Solar Prominence

A solar prominence is a large bright feature located in the solar corona. While the corona consists of extremely hot ionized gases, known as plasma, which do not emit much visible light, prominences contain much cooler plasma, similar in composition to that of the chromosphere. A prominence forms over timescales of about a day, and may persist in the corona for several weeks. Many prominences break apart and give rise to coronal mass ejections.

I just thought the pictures were pretty cool.