Earlier this year, SpaceX founder Elon Musk said the company planned to send unmanned Dragon capsules to Mars by 2018. In hindsight, his designs may have proved a bit too ambitious and has since seen the company revise the deadline for 2020. 

Now, the method of getting to Mars has also been adjusted, with Musk noting that the Red Dragon capsule project is done, and that it will not be used for any future missions to land on Mars. The major reason for why Musk and SpaceX has called quits on Red Dragon's journey lies with NASA's safety standards, and concerns that the capsule will struggle to meet these.   

Instead, at the International Space Station Research and Development Conference, SpaceX will rather use a soon-to-be announced Mars landing system. While full details on the secondary plan are unknown, Ars Technica says it is designed to be slightly smaller than Red Dragon, as well as less expensive. 

Consequently, we'll have to wait and see what Musk and SpaceX has cooked up.