Mars and seasonal cycles of Mars are likewise similar to those of Earth, as is the tilt that produces the seasons. Mars is the site of Olympus Mons, the largest volcano and second-highest known mountain in the Solar System, and of Valles Marineris, one of the largest canyons in the Solar System. The smooth Borealis basin in the northern hemisphere covers 40% of the planet and may be a giant impact feature. Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids, similar to 5261 Eureka, a Mars trojan. There are ongoing investigations
How Much for Just the Planet? How Much for Just the Planet? How Much for Just the Planet? is a 1987 "Star Trek" tie-in novel by John M. Ford. In the novel, large deposits of dilithium are detected on a colony planet, and delegations are sent by the United Federation of Planets and the Klingon Empire to negotiate for mining rights (neither able to openly fight against the other because of the "Organian Lightbulbs", a reference to the Organians from the original series). They find the planet Direidi and its inhabitants to be very strange indeed. Planet inhabitants occasionally break into song to explain their narratives