A new research has thrown fresh insight into the tiny moons of Mars — Phobos and Deimos — with regard to their origin and the supposed ring-like structure of Mars in the past just like Saturn.
A NASA-funded study by scholars at the Purdue University claimed that Mars will regain the rings when one of the moons disintegrates.
According to a new model offered in the study, Purdue scholar Andrew Hesselbrock said the debris strewn into space from an asteroid collision with Mars, around 4.3 billion years ago, has been the starting point of moon formation in the Red Planet.
Hesselbrock's simulations concluded that Mar's moons were actually remnants of a bigger moon that broke away millions of years ago.
Big Moon Splinters Into Ring
Formation of the big moon was caused by a gigantic impact experienced by Mars billions of years ago. Though it led to the formation of a giant moon, it was unstable and splintered into a larger ring.
It also kickstarted the cycle of spatial residue alternating between two structures — a planetary ring and a moon form resulting from the clumping.
"My argument is that Phobos ... was not produced in an impact," said study author Hesselbrock.
To buttress their theory of impact on Mars surface, the authors point to the large Borealis Basin on Mars surface, covering a broad swath of the ejected debris into space.
The study has been published in Nature.
Ring Formation And After
The researcher's model also suggests that small moon formation from the ring was also accompanied by the drifting of the planet to form the moon. When rings coalesce to form smaller moons, the remaining residue is thrown into Mars surface or pushed into space.
The exercise is a recurring one, with small moons breaking into rings and later clumping into moons.
In another parallel process, the moon also edges toward Mars under the pull of gravity. The drift will culminate when it hits the Roche limit as tidal forces of Mars turn intense enough to rip apart the celestial body.
Phobos Facing Disintegration
According to the model, Phobos is now going closer to Mars, and it may break apart when it reaches the nadir of Roche limit. New rings will be due in a span of millions of years.
In the past also, based on the intensity of Roche limit, the cycle might have played out several times in the billions of years that has passed.
What is interesting is that the moon, when it takes rebirth from a ring, would diminish in size at least five times the previous size. The debris falling on Mars is in evidence at the sedimentary deposits seen at the equator of Mars.
"You could have had kilometer-thick piles of moon sediment raining down on Mars in the early parts of the planet's history, and there are enigmatic sedimentary deposits on Mars with no explanation as to how they got there," coauthor David Minton said.
Deimos Is Safe
Unlike the disintegration threat faced by Phobos, the other moon Deimos is safe, as it too far to be a part of the regenerative cycle.
Being too far means the effects of Martian tidal forces will not affect its orbit, and it will keep increasing the distance from Mars.
The Purdue model is good at the simulation stage and is yet to be proved, though it remains a big possibility. To verify the model against the moons' origin, the way out is collecting samples from the moons and Mars for an analysis. If they match, Hesselbrock's theory may come true.
