Leave aside for a moment the cost and risk of sending humans to Mars.

In a 2011 interview, he said he hopes to send humans to Mars' surface within 10-20 years.

A number of nations and organizations have long-term intentions to send humans to Mars.

In 2003, China became the third country capable of sending humans into space.

Rockets are too slow to send humans on interstellar missions.

"That's why they still have to send humans down there to root them out."

This achievement made China the third country to independently send humans into space.

China is the third country, after the United States and Russia, to have sent humans into space.

While there are no immediate plans to do so, Chinese officials also have expressed interest in sending humans to the moon.

The agency has long wanted to send humans to Mars.