I know it’s a bad idea, staring straight into the sun is terribly bad for your eyes. Thanks to NASA we have someone, or something, to do it for us and spare our eyes the trouble. The intent of NASA’s Living with a Star (LWS) Program is to understand the impacts of solar variability on Earth. It’s first mission is the Solar Dynamics Observatory (SDO), launched on February 11, 2010. Its goal is to understand solar variations that impact life on Earth and our technological systems. Eventually, NASA hopes to improve the prediction of solar variations by determining the structure of the Sun’s magnetic field and how it is generated.
Changes in solar irradiance can have a significant effect on Earth’s climate. Solar activity also has a decided impact on many of our instruments as solar flares and coronal mass ejections disrupt GPS communications, disable satellites and cause power grid failures. I don’t have to tell you that the Sun is extremely important to life on Earth and that ultraviolet radiation has a huge impact on its upper atmosphere. SDO’s Extreme Ultraviolet Variability Experiment (EVE) instrument measures fluctuations in the Sun’s extreme ultraviolet output.
Understanding the Sun’s physics is another priority of SDO. The Helioseismic and Magnetic Imager (HMI) maps the surface’s magnetic fields and is able to see below it. Data from the HMI is used to determine the interior mechanisms and sources of solar variability. In turn, this information leads to a better understanding of how surface activity and magnetic fields are affected by the Sun’s interior physical processes.
The Atmospheric Imaging Assembly (AIA) images the Sun’s atmosphere and surface in 10 different wavelengths. Four of the bands have never been used to monitor the solar corona and will open up new avenues of research and discovery. The AIA data of the coronal surface will be linked with changes in the Sun’s interior.
I’m sure you’re thinking, like I am, ‘Holy cow, that’s a LOT of data collection!’ We would be correct in this exclamation as SDO is constantly collecting data at a speed of one image every 0.75 seconds. Two radio antennas in Las Cruces, New Mexico are dedicated to collecting data from the satellite. Due to its geosynchronous orbit, the satellite is in constant view of the antennas so no data is lost. New data of the Sun streams to NASA every second and is made available for new discoveries and insights into Earth’s closest star.