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The moons of Mars explained.
Mars has two moons, Phobos and Deimos.
They are really tiny. How tiny?
Compared to Mars or our own Moon,
pretty tiny.
Although ‘tiny’ is a matter of opinion.
Their surface area is up close to some of the smallest states on Earth,
like Luxembourg and Malta.
Although Phobos and Deimos are in no way lightweight,
in reality, their gravitational pull isn't even strong enough
to bring them into spherical form.
So they look more like huge potatoes than moons.
The most popular theory of their origin
is that they were once part of the asteroid belt,
until Jupiter's massive gravity kicked them out of it,
so Mars could catch them.
Phobos orbits Mars at a average distance of 9,400 kilometres, once every 7½ hours.
It's on a collision course, and gets 2 metres closer to Mars every year.
In 50 to 100 million years, it will either be ripped to pieces by Mars’ gravity
and be transformed into a beautiful ring,
or it will crash into Mars.
The energy released in this collision would kill everything on the small planet.
So, if there are humans on Mars by then, they should build very strong bunkers.
Smaller Deimos, on the other hand, is slowly escaping Mars.
Eventually, it will fly off into space and leave a lonely red planet behind.
So, in a few hundred million years, Mars will be moonless and on its own.
Unless it manages to catch itself another asteroid.
Subtitles by the Amara.org community


The Moons of Mars Explained -- Phobos & Deimos MM#2

2319 タグ追加 保存
Jimmy Lin 2015 年 7 月 16 日 に公開
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