Mars is 250 million miles from Earth at the farthest point in the planets' orbits. Sheer distance makes unpredictable weather, unexpected illness and even homesickness potentially deadly problems. Residents of the future Mars base won't be able to count on a rescue mission.
For other Devil's Trumpet, see Datura (disambiguation). Datura is a genus of nine species of poisonous vespertine flowering plants belonging to the family Solanaceae. They are commonly known as daturas, but also known as devil's trumpets, not to be confused with angel's trumpets, its closely related genus Brugmansia.
In surveying and geodesy, a datum is a reference system or an approximation of the Earth's surface against which positional measurements are made for computing locations. Horizontal datums are used for describing a point on the Earth 's surface, in latitude and longitude or another coordinate system.n approximate definition of sea level is the datum WGS 84, an ellipsoid, whereas a more accurate definition is Earth Gravitational Model 2008 (EGM2008), using at least 2,159 spherical harmonics.