Mars One is a private sector endeavor to send human beings to Mars. The estimated cost of $6 billion will be raised by selling T-shirts and hosting reality shows. In theory, the mission will launch in 2023. In order to reduce costs, astronauts will not be returned to earth. In other words, this is a one-way trip
There are a lot of technical issues that the sponsors have failed to adequately evaluate. Although they acknowledge high radiation exposure, resulting in a much higher probability of developing cancer (without a realistic ability to treat), they have set the launch date for a period of high solar activity, which dramatically increases the risks to the astronauts during transit. In order to reduce radiation exposure on Mars, astronauts will be largely confined to living underground, which poses psychological risks.
Energy generation is proposed to come from solar panels. However, Mars receives 4-times less solar energy than earth. It is also susceptible to dust storms, which would reduce solar energy output to virtually zero. If the storms last longer than a few days, the astronauts will be toast. The solar energy available during winter months is also reduced considerably. The Mars rovers that relied upon solar panels had to shut down during the winter. Such an option is not available to astronauts, who must rely upon energy for heating, oxygen production and water production.
Supplying astronauts with enough food is also a problem. The Mars One website says astronauts will raise their own food. However, this idea is very unrealistic. Even on earth, it took a tremendous amount of land to produce enough food to feed people in the Biosphere 2, who complained that they were always hungry. The Biosphere experiment also suffered from reduced oxygen and high carbon dioxide, which killed many species within the Biosphere. Problems on Mars could not be solved as easily as pumping oxygen from the outside, which was done for the Biosphere.
If problems or illnesses arise on Mars, help is at least 7-12 months away. So, this mission truly is a suicide mission. Fortunately, the sponsors will probably never get enough money to get the mission off the ground.