On February 2, the NEAR spacecraft resumed normal science operations after a brief hiccup. During preparations for a scheduled rocket engine burn, the spacecraft entered a safe hold.
The safe hold is a pre-programmed, automatic response by the spacecraft to an unplanned event which requires immediate corrective action. In this case, the spacecraft stopped all routine operations, pointed its medium gain antenna at Earth, and awaited further instructions.
Recovery from the safe hold and return to normal operations occurred on the afternoon of February 2, and the spacecraft successfully executed a revised engine burn on February 3 at noon EST (17:00 UT).
The cause of the safe hold was incorrect data input to the spacecraft attitude control system as onboard accelerometers were powered up, which resulted in a small autonomous engine firing. Fuel expenditure was insignificant.
Helen Worth, NEAR mission spokesperson at John Hopkins' said that an electical spike occured that exceeded operational parameters as the accelerometers were powered on. The reason why this is happening is not yet known, but as a precaution the accelerometers will be left on until the cause of the problem is determined. At this stage of the mission leaving them on is not a problem.
With the successful engine burn today, the NEAR spacecraft is back on course for arrival at Eros as planned on February 14.
NEAR managers in their latest science report confirmed that there was some lose of science observations that were scheduled to take place during the time that the spacecraft was in safe hold.
After another
