Mars' Moon Phobos Is Slowly Being Ripped Apart By Gravity Says NASA Researchers

11/11/2015 09:45 | Updated 11 November 2015

NASA researchers have come to the conclusion that Phobos, Mars' largest moon, is slowly but surely being ripped apart.


How? Tidal energy, the same forces that can get you stranded on a beach and result in the phenomenon known as a 'supermoon'.

For Phobos though, these tidal forces have nothing to do with water and ultimately they're a whole lot deadlier.


Travelling at just 3,700 miles above Mars' surface Phobos is the closest moon to any planet in the solar system and it's getting closer every day.

In a spectacular 'tug of war' Phobos and Mars are battling against each other's gravitational pull. Mars is winning the fight however, and it's winning it by a country mile.

Phobos is descending towards the planet's surface at a rate of over 6 feet every 100 years. Now that may not sound like much but when you consider it's 11km in diameter you begin to realise the enormously powerful forces at play.

Terry Hurford and his colleagues at NASA’s Goddard Space Flight Center made the discovery after studying the enormous 'stretch marks' that scar the surface of the moon.

Originally believed to be the ripples of a giant asteroid impact, scientists now believe the stretch marks are in fact caused by the enormous gravitational pull of Mars itself, essentially pulling Phobos apart.


Phobos is the closest moon to any planet in our solar system.

So how long does Phobos have? Scientists suggest that Phobos will eventually be destroyed in around 30-40 million years, a long time for humans but a blink of the eye for our solar system.

It was originally thought that Phobos' structural composition was too thick to be so drastically affected by Mars however recent thinking has changed in favour of a more fractured body structure.

Hurford and his team believe that Phobos is in fact a collection of 'glued together' rubbly particles which would go some way to explaining why Mars is able to have such a significant impact on the moon.

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