In the seventeenth and eighteenth centuries it became possible to believe in the existence of life on other planets on scientific grounds. Once the Earth was no longer the center of the universe according to Copernicus, once Galileo had aimed his telescope at the Moon and found it a rough globe with mountains and seas, the assumption of life on other planets became much less far-fetched. In general there were no actual differences between Earth and Venus, since both planets orbited the Sun, were of similar size, and possessed mountains and an atmosphere. If there is life on Earth, one may ponder why it could not also exist on Venus. In the extraterrestrial life debate of the seventeenth and eighteenth centuries, the Moon, our closest celestial body, was the prime candidate for life on other worlds, although a number of scientists and scholars also speculated about life on Venus and on other planets, both within our solar system and beyond its frontiers. Venusians: the Planet Venus in the 18th-Century Extraterrestrial Life Debate (PDF), from The Journal of Astronomical Data (JAD) Volume 19, somewhat via NPR and their mention of amateur astronomer Thomas Dick's estimations of the populations of the other planets in our solar system (Archive.org online view of Celestial scenery, or, The Wonders of the planetary system displayed, 1845).
If the Moon Were Only 1 Pixel is a tediously accurate model of the Solar System that Josh Worth made to explain to his daughter just how difficult it is to go on holiday to Mars.
I am a staunch believer in leading with the bad news, so let me get straight to the point. Earth, our anchor and our solitary haven in a hostile universe, is in a precarious situation. The solar system around us is rife with instability.[more inside]
The cosmos is also within us, we're made of star-stuff. We are a way for the cosmos, to know itself.
Cosmos: A Personal Voyage is a thirteen-part television series of one hour shows written by Carl Sagan, Ann Druyan, and Steven Soter, that was aired at the tail end of 1980 and was - at the time - the most widely watched series in the history of American public television. It is best introduced by an audio excerpt of one of his books, The Pale Blue Dot. Inside is a complete annotated collection of the series. [more inside]
What lives where in the Solar System. Fantastic Adventure covers from 1939/40 depicting the kind of lifeforms they think each planet can support. [more inside]
Take a tour of the solar system! Tonight, see the wonders of Mercury, Venus, Jupiter, Mars and Saturn! There's only one catch: You'll need to actually step outside to do it. [more inside]
What if other planets in the Solar System orbited Earth at the same distance as the Moon? (SLVimeo) Full screen highly recommended.
8 Wonders of the Solar System, Made Interactive. "What might future explorers of the solar system see? Find out by taking an interactive tour through the eyes of Hugo Award-winning artist Ron Miller. Text and narration by Ed Bell." [Via]
At forty miles (64.4 km) from Pluto to Sun, the Maine Solar System Model is the largest complete three-dimensional scale model of the solar system in the world. What, you didn't know there was more than one? And yes, Pluto is staying put.
Saturn's enigmatic moon Titan holds on to its mysteries. Radar images reveal quite a bit of variation but no clear interpretation. The hazy atmosphere prevents the sudden shock of discovery that characterized the Voyager and Galileo flybys of the moons of Jupiter, revealing little more than fuzzy Rorschach blobs. With less than 1% of the surface mapped, researchers suspect that Titan has a young surface shaped by processes that have yet to be revealed.