SDO, the Solar Dynamics Observatory, was launched from Cape Canaveral on an Atlas 5 rocket on 2010 February 11 at 15:23 UT. SDO will observe the Sun from a 28.5 deg inclination geosynchronous orbit allowing continuous contact with a ground station at White Sands, NM.
SDO carries three instruments to study the Sun at high time and spatial resolution: the Helioseismic and Magnetic Imager (HMI), the Atmospheric Imaging Assembly (AIA), and the Extreme Ultraviolet Variability Experiment (EVE). HMI will use rapid-cadence magnetic field measurements to study the structure and dynamics of the solar interior and measure magnetic field directions to help determine when and where solar flares and coronal mass ejections are likely to occur. AIA is an array of four telescopes that will gather very high resolution images of the Sun every 10 s across eight wavelength bands. EVE will monitor variations in the Sun's extreme UV output. These emissions can disrupt satellite communications and navigation systems. Data from the SDO instruments will support the development of improved space weather forecast models.
SDO (Solar Dynamics Observatory) is the first in a series of missions in the Living With a Star program. The spacecraft is three-axis-stabilized, sun-pointing, in an inclined (28 degree) geosynchronous orbit. The mission's primary goal is to understand and, ideally, predict the solar variations that influence life on Earth and humanity's technological systems. SDO will do this by determining how the Sun's magnetic field is generated and structured and 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 brightness.
The spacecraft carries three instruments: the Atmospheric Imaging Assembly (AIA), the Extreme Ultraviolet Variability Experiment (EVE), and the Helioseismic and Magnetic Imager (HMI). AIA images the dynamic solar atmosphere in multiple wavelengths to link changes in the surface to those in the interior. EVE measures the solar extreme ultraviolet irradiance variations based on the sun's magnetic features. It helps scientists to understand the Sun's role in driving the outer atmosphere of Earth. HMI studies the origin of solar variability by characterizing and developing an understanding of the sun's interior and the various components of its magnetic activity. It extends the capabilities of the SOHO/MDI instrument to continuous full-disk coverage at higher spatial resolution and vector magnetograms.
The combined data rate is about 130 Mbit/s (150 Mbit/s with overhead, or 300 Msymbols/s with rate 1/2 convolutional encoding), and the craft will generate approximately 1.5 terabytes of data per day, beaming back 150 million bits of data every second or the equivalent of 380 full-length Hollywood movies. The prime mission is planned for five years, at the end of which the mission could be granted a five-year extension.
Alternate Names
SDO
Facts in Brief
Launch Date: 2010-02-11
Launch Vehicle: Atlas V
Launch Site: Cape Canaveral, United States
Mass: 270.0 kg
Nominal Power: 1540.0 W