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Humans may not have landed on Mars (火星 ) just yet, but that isn' t stopping a European company from devising a plan to send four people to the Red Planet within the next few years. This project, called Mars One, aims to send a small group of people to Mars in 2022 and eventually es-tablish a permanent colony on the planet.
"Everything we need to go to Mars exists," said Mars One co-founder Bas Lansdorp in March 2014. "We-have the rockets to send people to Mars, the equipment to land on Mars, the robots to prepare the settlement for humans. For a one-way mission, all the technology exists. " Yet the four astronauts ( 宇航员) chosen for the trip will be stuck on Mars--forever. And despite Mars One' s thorough planning, there are a number of challenges that may prevent the mission from ever taking place. The biggest road block could be the mission' s huge cost(S6 billion). However, Lansdorp is confident that Mars One will be able to fund the project by selling the broadcast fights for the mission and subsequent experiences living on the planet.
Those broadcast fights will also play a part in helping to select the people who will be sent to Mars. Lansdorp said the company will .hold a selection process similar to a reality show. Lansdorp is expecting at least 1 million applications from people around the world. In addition to the cost,
several other potential problems could inhibit ( 阻止) the mission to Mars."It' s even more challenging to send people there with life support, with food, with air, with all the other things like books, entertainment, means of communication and means of providing for their own resources for a long stay on Mars," said Adam Baker, senior lecturer in space engineer-ing at Kingston University in London. "The sheer size of the rockets you' d need to do this would be absolutely colossal. "
 According to Project Mars One, humans could send four people to Mars within the next____________ years.