Welcome to the CDS website

Launched in 1995, the ESA/NASA Solar and Heliospheric Observatory (SOHO) is the world's largest solar physics space mission and it has revolutionised our understanding of the Sun. The Coronal Diagnostic Spectrometer (CDS) is a unique instrument, designed to detect solar extreme ultraviolet radiation which allows us to probe conditions in the solar corona. The spectra recorded by CDS provide information on temperature, density, elemental composition and flows of very hot plasma trapped in the Sun's magnetic field. The CDS operation is run from RAL, where the requests for observations from a user community of 15 UK institutes and over 60 world-wide groups are coordinated, planned and run.

Latest News: Sun|trek - an educational resource for schools

Sun|trek is an exciting new website for school students and teachers about the Sun and its effect on the Earth. Sun|trek has been motivated and inspired by the fantastic images and movies of the Sun taken from space (for example from the SOHO satellite). It is narrated by solar guides (young solar researchers), who not only share the excitement that they feel about working with these solar space projects, but also say a bit about themselves, how they became interested in astronomy and what their other interests are. They are 'role models' who could inspire the younger students.

The detection of magneto-acoustic waves propagating from the chromosphere to the corona using CDS. Left panel: a composite CDS and TRACE multi-wavelength image of an active region. The coincidence of the sunspot umbra, sunspot plume (turquoise), and emerging coronal loop system (blue) is apparent. These are locations where magnetic-acoustic waves have been detected, propagating from the chromosphere to the corona. Right panel: atmospheric structure above a sunspot with increasing temperature, obtained from CDS and other SOHO instruments. More details can be found in Marsh & Walsh (2006).

SOHO Spacecraft animation QuickTime	Our mysterious Sun QuickTime	The complex & violent solar atmosphere QuickTime	The quiet and active Sun QuickTime
Close up on convection cells QuickTime	Peeling back the solar atmosphere QuickTime	Temperature mapping the Sun QuickTime	Solar Tornadoes.
The Vibrating Sun QuickTime	Coronal Mass Ejection QuickTime	Driving the Earths Aurora animation QuickTime	The Comet Neat QuickTime
Two out of a thousand Comets QuickTime	The big one QuickTime	Four Planets & the Plieades QuickTime	Magnetic Field Structure animation QuickTime

Surface Magnetic polarities QuickTime

Problems viewing the movies: Mozilla,Firefox & Windows Media Player should work fine together IE & Windows Media Player may have issues: Either click 'close' on the WMP 'download failed box' then click play on WMP (Once cached locally the movie should play) or right click on an image and select 'Save Target as' then save file to disc. Play the saved file by double clicking on it. or simply chose the QuickTime option

• 10,000,000 exposures have been taken
• 34,000 science studies have been run
• 240,000 science fits files have been produced
• 3,500 individual science plans have been made
• 400,000 command blocks have been sent to CDS by the CDS ground system
• 400GB of data sent back from CDS
• 666 reviewed science papers published
  The mechanisms have performed:
• 24,000,000 mirror steps
• 7,000,000 slit steps
• 24,000,000 instrument pointing movements
  and all with just one major service, and that was before launch