A Princess of Mars Lowell published two more books, further developing the concept of a dying Mars. Burroughs was aware of these theories and appears to have consciously followed them. However, Burroughs does not seem to have based his vision of Mars on precise reading of Lowell's theories, as there are a number of errors in his interpretation which suggest he may have got most of his information from reading newspaper articles and other popular accounts of Lowell's Mars. The ideas of canals with flowing water and an inhabited, if dying world, were later disproved by more accurate observation of the planet, and fly-bys
Astrobiology restricted to the surfaces of planets. The three most likely candidates for life in the Solar System are the planet Mars, the Jovian moon Europa, and Saturn's moons Titan, and Enceladus. Mars, Enceladus and Europa are considered likely candidates in the search for life primarily because they may have underground liquid water, a molecule essential for life as we know it for its use as a solvent in cells. Water on Mars is found frozen in its polar ice caps, and newly carved gullies recently observed on Mars suggest that liquid water may exist, at least transiently, on the planet's