Details of UK involvement in upcoming mission to study the Sun will be
outlined at the RAS National Astronomy Meeting in Birmingham on Thursday 7th
April. Dr Lidia van Driel-Gesztelyi of UCL’s Mullard Space Science
Laboratory will make a presentation on NASA’s Solar Dynamic Observatory
mission, which is due for launch in 2008.

The Solar Dynamics Observatory (SDO) will carry helioseismic instrumentation
to study oscillations caused by sound waves trapped in the solar interior
and sensors to measure the strength and direction of magnetic field at the
Sun’s surface. The spacecraft will also make high-resolution images of the
solar atmosphere at ten separate Extreme Ultra Violet (EUV) wavelengths and
measure the absolute radiation output of the Sun in the EUV spectral range.

The UK is playing a major role in this international solar mission. A
consortium of British scientists is developing eSDO, a project designed to
give the UK solar-terrestrial physics community easy access to the data
received from the spacecraft. The data volume received on the ground from
SDO will amount to around two million million bytes each day – equivalent to
3000 CDs. The UK team must provide scientists with effective access to this
enormous data volume. They will write specialist computer programmes for the
efficient analysis of the helioseismology, magnetic field and atmospheric
imaging data, and will develop data-summary formats to allow high-speed
browsing for particular phenomena in the SDO databases. The team will also
enable distributed processing and storage of the SDO data using the
architecture developed by the UK AstroGrid project. This requires
Grid-compatible software and must ensure access to appropriate data centres
in both the US and the UK.

In addition to the data related activities, the cameras for the SDO imaging
instruments are being developed under a NASA contract at CCLRC Rutherford
Appleton Laboratory, using CCDs produced by the E2V company.

SDO will continue work started by the joint NASA-ESA mission, SOHO, which
was launched in late 1995. Technological advances mean that the SDO
spacecraft can observe the full Sun continuously with 1 arc sec resolution
and will have a data rate approximately ten thousand times greater than that
available to SOHO. As Prof Len Culhane, the Principal Investigator for eSDO
explains, “Following the outstanding success of SOHO, the SDO mission will
provide the next major advances in heleioseismology and will for the first
time allow the connection between the Sun’s interior and its outer
atmosphere to be directly examined”.

SDO is the first mission in NASA’s new research programme, “Living with a
Star”, which aims to clarify the Sun’s role in influencing the near-Earth
environment and the Earth’s climate. To understand the impact of the Sun on
the near-Earth environment in particular, it is first necessary to
understand the Sun itself. Forecasting the occurrence and magnetic
configuration of Coronal Mass Ejections (CMEs) would allow us to protect
communications and other spacecraft in near-Earth orbits from their damaging
effects. Plasma streams, with a mass of approximately ten thousand billion
kilograms, arrive at Earth some 40 hours after a CME is launched from the
Sun. When the plasma interacts with the Earth’s magnetic field, it produces
accelerated particles that can cause electronic failures in satellites and
airplanes, immediate and long-term hazards to astronauts as well as aircraft
crews.

SDO will give us a more complete picture of the generation of magnetic
fields in the Sun’s interior, their emergence through the solar surface and
their interaction with the high temperature plasma that exists in the solar
atmosphere or corona.

NOTES FOR EDITORS

The 2005 RAS National Astronomy Meeting is hosted by the University of
Birmingham, and sponsored by the Royal Astronomical and the UK Particle
Physics and Astronomy Research Council (PPARC).

RAS NAM 2005 website: http://www.sr.bham.ac.uk/nam2005/index.html

eSDO

The eSDO project is funded by Particle Physics and Astronomy Research
Council to provide the solar community access to data and specialist
processing algorithms for the Solar Dynamic Observatory. The eSDO project is
run by a consortium UCL’s Mullard Space Science Laboratory, CCLRC Rutherford
Appleton Laboratory, the University of Birmingham and the University of
Sheffield.

CONTACTS

From Tuesday 5th April – Friday 8th April, Dr van Driel-Gesztelyi can be
contacted via the RAS NAM press office (see above).

Dr. Lidia van Driel-Gesztelyi
Solar & Stellar Physics Group
Mullard Space Science Lab
E-mail: lvdg@mssl.ucl.ac.uk
E-mail: Lidia.vanDriel@obspm.fr
Tel: +33 (0)1-45077900

Prof. Len Culhane,
Solar & Stellar Physics Group
Mullard Space Science Laboratory
University College London
Holmbury St Mary, Dorking, RH5 6NT, UK
Tel: +44 (0)1483 204139
E-mail: jlc@mssl.ucl.ac.uk

FURTHER INFORMATION

eSDO homepage: http://www.mssl.ucl.ac.uk/twiki/bin/view/SDO/WebHome

SDO homepage: http://sdo.gsfc.nasa.gov/