At the Sun's surface, sunspots are known to be dark planet-sized regions ofintense magnetic fields.But what lies below?Using observations from th MichelsonDoppler Imager (MDI) instrument aboard the space-base SOHOobservatory, astronomers have derive thispremier picture of the flowof material just beneath visible sunspot.The MDI data indicate that immediatel underthe sunspot a strong inflowing current exists, shown aboveby the dark arrows.This converging undertowpulls near-surface material toward the spot and preventsthe concentrated magnetic fields from flying apart,like repelling poles o ironmagnets.Such a configuration appears to divert the normal flo of plasmabubbling up from the solar interior, creating self-sustainingsunspot.The MDI instrument can explore the properties of the solar interiorby detecting motions produced b sound wavesas they interact at the solar surface.
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