How long do you think Mars had Valles Marineris?

Answer 1

One research group estimates that Valles Marineris is at least 3.5-billion years old.

Answer 2

Estimated ages vary quite a bit. My own opinion, based on the lack of large craters in the valley, is that it is a young feature. However, young is relative..probably it is more than a billion years of age, but less than 3 billion or so (personally, I like the younger number--read on).

Astronomers (planetologists) estimate ages of planetary bodies by counting craters. They assume that planetary bodies gain craters at similar rates throughout the solar system, so if a cratered area is cratered similarly to an area on our moon then that cratered terrain is the same age (the chronology of cratering of the moon is known to a fair degree) as the surface on that part of the moon.

I think this type of assumption is not universally valid, because Mars, for instance, is much nearer the (so called) asteroid belt, and would be subject to greater cratering rates than our moon. And, that is the reason I believe Valles Marineris is young by solar system standards.

Interestingly, a science fiction author named Velikovsky wrote a book (which was published as nonfiction) that was entitled Worlds in Collision, or something similar. In the book he refers to a time when Earth and Mars nearly collided. Of course if that were true Earth and Mars would have been badly fractured due to tidal influences. Velikovsky wrote his book in the 1950's (I think), which was before Plate Tectonics was understood fully, and decades before the discovery of a huge rift on Mars. Had Valles Marineris been known at the time he would, of course, had evidence to support his contention. His work was fiction of course, and it is interesting to note he refers to hydrocarbons (from Venus, if memory serves me) but on the very next page the hydrocarbons are referred to as carbohydrates (the two are very different compounds, of course), which he states is the origin of the Biblical manna from heaven.

Anyway..there is no way at present to determine the age of Valles Marineris, but my personal opinion is that it is at the young end of age estimates.

Answer 3

I've heard around 3 to 3.5 billion years. But I'm not too sure how accurate that might be since the Sun is only about 5 billion years old. It's difficult to tell until we actually land there.

Doug