太阳光谱：升落与空间天气

HMI (Helioseismic and Magnetic Imager) magnetogram photos depict the sun's magnetic field strength and direction on its surface. These images, taken by the HMI instrument on the Solar Dynamics Observatory (SDO) satellite, reveal the intricate magnetic structures, including sunspots and active regions.

HMI intensitygram photos display the sun's surface in visible light, highlighting features such as sunspots, granulation, and solar faculae. These images, captured by the HMI instrument aboard the Solar Dynamics Observatory (SDO), provide a detailed view of the sun's photosphere, allowing for the observation of sunspot development and movement.

These photos capture the sun in the 171 angstrom wavelength, highlighting the solar corona and upper transition region. These images, taken by the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO), reveal the structure of the sun's outer atmosphere and trace the magnetic field lines extending into space. The 171 Å wavelength is particularly effective at showing the million-degree plasma loops that emerge from the sun's surface.

AIA 193 Å photos capture the sun in the 193 angstrom wavelength, focusing on both the hot corona and the cooler material of solar flares and coronal mass ejections (CMEs). These images reveal the sun's outer atmosphere and coronal holes, which are regions where the solar wind escapes into space. The 193 Å wavelength is particularly useful for observing the high-temperature plasma that forms in the corona, typically around 1.25 million Kelvin, and during solar flares, it can reach up to 20 million Kelvin.