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Graphic representing the various Heliophysics disciplines; Sun, Earth, Space Weather, Near-Earth Space and the Magnetosphere.
Science Mission Directorate:

Understanding the Sun, Heliosphere, and Planetary Environments as a single connected system is a goal of the Heliophysics Research Program.

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How SDO Sees the Sun

    The Solar Dynamics Observatory (SDO) provides views of the Sun in detail never before possible. Launched on February 11, 2010, SDO provides ultra high-definition imagery of the Sun in 13 different wavelengths, utilizing two imaging instruments, the Atmospheric Imaging Assembly (AIA) instrument and the Helioseismic and Magnetic Imager (HMI). Each wavelength is based on one or two types of ions -- though slightly longer and shorter wavelengths produced by other ions are also part of the picture. Each wavelength was chosen to highlight a particular part of the sun's atmosphere, from the solar surface to the upper reaches of the sun's corona.

    For more technical information about which ions produce which wavelengths, click on each globe of SDO images to link down to the descriptions. NOTE: If the

    SDO views the sun in 13 different ways, using two different instruments The HMI dopplergram provides maps of velocity on the sun's surface. HMI Magnetograms show maps of the magnetic field on the sun's surface, with black showing magnetic field lines pointing away from Earth, and white showing magnetic field lines coming toward Earth. The HMI Continuum provides photographs of the solar surface, incorporating a broad range of visible light. The AIA 1700 channel records ultraviolet light continuum and shows the surface of the sun. As well as a layer of the sun's atmosphere called the chromosphere, which lies just above the photosphere and is where the temperature begins rising. The AIA 4500 records the white light continuum and shows the sun's surface or photosphere. The AIA 1600 channel is emitted by carbon-4 (C IV) at around 10,000 Kelvin. C IV at these temperatures is present in the upper photosphere and what's called the transition region, a region between the chromosphere and the upper most layer of the sun's atmosphere called the corona. The transition region is where the temperature rapidly rises. SDO images of this wavelength are typically colorized in dark yellow. The AIA 304 channel is emitted by helium-2 (He II) at around 50,000 Kelvin. This light is emitted from the chromosphere and transition region. SDO images of this wavelength are typically colorized in red. The AIA 171 channel is emitted by iron-9 (Fe IX) at around 600,000 Kelvin. This wavelength shows the quiet corona and coronal loops and is typically colorized in gold. The AIA 193 channel is emitted by iron-12 (Fe XII) at 1,000,000 Kelvin and iron 24 (Fe XXIV) at 20,000,000 Kelvin. The former represents a slightly hotter region of the corona and the later represents the much hotter material of a solar flare. This wavelength is typically colorized in light brown. The AIA 211 channel is emitted by iron-14 (Fe XIV) at temperatures of 2,000,000 Kelvin. These images show hotter, magnetically active regions in the sun's corona and are typically colorized in purple. The AIA 335 channel is emitted by iron-16 (Fe XVI) at temperatures of 2,500,000 Kelvin. These images also show hotter, magnetically active regions in the corona, and are typically colorized in blue. The AIA 94 channel is emitted by iron-18 (Fe XVIII) at temperatures of 6,000,000 Kelvin. Temperatures like this represent regions of the corona during a solar flare. The images are typically colorized in green. The AIA 131 channel is emitted by iron-20 (Fe XX) and iron-23 (Fe XXIII) at temperatures greater than 10,000,000 Kelvin, representing the material in flares. The images are typically colorized in teal.
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    Each of the wavelengths observed by NASA's Solar Dynamics Observatory (SDO) was chosen to emphasize a specific aspect of the sun's surface or atmosphere. This image shows imagery both from the Advanced Imaging Assembly (AIA), which helps scientists observe how solar material moves around the sun's atmosphere, and the Helioseismic and Magnetic Imager (HMI), which focuses on the movement and magnetic properties of the sun's surface. More details for each wavelength and links to real-time SDO imagery follows.Credit: NASA/SDO/GSFC

    NOTE: If the real-time images below right appear black, the satellite data feed is temporarily unavailable. Please check back later.

