Mars Express Observes The Red Planet

Scientists using ESA’s Mars Express have produced the first crude map of aurorae on Mars. These displays of ultraviolet light appear to be located close to the residual magnetic fields generated by Mars’s crustal rocks. They highlight a number of mysteries about the way Mars interacts with electrically charged particles originating from the Sun.

The aurorae on Mars were discovered in 2004 using the SPICAM ultraviolet and infrared atmospheric spectrometer on board Mars Express. They are a powerful tool with which scientists can investigate the composition and structure of the Red Planet’s atmosphere.

Now Francois Leblanc, from the Service d’Aéronomie, IPSL/CNRS, France and colleagues have announced the results of coordinated observation campaigns using SPICAM, the MARSIS sub-surface sounding radar altimeter’s radar, and the energetic neutral atoms analyser, ASPERA’s electron spectrometer on Mars Express.

They have observed nine new auroral emission events, which have allowed them to make the first crude map of auroral activity on Mars. They see that the aurorae seem to be located near regions where the martian magnetic field is the strongest. MARSIS had previously observed higher-than-expected electrons in similar regions. This suggests, although it does not prove, that the magnetic fields help to create the aurorae.

On Earth, aurorae are more commonly known as the northern and southern lights. They are confined to the polar regions and shine brightly at visible as well as ultraviolet wavelengths. The existence of similar aurorae is well known on the giant planets of the Solar System. They occur wherever a planet’s magnetic field channels electrically charged particles into the atmosphere.

More information available at esa.int