Experts found a problem while searching for hydrated perchlorates on Mars maps.
Scientists at Caltech (USA) concluded that due to inappropriate data processing by the Mars Reconnaissance Orbiter interplanetary station, the device mistakenly recognizes the presence of hydrated salts on the red planet. Thus, some areas on the planet where the presence of water was previously assumed are in fact completely dry and lifeless.
Experts discovered a problem while searching for perchlorate hydrates on Mars maps, based on information obtained by the near visible and near infrared (CRISM) spectrometer. Perchlorate decreases the freezing point of water to 80 degrees Celsius, which makes it possible to have liquid water in the Martian atmosphere. The existence of perclorates on Mars is also known due to the Phoenix spacecraft landing on the surface of the planet and Curiosity Rover.
The presence of minerals on Mars, scientists are judged by reflecting different wavelengths on the surface of the planet. Chemicals absorb in a special way and reflect light. However, the CRISM camera is not always correct, so it detects reflected light spots where it should not be. Algorithms for correcting such mistakes sometimes make dips in spectra at the same wavelength as perchlorate. Scientists have written an algorithm that allows CRISM maps of small perchlorate deposits and the program has revealed the wide presence of salts on the surface of Mars, including where there are no conditions for their formation.
Now scientists are working on a more accurate method for recognizing perchlorate, which is based not only on spectral data. According to the researchers, the perchlorates present on Mars, however, made it clear that they are much harder to detect than previously thought.