The Mars radiation environment instrument aboard the Mars Odyssey spacecraft has failed, but engineers hope that it can be restored. The spacecraft is 18.5 million km (11.5 million miles) from Earth and heading at a speed of 24km/s for an orbital insertion around the Red Planet on 23 October. The spacecraft's other instruments - a thermal emission system with infrared and visible camera and a gamma ray, neutron and electron spectrometer - are working.
Source: Flight International