure of weakly magnetic, or diamagnetic, molecules to induce a magnetic-field effect that, to their knowledge, has never before been documented.

Origins of Earth's magnetic field remain a mystery
The existence of a magnetic field beyond 3.5 billion years ago is still up for debate.

New research provides evidence of strong early magnetic field around Earth
New research from the University of Rochester provides evidence that the magnetic field that first formed around Earth was even stronger than scientists previously believed.

Massive photons in an artificial magnetic field
An international research collaboration from Poland, the UK and Russia has created a two-dimensional system -- a thin optical cavity filled with liquid crystal -- in which they trapped photons.

Read More: Magnetic Field News and Magnetic Field Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.