Houston, Aug 6 - In a moment of triumph for outer space exploration, NASA's most modern spacecraft successfully landed on Mars today to begin a pioneering two-year search to find out if the red planet once hosted conditions suitable for life and whether it can be inhabitable in the future.

The USD 2.5 billion robotic 'Curiosity' made a spectacular landing near the foot of a mountain 4.8 kilometres tall and 154 kilometres in diameter inside Gale Crater, said NASA.

"Touchdown confirmed," the triumphant NASA engineer Allen Chen claimed in the control room as America's most high-tech interplanetary rover survived a harrowing plunge through the Mars' thin atmosphere to touch down on the red planet at 05:30 GMT (11:00 IST).

Just minutes after the signal arrived that the landing had gone off successfully, Curiosity beamed back its first black- and-white thumbnail image of Mars. Soon after, a bigger image 256 by 256 pixels large showed up onscreen at the laboratory.

The spacecraft is the largest and most advanced ever sent to another planet. The car-size, one-tonne rover's descent- stage retrorockets fired, guiding it in a "sky crane" manoeuvre to the surface of the Mars.

Applause erupted across the campus of the Jet Propulsion Laboratory in La Canada Flintridge and engineers inside mission control could be seen hugging and weeping with joy as it received the first photos from its Curiosity rover.

"Curiosity, the most sophisticated rover ever built, is now on the surface of the Red Planet, where it will seek to answer age-old questions about whether life ever existed on Mars -- or if the planet can sustain life in the future," said an ecstatic NASA Administrator Charles Bolden.

"Today, the wheels of Curiosity have begun to blaze the trail for human footprints on Mars," he said.  PTI