Long description
The left-hand image (a) shows a picture of the Sun, taken through an ultraviolet filter that makes particular features clearer. The surface appears highly mottled due to convection cells. Several bright spots are visible from active regions. On the edge of the Sun’s disc, several pillars can be seen, as well as a large arch on the Sun’s top-right.
The right-hand image (b) shows a picture of the distant red supergiant star Gruis. The image is blurry, but still shows a circular disc. Dark lines can be seen on this image, indicating what are thought to be large convective cells. A bright spot is seen in the lower-right of the disc.