LOS ANGELES, May 25 (Xinhua) -- After traveling for almost 10 months, Mars Phoenix Lander successfully landed on the Red Planet on Sunday on a mission to explore signs of life, according to NASA's Jet Propulsion Laboratory (JPL).

      With a speed of 13,000 mph when it reached the Martian atmosphere, the Phoenix Lander achieved a three-legged touchdown with the help of a parachute and pulsing retro rockets to slow down the spacecraft, the JPL said.

      Scientists managing the flight at JPL in Pasadena, Los Angeles cheered in celebration as the Phoenix Mars Lander signaled back that it had survived Sunday's fiery entry.

      "We're on the surface," Project Manager Barry Goldstein said.

      When asked whether the landing could have gone any better, Goldstein said, "not in my dreams."

      "Six minutes of sheer terror." That's what the usually understated scientists at the JPL were calling the landing of the Mars Phoenix Lander.

      "Six months of boredom, in this case 10 months of boredom, followed by six minutes of sheer terror, just because we are landing on another world and it's completely autonomous -- there's no second chances," JPL Project Payload Manager Michael A. Gross said.

      The 420-million-dollar mission blasted off last August on its nine-month, 422-million-mile flight from Earth to Mars.

      Of 11 previous attempts that various nations have made to land spacecraft on Mars, only five have succeeded.

      Phoenix landed farther north on Mars than any previous mission, at a site expected to have ice-rich permafrost beneath the surface, but within reach of the lander's robotic arms, which are used to search for signs of life, past or present.

      These would be one of the biggest scientific discoveries in history.

      Phoenix will be the first spacecraft to study the Martian arctic plains. Unlike NASA's mobile twin rovers, the lander will stay in one spot.

      "We are ready to robotically operate our science lab in the Martian arctic and dig through the layers of history to the ice-rich soil below," said Phoenix Principal Investigator Peter Smith of the University of Arizona.

      Phoenix is equipped to study the history of the water now frozen into the site's permafrost, to check for carbon-containing chemicals that are essential ingredients for life, and to monitor polar-region weather on Mars from a surface perspective for the first time.

      Mars is a cold desert planet with no liquid water on its surface. But in the Martian arctic, water ice lurks just below ground level.

      Discoveries made by the Mars Odyssey Orbiter in 2002 show large amount of subsurface water ice in the northern arctic plain. The Phoenix Lander targets this circumpolar region using a robotic arm to dig through the protective top soil layer to the water ice below and ultimately, to bring both soil and water ice to the Lander platform for scientific analysis.

      According to NASA, the complement of the Phoenix spacecraft and its scientific instruments are ideally suited to uncover clues to the geologic history and biological potential of the Martian arctic.

      Phoenix will be the first mission to return data from either polar region providing an important contribution to the overall Mars science strategy, "Follow the Water," and will be instrumental in achieving the four science goals of NASA's long-term Mars Exploration Program: determine whether life ever arose on Mars; characterize the climate of Mars; characterize the geology of Mars; and prepare for human exploration.

      The Phoenix Mission has two objectives to support those goals, which are to study the history of water in the Martian arctic and search for evidence of a habitable zone and assess the biological potential of the ice-soil boundary.

      Phoenix will assess the habitability of the Martian northern environment by using sophisticated chemical experiments to assess the soil's composition of life-giving elements such as carbon, nitrogen, phosphorus and hydrogen.

      Identified by chemical analysis, Phoenix will also look at reduction-oxidation molecular pairs that may determine whether the potential chemical energy of the soil can sustain life, as well as other soil properties critical to determine habitability such as pH and saltiness.

      The Phoenix landing would have happened 15 minutes earlier on Mars, but the radio signals take 15 minutes to travel from Mars to Earth at the distance currently separating the two planets.

      If all goes as planned, the first pictures from Mars could arrive around 6:30 p.m. (0130 GMT on Monday), JPL scientists said.