The Moon is moving away from the Earth and it could have consequences, according to scientists
Is the moon leaving us?
If so, it's doing it at a very steady
pace. Thanks to a small device installed during the Apollo missions, we are
able to calculate the precise distance between the Earth and its natural satellite. And according to
the measurements, the Moon is slowly but surely moving away from us every year.
3.8 Centimetres
Per Year
On 21 July 1969, the astronauts of the Apollo 11 mission
arrived on the Moon, taking a small step for man, but a big one for mankind.
But there was nothing touristy about this mission! On the spot, the scientists
carried out various tasks, collecting rock and lunar soil, examining the
surface and installing a lunar reflector.
The
tides are to blame
So
what is the reason for this? According to the Cite de l'Espace in
Toulouse, this slow separation is caused by the dynamics of
the tides. In an article published on its website
Due to its gravitational pull, the Moon attracts the seas and
oceans towards it, causing the tides (the Sun also plays a role) This
deformation of our planet along the Earth-Moon axis results in friction and
therefore in the dissipation of energy in the form of heat, which has
consequences on the orbital balances of the two bodies
Evidence
set in stone
More
recently, a study has looked at this distance and its effects. But the team in
charge of this study did not need to go to the Moon. They were able to carry out their analyses directly on Earth,
by observing its ancient sedimentary layers. Published in PNAS,
the results of their work are not easy to digest for a layman in science,
but it is important to understand that the distance between the Earth and the
Moon can have consequences on the climate, and thus alter the colours of the
sediments.
So the scientists went to Karijini
National Park in Australia, where there are
rocks that are 2.5 billion years old. And indeed, Australian
rocks did show some alterations.
Periodic changes in the shape of the Earth's orbit and the
orientation of its axis influence the distribution of sunlight received by the
Earth over periods of several years.
Rest assured, however, that while this distance is real, it
is virtually inconsequential for us. Although, in 600 million years, our natural satellite should
be so far away that it will no longer be able to eclipse the Sun. Anyway, that gives us plenty of time to find a solution to
this problem.