On March 12, 2012, Sunsflare posted a video asking if anyone could identify a circular object seen in SDO coronal images.
The video was also posted on Facebook with the same question posed. I answered the question on Facebook but here is a more detailed response and discussion of the observation. The object seen is a coronal cavity associated with a filament. There was also an eruption of the filament with a CME.
The original video and the response have since been removed.
Finally, I put together this more detailed response to discuss the observation.
