How the north ended up on top of the map is an article by Nick Danforth, author/curator of (The/Mid) Afternoon Map blog, detailing how the north-up orientation came to be the default orientation, looking beyond Eurocentrism to Byzantine monks and Majorcan Jews who set the path for modern cartography. If you want more information, you might enjoy the Wikipedia article on the history of cartography, or you can really dig deep with the three-volume text, The History of Cartography, which is available in full from the University of Chicago Press online, split into individual PDFs for each chapter. [more inside]
Past Thinking about Earth-Like Planets and Life [pdf], presenting a brief history of thought on finding extraterrestrial life-like phenomena, is the first chapter of James Kasting's new book, How to Find a Habitable Planet. He participated in a discussion on BBC's The Forum.