NASA beamed the first human voice ever heard from another planet back to Earth today, predicting a manned mission to Mars in a message transmitted from the surface of the Red Planet.
In the audio message, radioed to the Mars rover and then broadcast back to Earth by the Curiosity rover, NASA administrator Charles Bolden said a manned mission to Mars could happen "in the not too distant future."
"Since the beginning of time, humankind's curiosity has led us to constantly seek new life new possibilities just beyond the horizon," he said.
"The knowledge we hope to gain from our observation and analysis of Gale Crater will tell us much about the possibility of life on Mars as well as the past and future possibilities for our own planet.
"Curiosity will bring benefits to Earth and inspire a new generation of scientists and explorers, as it prepares the way for a human mission in the not too distant future.
"This is an extraordinary achievement. Landing a rover on Mars is not easy. Others have tried. Only America has fully succeeded."
At mission headquarters in California, Curiosity program executive Dave Lavery paid tribute to Neil Armstrong, the first man on the Moon, whose death was announced at the weekend.
"With this voice, another small step is taken in extending human presence beyond Earth, and the experience of exploring remote worlds is brought a little closer to us all," he said at mission headquarters in California.
"As Curiosity continues its mission, we hope these words will be an inspiration to someone alive today who will become the first to stand upon the surface of Mars.
"And like the great Neil Armstrong, they will speak aloud of that next giant leap in human exploration."
The voice message was released as NASA beamed back more spectacular pictures taken by the $US2.5 billion rover, which landed at Gale Crater on August 6.
One showed a panorama, in pin-sharp resolution showing individual rocks, of the landscape visible from the rover, including Mount Sharp, the slopes of which Curiosity plans to drive toward in the coming weeks and months.
Mission chief scientist John Grotzinger said the landscape looked like "something that comes out of a John Ford movie," referring to typical backdrop in films by the classic Western director.
And he compared the tyre tracks made by Curiosity, visible in some of the photos, to images of the first footprints on the Moon made by Armstrong, whose death at 82 was announced by his family at the weekend.
"What we are seeing here is the results of tracks involving the first motions of the rover. I think instead of a human it's a robot pretty much doing the same thing," Mr Grotzinger said.