A "Solar Prominence" from Soho

Caption NASA originale:"A 'Solar Prominence' is a cloud of solar gas held above the Sun's surface by the Sun's magnetic field. The Earth would easily fit under the hovering curtain of hot gas (like the one pictured above). A quiescent prominence typically lasts about one month, and may erupt in a Coronal Mass Ejection (CME) expelling hot gas into the Solar System. Although somehow related to the Sun's changing magnetic field, the energy mechanism that creates and sustains a Solar Prominence is still a mistery".