...a photo of a Martian sunset taken by Spirit at Gusev crater, May 19, 2005.
Actually there is a reason. I was listening to the The Cosmic Ocean, a two part radio series about water and life in the universe presented by Leo Enright (and originally broadcast in 2004). Enright makes quite a nice jump from red ochre handprints in Lascaux some 17,000 years ago to the bumping imprint of a space craft on the dusty red Martian surface today.
The programmes helped bring into focus for me that one can think about life in three parts: 1) the life that is 'already here' on Earth [and so much of which we are destroying]; 2) the life that humans may or may not create this century through synthetic biology etc; and 3) the life that is, or may be, 'already there' in space.
Thinking, too, about maps and dreams, imagination and discovery, from Martin Behaim's Erdapfel to Giovanni Schiaparelli's first map of Mars and beyond.