Giant pipe organ in the solar atmosphere (Forwarded)

Royal Astronomical Society
London, U.K.

Issued by RAS Press Officers:

Robert Massey
Tel: +44 (0)20 7734 4582
AND
Anita Heward
Tel: +44 (0)1483 420 904

NATIONAL ASTRONOMY MEETING PRESS ROOM (16 - 20 APRIL ONLY):
Tel: +44 (0)1772 892 613
+44 (0)1772 892 475
+44 (0)1772 892 477

RAS Web site:
http://www.ras.org.uk/

RAS National Astronomy Meeting web site:
http://nam2007.uclan.ac.uk

CONTACT:

Professor Robert von Fay-Siebenburgen
Head of SP2RC
Solar Physics and Space Plasma Research Centre
University of Sheffield
Tel: +44 (0)114 222 3832

From 16 to 20 April, Professor von Fay-Siebenburgen or Dr Taroyan can be
contacted via the NAM press office (see above).

PRESS INFORMATION NOTE: RAS PN 07/28 (NAM 24)

EMBARGOED FOR 00:01 BST, THURSDAY 19 APRIL 2007

GIANT PIPE ORGAN IN THE SOLAR ATMOSPHERE

Astronomers have found that the atmosphere of the Sun plays a kind of
heavenly music. The magnetic field in the outer regions (the corona) of
our nearest star forms loops that carry waves and behave rather like a
musical instrument. In a talk on Thursday 19 April at the Royal
Astronomical Society National Astronomy Meeting in Preston, Dr Youra
Taroyan and Professor Robert von Fay-Siebenburgen of the Solar Physics and
Space Plasma Research Centre (SP2RC), University of Sheffield will explain
the origin of these magnetic sound waves. They will present a series of
animations and sound files that demonstrate how these dramatic events
appear and fade away rapidly.

In recent years scientists have worked hard to better explain and predict
the dynamic behaviour of the Sun. For example, missions like STEREO and
Hinode watch as material is ejected towards the Earth, events which are
controlled by the solar magnetic field.

In their research, led by Professor von Fay-Siebenburgen, SP2RC scientists
combined observations with new theoretical models to study the magnetic
sound waves that are set up along loops in the corona. "These loops can be
up to 100 million kilometres long and guide waves and oscillations in a
similar way to a pipe organ," says Dr Taroyan

The acoustic waves can be extremely powerful and reach amplitudes of tens
of kilometres per second. Professor von Fay-Siebenburgen adds, "we found
that the waves are often generated at the base of the magnetic pipes by
enormous explosions known as micro-flares. These release energy equivalent
to millions of hydrogen bombs. After each micro-flare, sound booms are
rapidly excited inside the magnetic pipes before decaying in less than an
hour and dissipating in the very hot solar corona."

NOTES FOR EDITORS

The 2007 RAS National Astronomy Meeting is hosted by the University of
Central Lancashire. It is sponsored by the Royal Astronomical Society and
the UK Science and Technology Facilities Council.

This year the NAM is being held together with the UK Solar Physics (UKSP)
and Magnetosphere, Ionosphere and Solar-Terrestrial (MIST) spring
meetings. 2007 is International Heliophysical Year.

IMAGES:

Images, animations and sound files can be found at
http://www.robertus.staff.shef.ac.uk.../uksp-nam2007/