    HMI Dopplergram, Surface movement
    HMI Dopplergram

    Dopplergrams provide maps of velocity on the sun's surface. Solar Region: Photosphere
    › View real-time HMI Dopplergram

    HMI Magnetogram, Magnetic field polarity HMI Magnetogram

    Magnetograms show maps of the magnetic field on the sun’s surface, with black showing magnetic field lines pointing away from Earth, and white showing magnetic field lines coming toward Earth. Solar Region: Photosphere
    › View real-time HMI Magnetogram

    HMI Continuum, Matches visible light HMI Continuum

    Continuums provide photographs of the solar surface, incorporating a broad range of visible light. Solar Region: Photosphere
    › View real-time HMI Continuum

    AIA 1700 AIA 1700

    Ultraviolet light continuum, shows the surface of the sun. As well as a layer of the sun's atmosphere called the chromosphere, which lies just above the photosphere and is where the temperature begins rising. Temperatures: 4500 Kelvin, Solar Region: Photosphere/Chromosphere
    › View real-time AIA 1700

    AIA 4500 AIA 4500

    White light continuum showing the sun's surface or photosphere. Temperatures: 6000 Kelvin, Solar Region: Photosphere
    › View real-time AIA 4500

    AIA 1600 AIA 1600

    Emitted by carbon-4 (C IV) at around 10,000 Kelvin. C IV at these temperatures is present in the upper photosphere and what's called the transition region, a region between the chromosphere and the upper most layer of the sun's atmosphere called the corona. The transition region is where the temperature rapidly rises. SDO images of this wavelength are typically colorized in dark yellow. Solar Region: Upper Photosphere/Transition Region
    › View real-time AIA 1600

    AIA 304 AIA 304

    Emitted by helium-2 (He II) at around 50,000 Kelvin. This light is emitted from the chromosphere and transition region. SDO images of this wavelength are typically colorized in red. Solar Region: Transition Region/Chromasphere
    › View real-time AIA 304

    AIA 171 AIA 171

    Emitted by iron-9 (Fe IX) at around 600,000 Kelvin. This wavelength shows the quiet corona and coronal loops, and is typically colorized in gold. Solar Region: Upper Transition Region/Quiet Corona
    › View real-time AIA 171

    AIA 193 AIA 193

    Emitted by iron-12 (Fe XII) at 1,000,000 K and iron 24 (Fe XXIV) at 20,000,000 Kelvin. The former represents a slightly hotter region of the corona and the later represents the much hotter material of a solar flare. This wavelength is typically colorized in light brown. Solar Region: Corona/Flare Plasma
    › View real-time AIA 193

    AIA 211 AIA 211

    Emitted by iron-14 (Fe XIV) at temperatures of 2,000,000 Kelvin. These images show hotter, magnetically active regions in the sun's corona and are typically colorized in purple. Solar Region: Active Regions
    › View real-time AIA 211

    AIA 335 AIA 335

    Emitted by iron-16 (Fe XVI) at temperatures of 2,500,000 Kelvin. These images also show hotter, magnetically active regions in the corona, and are typically colorized in blue. Solar Region: Active Regions
    › View real-time AIA 335

    AIA 335 AIA 094

    Emitted by iron-18 (Fe XVIII) at temperatures of 6,000,000 Kelvin. Temperatures like this represent regions of the corona during a solar flare. The images are typically colorized in green. Solar Region: Flaring Regions
    › View real-time AIA 094

    AIA 131 AIA 131

    Emitted by iron-20 (Fe XX) and iron-23 (Fe XXIII) at temperatures greater than 10,000,000 Kelvin, representing the material in flares. The images are typically colorized in teal. Solar Region: Flaring Regions
    › View real-time AIA 131

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