Solar Observation Satellites - SDO and SOHO

The Solar Dynamics Observatory (SDO)

SDO Satellite
SDO is a NASA mission to make detailed observations of  the Sun.  SDO was launched on February 11, 2010.  SDO's goal is to understand the Sun's influence on Earth and near-Earth space by studying the solar atmosphere on small scales of space and time and in many wavelengths simultaneously. SDO will investigate 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.


Magnetic Field LinesMain Scientific Objectives:

SDO is a 5-year mission that will determine how the sun’s magnetic field is generated, structured, and converted into violent solar events like turbulent solar wind, solar flares, and Coronal Mass Ejections (CMEs).  The solar wind is a continuous stream of electrically charged particles that flow from the sun and fill the solar system with charged particles and magnetic fields.  Solar flares are explosions in the sun’s atmosphere, with the largest equal to billions of one-megaton nuclear bombs.  CMEs are eruptions from the solar atmosphere that release billions of tons of solar material into interplanetary space at millions of miles per hour.  All these phenomena are collectively called space weather.  By improving our understanding of the solar activity that powers severe space weather, SDO will enable us to improve predictions of solar storms and provide information necessary to protect our technological systems.



The Solar and Heliospheric Observatory (SOHO)

SOHO Satellite

SOHO is a spacecraft built by a European industrial consortium and launched in 1995 to study the Sun.  During this time it has discovered over 2200 comets.  It began normal operations in early 1996 as a joint project of international cooperation between the European Space Agency (ESA) and NASA. SOHO is currently the main source of near-real time solar data for space weather prediction. 

SOHO is one of three spacecraft currently in the vicinity of the Earth-Sun L1 point, a unique point of gravitational balance located approximately 0.99 astronomical unit (AU)s from the Sun and 0.01 AU from the Earth.





Coronal Mass Ejection


Main Scientific Objectives: