Brussels, 16 Jul 2004
Europe's Mars Express spacecraft may have detected ammonia in the atmosphere around the Red Planet; a sign that some scientists believe could point to the existence of life.
Researchers from the European Space Agency (ESA) say that sensors carried on board Mars Express have tentatively detected the spectral signature of ammonia, reports the BBC.
The reason why the discovery of ammonia, if confirmed, would be so intriguing is that it can only survive for a short period of time in the atmosphere of Mars, and therefore it must be getting continuously replaced. The two most obvious sources of replenishment are active volcanoes, none of which have been discovered yet on Mars, or microbes.
The spectral signature of ammonia was detected by the Planetary Fourier Spectrometer (PFS) instrument on board the orbiting spacecraft. The principle investigator for the instrument is Professor Vittorio Formisano, who is expected to publish the latest results from the instrument at a meeting in Paris next week.
Although the PFS instrument has been operational for some months now, only a small proportion of its data has been analysed due to the complexity of the task. However, it is evidence of the existence of minor compounds that is generating the greatest interest.
Scientists have already detected methane in the Martian atmosphere, another gas with a possible biological origin. Before getting too excited by the evidence of ammonia, however, the team had to rule out the possibility that it may have originated from the air bags of the failed Beagle 2 lander. However, analysis showed that the distribution of the gas did not support this explanation.
If the presence of ammonia is confirmed, future missions could set out to determine whether it has a biological or volcanic origin. However, one NASA scientist told the BBC that: 'There are no known ways for ammonia to be present in the Martian atmosphere that do not involve life.'
To find out more about the Mars Express mission, please consult the following web address: