U.S. President Barack Obama has said that the U.S. will send Americans to Mars by the 2030s, and return them “safely to Earth,” with a longer term goal of making it possible to “one day remain there for an extended time,” in a new op-ed published on CNN. The President highlight the need for cooperation between public and private space interests in meeting that goal, noting that private companies will send astronauts to the ISS within the next two years as a sign of forward progress.

Obama’s letter includes a fond remembrance of excitement around America’s early space program, and a reminder that the original space race resulted not just in advancements in the field of astrophysics, but also in considerably progress around technology in general, and in the medical field. He adds that it also had a net positive effect when it comes to inspiring “a new generation of scientists and engineers with the right stuff to keep America on the cutting edge.”

The President recaps some of the largest achievements made by NASA since, including the discovery of flowing water on Mars, and reiterated that the U.S. is working in earnest with commercial partners on new habitat modules that can help astronauts safely travel to, and be sustained during, long-term missions that could bring them to and back from the red planet. NASA committed $65 million across six companies to develop and test such deep-space habitats earlier this year.

President Obama doesn’t mention them by name, but SpaceX and Boeing are likely key components of the plan to get Americans to Mars. The two companies are slated to become the first private providers of astronaut transportation services to the ISS, which Obama did mention.

Habitat development will be a key ingredient in creating a viable Mars mission for humans, since risks including prolonged exposure to radiation will require solutions. During his recent presentation detailing SpaceX’s plan to get to Mars, Musk fielded a question about radiation fairly casually, noting that exposure risk wouldn’t be “deadly” in the amounts likely for the trip.