Though all our eight planets are wildly different from one another today, some similarities can still be spotted. Even if our environment and topography separate us from the rest, we may be able to find morphological similarities with other planets during various stages of development. One such theory being proposed is that a crater on Mars might have been very closely similar to Iceland, 3 billion years ago. The similarity is based on weather, topography, and so on between the two formations.
Once upon a time, The Gale Crater’s seasons might have been exactly like today’s Iceland. The observation was made by Rice University scientists with data from Curiosity Mars Rover.
Iceland on Earth has a basaltic terrain and as the name suggests, rather cool weather. The study found similar temperature, i.e. 380 F might have been the condition on the crater. Not only that, but they also suggest this temperature could have impacted the rock formation and sediment deposit by ancient streams.
According to their observations, there must have been a lake within the crater once. But people still don’t know how water reached the red planet. Some experts suggest early Mars was warm and wet, making it a good home for rivers and streams. Some say it was cold and dry, which would make snow and glacier more common than liquid water.
“Sedimentary rocks in Gale Crater instead detail a climate that likely falls in between these two scenarios. The ancient climate was likely frigid but also appears to have supported liquid water in lakes for extended periods of time,” said Michael Thorpe, one of the researchers.
They analysed a river-fed sedimentary plain in Iceland and discovered the constituents were similar to that of what they suppose ancient Gale crater would have been.
According to Thorpe, sedimentary rocks on Earth mature and chemically weather over time. However, the sample from Mars suggests there was limited weathering as there were very young minerals in the mudstones that are older than any sedimentary rocks on Earth.
A process called the chemical index of alteration (CIA) is used to infer past climates (even on earth) based on chemical and physical weathering of a sample.
Flowing water erodes and weathers rocks and any soluble chemical components can be dissolved. But on the Mars observation, they discovered something different.
“Only a small fraction of the elements that dissolve the fastest had been lost from the mud relative to volcanic rocks, even though the mud has the smallest grain size and is usually the most weathered,” said Kirsten Siebach, Martian geologist.
Based on this, they inferred average annual temperature on Mars must be very limited when the lake was there. If it were warmer, the elements would have been flushed away. This also indicates the climate shifted from Antarctic-like conditions in the beginning to Icelandic later on.