If you have ambitions of being one of the first people on Mars, listen up: A Dutch company says it is moving along with its plan to send four lucky Earthlings to colonize the Red Planet. The catch: They won't ever come back.

The Mars One foundation announced Tuesday that it has secured lead suppliers for an unmanned mission launching in 2018, which involves a robotic lander and a communications satellite. Lockheed Martin has been contracted to study building the lander, and Surrey Satellite Technology Ltd. will develop a concept study for the satellite, Mars One said.

This first mission will demonstrate technology that would be involved in a permanent human settlement on Mars. If all goes well -- and that's still very much an "if" -- the first pioneers could land on Mars in 2025.

Enthusiasm has been growing since the project's first big announcement in April. More than 200,000 people have signed up to be prospective astronauts, Mars One CEO Bas Lansdorp said in Washington on Tuesday.

Apparently, they're OK with living out the rest of their lives on Mars. The technology for a return flight doesn't exist -- there's no Kennedy Space Center launch pad over there! -- and having a one-way trip greatly reduces costs, the company has said.

The application period is now closed, and by the end of this year, the company plans to notify those special folk who made it to Round 2.

The unmanned mission is the "most important and most difficult step of actually getting humans to Mars," Lansdorp said.

It would also be the first privately funded planetary exploration mission.

"The opportunity to participate in that is just really exciting," said Ed Sedivy, a chief engineer at Lockheed Martin Space Systems