SDO
Full Name: Solar Dynamics Observatory
Phase: Development
Mission Project Home Page: http://sdo.gsfc.nasa.gov/
Program(s): Living With a Star
The Solar Dynamics Observatory (SDO) is the first mission to be launched for NASA's Living With a Star (LWS) Program, a program designed to understand the causes of solar variability and its impacts on Earth. SDO is designed to help us understand study the Sun's influence on Earth and Near-Earth space by studying observing the solar atmosphere on small scales of space and time and in many wavelengths simultaneously.
SDO's goal is to understand, driving towards a predictive capability, the solar variations that influence life on Earth and humanity's technological systems by determining how the Sun's magnetic field is generated and structured how this stored magnetic energy is converted and released into the heliosphere and geospace in the form of solar wind, energetic particles, and variations in the solar irradiance. SDO data will help us to understand the cause the how and why of the Sun's magnetic activity changes. It will determine how the magnetic field is generated and structured, and how the stored magnetic energy is released into the heliosphere and geospace. SDO data and analysis will also help us develop the ability to predict the solar activity variations. that influence life on Earth and humanity's technological systems.
SDO will observe different layers in solar atmosphere from visible surface, photosphere, to outer corona. measure the properties of the Sun and solar activity. There are few types of measurements but many of them will be taken. For example, Helioseismic and Magnetic Imager (HMI) will record maps of magnetic fields on entire visible solar hemisphere. HMI will also observe flows of plasma in the photosphere. These observations will be used to study motions throughout solar atmosphere: from the global scale (solar rotation), to small spatial scales (e.g. convective motions, which the surface velocity is measured by HMI. This data can be used for many different studies. One is the surface rotation rate, which must be removed to study the others. After subtracting the rotation, you have the oscillation and convective velocities. The latter look like billows of storm clouds covering the Sun. Hot gas moves outward at the center of the billows and downward at the edges—just like boiling water). Data from HMI will also allow us to study processes taking place underneath the visible surface. These studies will be conducted using methods of helioseismology, in the same manner as geologies on Earth study interior of our planet. Other SDO instruments, Atmospheric Imaging Assembly (AIA) will study hot outer layers of solar atmosphere, corona. AIA will take images and movies of corona in several wavelengths of ultraviolet light. The third SDO instrument, ), Extreme Ultraviolet Variability Experiment (EVE) will observe total every flux from the Sun, or irradiance. The variations in irradiance are important component of Earth's atmosphere and climate models.
SDO is scheduled to launch in October 2009.