Many satellite and robotic missions that have taken place in the past have documented the many river valleys of Mars and the riverbeds, revealing a landscape carved by an ancient and active water cycle. But today, the planet Mars is very dry, and if a new study is correct, what seems to be to blame is the size of the planet itself.
Wang, the lead author of a new study led by graduate student Zhen Tian and published this week in the Proceedings of the National Academy of Sciences, examined stable potassium isotopes in various meteorites whose origins are known to approach presence, levels and distribution of volatile substances that can be a tracer for the amount of water available.
By analyzing the composition of the Earth along with meteorites from Mars, the Moon and the asteroid 4-Vesta, the study authors found a well-correlated relationship between the size of a body and the abundance of this particular potassium isotope.
In addition, the 20 meteorites on Mars - 200 million years old to 4 billion years old - revealed that Mars lost its volatiles, including water, much faster than Earth did in the first billions of years of its formation.
According to some models, Mars in its early formation would be extremely similar to Earth, including an Earth-like thick atmosphere and stagnant water in surface of.
Mars lost its shielding magnetic field and the destruction of the solar winds removed much of its atmosphere, and all the water evaporated about a billion years after its formation.
Analysis: What does this mean for the search for extraterrestrial life?
The new study offers an important insight into the search for extraterrestrial life. While we have found thousands of exoplanets orbiting extraterrestrial stars, determining who are the best candidates to host life is a challenge.
The study of all these is currently impossible and many can be excluded from some data we already know. We can largely exclude planets that do not orbit within the "habitable zone" of the star, the theoretical zone around the star where there may be liquid water on the surface of a planetary body. But so the Venus as well as Mars exist within the habitable zone of our sun, and are currently both inhospitable to life.
This new study could add another important filter to our exoplanet data to restrict potential candidates for study, Wang said.
"The size of an exoplanet is one of the parameters that is easier to determine. "Based on size and mass, we now know if an exoplanet is a candidate for life, because size is a key first-order determinant of flight retention."
Source of information: techradar.com