<P> Future population growth, demand for resources, and an alternate solution to the Doomsday argument may require human colonization of bodies other than Earth, such as Mars, the Moon, and other objects . Space colonization will facilitate harvesting the Solar System's energy and material resources . </P> <P> In many respects, Mars is the most Earth - like of all the other planets in the Solar System . It is thought that Mars had a more Earth - like environment early in its history, with a thicker atmosphere and abundant water that was lost over the course of hundreds of millions of years . Given the foundations of similarity and proximity, Mars would make one of the most plausible terraforming targets in the Solar System . </P> <P> Ethical considerations of terraforming include the potential displacement or destruction of indigenous life, even if microbial, if such life exists . </P> <P> The Martian environment presents several terraforming challenges to overcome and the extent of terraforming may be limited by certain key environmental factors . </P>

What are the major effects of mars' lack of significant magnetic field