IMO The image not only has no encyclopedic value whatsoever it has a negative value What one could possibly learn from that image The only thing that could be learned from this image is how not to take a similar image in order do not damage both your camera and your eyes The image quality is horrible It is full of camera artifacts On the other hand the image is highly encyclopedic It shows not only the sun sunspots and Mercury but also Limb darkening The image is a great illustration of the size of the Sun compare to Mercury It is easy to correct the caption under the image and provide the link to the Mercury transit article Then maybe somebody would go there and learn something new