This ultraviolet image near Mars» South Pole was taken by MAVEN on July 10 2016 and shows the atmosphere and surface during southern spring. (ibtimes.com)
The marine geologist and first author of the study explains, «Only in the short southern spring and summer, for just a few months in the year, was there a marked stratification at the ocean's surface. (sciencedaily.com)
Messier's galaxies are not deitributed equally across the sky, but can be grouped into a large group of Northern Spring / Southern Fall, and a smaller Northern Fall / Southern Spring group: (maa.clell.de)