Explanation: At the Sun's surface, sunspots are known to be dark, planet-sized regions of intense magnetic fields. But what lies below? Using observations from the Michelson Doppler Imager (MDI) instrument aboard the space-based SOHO observatory, astronomers have derived this premier picture of the flow of material just beneath a visible sunspot. The MDI data indicate that immediately under the sunspot a strong inflowing current exists, shown above by the dark arrows. This converging undertow pulls near-surface material toward the spot and prevents the concentrated magnetic fields from flying apart, like repelling poles of iron magnets. Such a configuration appears to divert the normal flow of plasma bubbling up from the solar interior, creating a self-sustaining sunspot. The MDI instrument can explore the properties of the solar interior by detecting motions produced by sound waves as they interact at the solar surface.
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NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: Sun - sunspot - magnetic field - mdi
Publications with words: Sun - sunspot - magnetic field - mdi
See also:
- APOD: 2024 September 2 Á A Triangular Prominence Hovers Over the Sun
- APOD: 2024 August 18 Á A Solar Prominence Eruption from SDO
- APOD: 2024 August 4 Á Gaia: Here Comes the Sun
- APOD: 2024 July 28 Á Sun Dance
- Prominences and Filaments on the Active Sun
- APOD: 2024 May 28 Á Solar X Flare as Famous Active Region Returns
- APOD: 2024 May 26 Á A Solar Filament Erupts