Mars | The Perseverance rover collects data on Mars with equipment developed by Finns

The new ones information about the planet Mars always arouses widespread interest, not least because the planet is being searched for signs of life or its remains. Finnish planetary scientists are also involved in the study of Mars.

The Finnish scientific community has focused on researching especially the gas atmosphere of Mars, weather phenomena and the water cycle. New observational data is obtained from the Perseverance rover of the US space administration, which landed on Mars in 2021.

The study of the gas atmosphere of Mars can also provide information about the Earth’s atmosphere.

“Observations on Earth are messed up by, among other things, vegetation and water bodies, which do not exist on Mars. Mars is a simpler reference laboratory that can be used to develop different models and deepen the understanding of certain physical processes,” sums up the senior researcher at the Finnish Meteorological Institute Jouni Polkko.

With the help of geophysical planetary research, it is also possible to model the conditions of other planets, even exoplanets.

Elucidating the water cycle of Mars, known as the red planet, can also help in solving a big riddle: where did all the water disappear, which is estimated to have been abundant on the surface of Mars in the past.

Polko belongs to the group of researchers that was published in the Icarus science journal research About the weather phenomena and water cycle of the Martian Jezero crater. The study is based on the observations of the ATV and the emeritus professor of meteorology at the University of Helsinki Hannu Savijärven to a column model that predicts the time evolution of temperature and humidity.

The subject of the review was a special case where a dust storm sweeps past the observation site. The relative humidity of the gas atmosphere at 1.45 m height observed at normal wind speed was high at dawn, 40–90 percent.

According to model experiments, with a weaker night wind, the humidity in the gas atmosphere near the surface would be even higher, says a member of the research group Joonas Leino From the Institute of Meteorology.

Although the relative humidity can be very high, the absolute humidity is low because of the frost.

Using the column model, a process called adsorption has also been observed. In it, water molecules in the gas atmosphere stick to the Martian surface as the temperature drops as the sun sets. In the morning, however, the water molecules are released back into the atmosphere as the temperature rises.

The background of the phenomenon is a strong temperature variation, which can be as much as 70–90 degrees between day and night temperatures.

SUV size Perseverance makes observations with pressure and humidity measuring devices developed by Vaisala and the Finnish Meteorological Institute. Similar meters are also used in the Curiosity rover.

The roots of Finnish Mars research go back to the end of the 1980s. Devices developed by the Finnish Meteorological Institute and its partners were used, for example, in the Soviet Union’s Fobos probes and NASA’s Phoenix, which landed on Mars in 2008.

There have been great successes in exploring the Red Planet, but not everything has always gone smoothly. For example, some probes have crashed on the surface of Mars or the connection with them has been lost.

The Finnish Meteorological Institute was also involved in the Russian and European space agency Esa’s ExoMars project, where the goal was to search for signs of life on Mars. The probe was almost ready, but Esa withdrew from the project after Russia attacked Ukraine.

Martian water has been chased for decades, Polkko describes.

Geological research data tells about water. It is difficult to explain Marsperä’s riverbeds and other landforms without free water and a thicker gas atmosphere than today.

Today, the air pressure on Mars is so low that it vaporizes liquid water on the surface. However, at a depth of a good ten kilometers, there can be a huge water reserve. This is what is published in the journal PNAS of the American Academy of Sciences research.

The discovery is based on observations of the subsurface structure of Mars by the InSight probe, which measures earthquakes.

Indications of a water reserve increase hopes that signs of life would be detected.

“Perhaps prebiotic chemistry appeared on the planet, i.e. a precursor of life or primitive life, which has since died or retreated to shelter deep in the soil. It could be in hibernation or fossil remains could be found.”

According to Polko, finding life on Mars is unlikely. It’s still worth looking for, because the discovery would be revolutionary.

In terms of the discovery of life, it would be of the same importance in itself, what kind of traces of objects would be observed.

“Astrobiology uses the code LGM, i.e. “little green men”. It can be a little green man as well as a primitive single-celled bacterium.”

Travel Mars has fascinated science fiction writers for a long time, but it has since become a scientific goal as well. The task is not easy. For example, one should solve a large number of technological problems and be able to protect space pilots from cosmic radiation.

There has been less talk about preventing pollution, which according to Polko causes a lot of trouble. It is necessary to solve how to prevent the migration of Earth’s organisms to contaminate Mars and vice versa.

“Man is such a snot bag that contamination is a real risk. For example, around 10,000 species live in us”, a large part in the intestines.

Taking a human to Mars and bringing him back alive would also involve huge costs. With robot probes, there is no need to worry about bringing them back to Earth.

Polkko thinks that a manned flight could only be realized in the 2040s.

“There is also a lot of work in the nearby areas, such as returning to the Moon and building a base there. The new Gateway space station should also be built as a successor to the ISS (International Space Station) in orbit around the Moon.”