* Astronomy

NASA administrator Michael Griffin has decided to further extend the mission of the Tropical Rainfall Measuring Mission (TRMM) spacecraft, used in hurricane forecasting, perhaps until 2010; even though such an extension would make it impossible to carry out a controlled re-entry.

TRMM was scheduled to be shut down last year so that the spacecraft's remaining propellant could be used to deorbit the spacecraft in a controlled manner.
That decision was strongly opposed by scientists and members of the US Congress, who note that TRMM provides critical data used in forecasting hurricanes.



NASA then decided to extend TRMM to June 15 2005, a decision that would still save enough propellant to permit a controlled deorbit.

"NASA`s justification for the extension and eventual uncontrolled re-entry of the spacecraft is based on the expected benefits of continued operational use of TRMM data in the monitoring and forecasting of hazardous weather. We also considered public safety benefits of using TRMM information and the additional benefits to scientific research"- Erica Hupp, NASA spokeswoman

However, Griffin believes that the risk of injury or damage caused by an uncontrolled re-entry (estimated to be 1-in-10,000) is much smaller than the benefit gained by keeping the spacecraft operational.

With the controlled de-orbit requirement waived, TRMM is expected to last until at least 2010, when the first of a series of planned follow-on Global Precipitation Measurement Mission satellites is due to launch.

No formal announcement of the mission extension has been made.