Two of the three instruments on Nasa’s solar dynamics observatory (SDO) are ready for launch on the spacecraft.

The 3,100kg SDO is an advanced spacecraft that will measure the interior of the sun, its magnetic field, hot plasma of the solar corona and the irradiance that creates the ionospheres of the planets.

The spacecraft will continually observe the sun to study solar activity and its impact on space weather using the three scientific instruments.

Two of the three are the Lockheed-built atmospheric imaging assembly (AIA), and the helioseismic and magnetic imager (HMI).

The AIA, a suite of four telescopes, will provide a view of the solar corona, taking images that span at least 1.3 solar diameters in multiple wavelengths simultaneously.

The HMI will study the origin of solar variability and try to characterise and understand the sun’s interior and magnetic activity.

HMI principal investigator Professor Philip Scherrer said the two instruments together would identify the possibility of predicting solar activity, based on which scientists would later evolve forecast methods.

The SDO lift-off is scheduled for 9 February 2010.