A two-inch tear in the foil covering the insulation of a probe that is to accompany NASA's Cassini craft on its mission to Saturn could delay the scheduled 6 October launch, agency officials said today.
The tear in the Huygens probe covering was caused by excess airflow in the craft's air conditioning system. This incident is the second problem with the Cassini to crop up in the past month. On 8 August, the Lockheed Martin and Air Force engineers announced that they had found a liquid hydrogen leak in the Centaur stage of Titan IV launch vehicle.
Cassini is slated to orbit Venus and then use a gravity-assisted flyby of Earth to propel it to Saturn, where the craft will fall into orbit and conduct the brunt of its studies. To make the orbits and carry out all the scientific objectives, NASA said it must launch the craft within the window of 6 October and 4 November.
A contingency period, lasting until 15 November, would also allow a launch, but would compromise parts of the mission because of the greater distance and fuel needed to reach the orbits.
Cassini has been under constant scrutiny because the 72 pounds of plutonium used to power its scientific instruments would be the most ever launched into space. NASA contends that it has no other power source for a mission that will take place so far from the sun, but critics, including a growing number in Congress, believe otherwise and advocate the use of solar power.
At a briefing today, both NASA and the European Space Agency, which built Huygens, characterized this latest problem as "insignificant" and said technicians would work around the clock to repair any damage so the mission could make its scheduled launch window.
