8-21-17 TOTAL ECLIPSE of the sun viewed from Cades Cove, TN. n addition to bringing the sun’s corona into view, totality makes the surrounding sky so dark that viewers can see stars and planets during the day. On August 21, Venus and Jupiter will appear the brightest, as they will sit nearly halfway across the open sky during the eclipse. Mars and Mercury will be much closer to the sun, so will be fainter but still visible.