 Disadvantages of rovers compared to orbiters are the higher chance of failure, due to landing and other risks, and that they are limited to a small area around a landing site which itself is only approximately anticipated.Rovers arrive on spacecraft and are used in conditions very distinct from those on the Earth, which makes some demands on their design.Rovers have to withstand high levels of acceleration, high and low temperatures, pressure, dust, corrosion, cosmic rays, remaining functional without repair for a needed period of time.