Scientists have learned a lot about Mars in recent years, and based on observations from the fantastic hardware that NASA sent to the Red Planet, we know that it has ever held much more water than we see today. But knowing that there has been a lot of water on Mars (or at least plenty of ice) long ago does not necessarily tell us what the climate is like.
Without a time machine, we cannot know what ancient Mars looked like, but researchers have come up with a pretty solid assumption. Using data from NASA's CRISM spectrometer and Curiosity rover, scientists have a good idea of what types of minerals are present in Martian soil. Using different areas of Earth as analogues, they can observe the conditions that have caused such models of deposition of minerals on our planet and accept that a similar climate was responsible for their formation on Mars.
At the Goldschmid Geochemistry Conference in Barcelona this week, Purdy University professor Briony Horgan announced the findings of a new research effort that compares the climate of present-day Earth to that of ancient Mars.
"Our study of atmospheric influences under radically different climatic conditions, such as the Oregon, Hawaii, Iceland and other places on the Earth, can show us how climate affects the model of mineral deposition, as we see on Mars," said Horgan . "This leads us to believe that on Mars 3 to 4 billion years ago we had a general slow tendency from warm to cold, with periods of thawing and freezing."
The study delves deep into the nuances of various mineral deposits, such as silicon dioxide, which scientists believe hints at melting ice. This suggests that the planet has had some ups and downs in temperature, with warm periods characterized by occasional rains and then colder periods in which everything has been frozen.
Mars today is frigid compared to Earth and this is largely due to the fact that the atmosphere of the planet is almost completely taken away. Billions of years ago, it is believed that the planet had a much healthier atmosphere that would help retain heat. The temperate climate with rain and running water certainly sounds like a recipe for life as we know it, but we may have to wait and see what the Mars 2020 Rover has to say after it arrives in early 2021