Space is an inhospitable environment for humans. Astronaut Scott Kelly has returned after a long stint on the ISS space station, he will now be studied to see the effects of long term exposure of Space on the human anatomy, this is all to assist the Mars space program, which I am not in favour of, as it is obvious that with current technology within the context of surviving long term space flight, we won’t do too well beyond the Earth’s magnetic fields. Apart from the high atmosphere Earth orbits, for short periods of time, any further for a human being is deadly. The main concern apart from physical changes, blood flow irregularity, shrinking heart, pressure on eyes and nervous system, is radiation; and since we haven’t got a cure for cancer on Earth, a constant exposure to galactic cosmic rays on astronauts will put them at a huge amount of risk in space. With radiation levels that exceed well over safe dosages, the main issue is ionizing radiation which does not decline in frequency in space. In other words constant bombardment of gamma rays on the human cells would kills us in weeks or days from acute radiation poisoning. So, whats the play? We need to create sophisticated bio-mechanical systems to do the exploring for us. In which we can Virtual Reality the results back on Earth. As far as human exploration goes, we can immerse with VR for the results and conquests of the solar system. The machines are our friend. In regards to human colonization of the solar system, I agree this needs to occur, but we need to develop a base on the moon (not Mars) to test new ways of exploring the neighboring planetary system, also advancements in new bio-tech, medical techniques and drugs. From an engineering perspective we need better space craft, propulsion etc. These should be designed and built in space. Astrobiological research should not be bothered with the surface of planets in our solar system, we need to build into the planets and moons. Not above ground bases. If cell/bacteria or even primitive life exists in our solar system, the AI and robotic systems should create the underground bases first to allow us to then travel to them – safely. The egocentric aspect for humanity to explore the solar system should step back to allow a complete machine assisted guidance.