A faulty instrument on Mars Express is up and running again after a "few months" out of action. The Planetary Fourier Spectrometer (PFS) went offline in July this year when its pendulum motor broke down. Once mission scientists were able to establish the cause of the problem, they switched to the back up motor and the PFS is back in business.

The PFS is designed to take very precise measurements of the distribution of the main gases that make up the Martian atmosphere, as well as measuring how temperature and pressure change with altitude, and tracking how this changes with the seasons.

It was the PFS that made the first ever in-situ measurements of methane in the Martian atmosphere, and also discovered traces of formaldehyde in the soil, provoking even more speculation than usual that there might be life on the red planet.

Now that the instrument has been switched back on, it will be able to start gathering data again almost immediately, mission managers say.

In related news, ESA said this week that there is a "small hope" that the student-built Sseti satellite would recover from its power problems. After a successful launch, the satellite was quickly put into safe mode after it emerged that there is a problem with charging its batteries.

In a bid to make the best of a bad situation, those in charge of the project stress that many of its goals have already been achieved. Project manager Neil Melville said that the mission had been a success from "an educational and technical standpoint". ®

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