In US a tech billionaire Elon Musk said in a tweet on Sunday that one-way ticket to Mars will one day cost less than 500,000 US dollars. The price for the six to nine month trip could dip below a hundred thousand dollars. Musk said that the return journey could potentially be free of charge as time progresses. Musk said that most people in advanced economies could sell their homes on earth and move to Mars if they want. Musk's SpaceX is currently developing its starship that will move people to the space for taking on Mars. SpaceX plans to send a spaceship and a starship around the moon in 2023 with tourists on board.