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
Solar System Exploration Research Virtual Institute on one or more aspects of lunar science investigations of the Moon (including lunar samples), from the Moon, and on the Moon. In 2013 the NLSI became the Solar System Exploration Research Virtual Institute and expanded its scope to include Near-Earth asteroids and Phobos and Deimos. The Solar System Exploration Research Virtual Institute (SSERVI) is composed of thirteen U.S. teams, and ten international partners. The teams are listed below: US TEAMS: Focus: Formation of terrestrial planets and asteroid belt, modeling of the Moon's origin and Phobos/Deimos, history of NEAs and lunar bombardment, NEA origins, identification and characterization boulder.swri.edu Focus: Studies