Category: Science / December 4, 2012 10:15 AM EST
No definitive signs of life have been found on Mars so far, said the National Aeronautics and Space Administration in San Francisco on Monday.
The announcement came after the Curiosity rover completed its first chemical test of Martian soil, stirring up public speculation that the rover had found signs of life.
During the NASA press conference Monday, people's attention is on SAM - Sample Analysis at Mars -- an instrument that takes up half of Curiosity's weight.
However, the opening words by the scientist at the press conference seem to have disappointed many.
"Let me start off by saying that SAM has no definitive detection to report of organic compounds," said Paul Mahaffy, principal investigator for Curiosity's SAM.
Scientists said a sample of sandy soil analyzed by the rover's lab contained water and a mix of chemicals, but not the complex carbon-based compounds considered necessary for life.
The rover did find a simple carbon compound, but scientists have yet to determine whether it is native to the Red Planet, or came from elsewhere.