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Crystal (LM) Hi, If a solar flare shoots material into space from the sun's surface, where then does the term "coronal" mass ejection come into play, isn't the corona a part of the atmosphere, and not the surface? thank you

Hi Crystal,

These are very good questions and I hope another scientist can help answer your question as well. But I'll take a first shot.

Yes, the Corona is part of the atmosphere.  And solar flares do shoot material from the sun's "surface" into space - some plasma and magnetic fields. I think maybe the confusion is that solar flares are not coronal mass ejections. Scientists are still trying to understand how solar flares and coronal mass ejections are related, so if you decide to study solar physics for a career, you could make some discoveries about these phenomena. Your confusion is due in part because there is still a lot to learn about these two phenomena.

The simplified answer about the difference between Coronal Mass Ejections (CMEs) and solar flares is that CMEs do eject large amounts of mass from the corona whereas most of the "stuff" coming from solar flares is actually light (in different wavelengths, like x-rays). These x-rays come from a region just above the surface, so not quite from the surface proper. But the magnetic fields involved in both CMEs and solar flares are tied to the Sun's surface and these magnetic fields seem to be what make CMEs and solar flares somewhat similar.

Laura

Hi Crystal, In fact the name “coronal mass ejection” is considered misleading! The word ‘coronal’ was chosen in the first place because coronal mass ejections (or shortly CMEs) are observed with a device called coronagraph: Coronagraph creates an artificial solar eclipse. When the Sun’s bright surface is blocked by the coronagraph one can see material moving outward in the Sun’s corona. However, the material the CME is made of is also from other parts of the Sun than from the corona. Some scientists have suggested the term ‘solar mass ejection’, but everyone was already so used to CME that the name remained.