Life on Mars will be very hard. The psychological ramifications of being isolated for so lang can be devastating and unpredictable at this point. Space travel can play a strange game with the mind and then there’s the planetary isolation. The brain can suffer terribly from this situation and therefore depression is almost certainly an enemy of the Mars pioneers. This could lead to a mission failure! The Mars milieu can also create obstacles. Low gravity and radiation make it very hard and virtually impossible to survive. The pressure in the skull, caused by the difference in gravity, could damage the eyes and the facial nerves. Then there’s the surface dust that hurtles up due to the thin atmosphere and low gravity. The lungs and eyes could be facing troublesome effects in these conditions. There’s no electromagnetic field, at least not in the way that we experience it on Earth. This in connection with the thin atmosphere could leave us virtually defenseless against harmful radiation. This could cause damage to the proteins in the cell structure and our DNA and result into fertility problems and even cancer. As the gravity is only one third of that on Earth it gives less pressure on bones and muscles causing them to deteriorate. Even if NASA doesn’t admit that there is life on Mars we are absolutely sure that microscopic life will be present. Everything points in that direction. These could cause problems to the human immune system, although we are not sure yet. But it is most likely that microscopic life could be dangerous.