"The spacecraft sent limited data in a proper response to a ground command, and we're planning for commanding further communication sessions later today," Mars Exploration Rover Project Manager Pete Theisinger said.Source: Reuters
The six-wheeled craft landed on the red planet on Jan. 3 for a planned three-month mission. Officials had described the loss of communications as a "very serious anomaly."
The scientists reported on Thursday Spirit had radioed a signal indicating it was receiving Earth transmissions even though it had not resumed sending data back to Earth.
Spirit had been unable to return any science or telemetry data since early Wednesday. Spirit landed on Mars on Jan. 3 on a planned three-month mission to explore the geologic history of the planet.
NASA receives signal from Spirit after the recent communication problems

Last few days NASA had a few communication problems with the Spirit Mars rover, but today they have again received data coming from Spirit starting at
8:26am EST and continuing for 20 minutes.