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Découvrez pourquoi l'Antarctique est l'endroit idéal pour dénicher des météorites rares et précieux. Entre glace immaculée et températures glaciales, ce continent recèle des secrets fascinants sur notre système solaire, tout en offrant un environnement parfait pour préserver ces roches spatiales. Une aventure glaciale pleine de découvertes étonnantes !

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00:00Look at this stone.
00:01At first, it has all the air of one of these ordinary stones
00:04that you can see when you walk on the beach.
00:07It is not particularly color,
00:09nor particularly heavy,
00:11about 2 kg.
00:13But if I tell you that this stone is on Mars,
00:15that it has traveled to the Earth
00:17to finally arrive in Antarctica...
00:19Ah, now the story is much more fascinating.
00:23So, discover all this.
00:25The researcher Roberta Skor,
00:27who worked on the project ANSMET
00:29or Antarctic Search for Meteorites
00:32of the Denver Antarctic Program,
00:33found the meteorite in 1984.
00:37If you want to know the name of this space traveler,
00:40I can help you.
00:41First, it is the place where it had been found.
00:44The island of Allan in Antarctica
00:45or Allan Hills.
00:47Then, we have the year of its discovery
00:49and the number of the screen.
00:51If you tell us that our friend Roberta
00:53saw this stone in exclaiming
00:55Wow, a piece of Mars!
00:57You will be surprised.
00:59At first, it was totally impossible
01:01to know where the meteorite came from.
01:03And something even more trouble the researchers.
01:06This stone was very different
01:07from the other types of meteorites
01:09found on our planet.
01:11Ok, but how did they finally discover
01:14that it came from Mars?
01:15Grâce to the traces of gas
01:17similar to those that compose
01:18the atmosphere of the red planet.
01:20We knew his composition
01:23thanks to the courageous Viking Lander
01:25who did the analysis necessary in situ
01:27in 1976.
01:30But we come back to our discovery.
01:32It is very particular.
01:34And not only because it comes from very far.
01:36Among the few thousand
01:38meteorites found on Earth,
01:40only a hundred percent
01:42probably come from Mars.
01:43And even with that,
01:44our little is different from others
01:46and seems to be part of a separate group.
01:49Let's go into the past
01:51and retrace the history
01:52of this cosmic voyage.
01:54She was apparently formed
01:56there about 4 billion years
01:58on her native red planet.
02:00One day,
02:01which was not yet very different from others,
02:03the life of this peaceful caillou
02:04was discovered.
02:06A meteorite impact
02:07the catapulted into space.
02:09And our pierre
02:09started its voyage
02:10of small asteroids.
02:12At the time,
02:13she was much bigger
02:14than the moment of her discovery
02:15on Earth.
02:16At a moment,
02:17she approached Earth
02:18and we would say
02:19that she decided
02:20to explore the places.
02:21It's like that
02:2213,000 years ago,
02:23ALH ended up
02:25her space voyage
02:26in a collision
02:27with our planet.
02:29At the moment,
02:29this Martian fragment
02:31is the most ancient
02:31that we had ever found.
02:33But at the beginning,
02:34it was not very popular.
02:36It was only in 1996
02:38that its notoriety
02:39was suddenly accrue
02:40after a revolutionary discovery.
02:43The researchers
02:44of the NASA
02:44were asked.
02:46This fragment
02:47is very ancient.
02:49But could they have
02:49recorded
02:50traces of life
02:51that would have been
02:52prospered on Mars
02:53at the time
02:54where ALH
02:54was still attached
02:55to the red planet?
02:57It was a very good question.
03:00They detected
03:01traces of very fine
03:02particles of magnetite.
03:04Their structure
03:04and their composition
03:05are very similar
03:07to the particles
03:08that we find
03:09on our planet.
03:10We call them
03:11magnétophossiles.
03:12And these are
03:13magnétotactical bacteria
03:14that produce them.
03:15This could therefore
03:16mean that
03:16there were, at a moment
03:17at a moment,
03:18forms of life on Mars.
03:19In April 2020,
03:21scientists
03:21from the Japanese Space Agency
03:23have made another
03:24discovery.
03:25They detected
03:26in our ozone meteorite
03:27containing
03:28organic materials
03:29from Martian origin.
03:31So, who knows
03:32what new
03:33secret
03:33an extraordinary
03:34examination
03:35of the meteorite
03:36could reveal us
03:37that
03:37for the time,
03:38there is no longer
03:39you have to go back
03:39to Antarctica
03:40and put you down.
03:42In fact,
03:43it is an ideal place
03:44for the hunting
03:45meteorites.
03:46We have found
03:47nearly 50,000 meteorites
03:49in Antarctica
03:49and hundreds of thousands
03:51of thousands
03:51are still waiting for
03:52to be discovered.
03:53Each of these
03:54space rocks
03:54can tell us
03:56a story of the evolution
03:57of the solar system.
03:58For example,
03:59the first moon
04:00found on the glacier
04:01and desert
04:02a confirmed
04:03the fact that
04:04we could find
04:04on Earth
04:05more large
04:07than asteroids.
04:08Imagine
04:09that you are inspired
04:10and that you decide
04:11to go to the
04:12hunting meteorites
04:13in Antarctica.
04:14Prepare-vous
04:15to raise
04:16serious challenges.
04:17Despite their
04:18abundance,
04:19finding space
04:20is not as easy
04:22as it seems.
04:23You should have
04:23to go back
04:24and it is not even
04:26certain
04:26that you can find
04:27anything else.
04:28It is also
04:29a very big problem.
04:31The meteorites are
04:32disappearing.
04:34Currently,
04:36find about
04:371,000 meteorites
04:38per year
04:38in Antarctica.
04:40But according
04:40to a new study,
04:42about 5,000 meteorites
04:43disappear every year.
04:45In cause,
04:46the increase
04:46of temperatures.
04:48Inquiet,
04:49researchers have created
04:50a model capable
04:51to help them
04:51determine where
04:52these meteorites
04:53are susceptible
04:54to go to the surface.
04:56This model is quite
04:57complex,
04:58because it takes
04:59into account
04:59the temperature
05:01of the surface
05:02temperature,
05:02the speed of the ice
05:04and even
05:05the inclination
05:06of the terrain.
05:07The scientists
05:08have then implemented
05:09simulations
05:10in the cadre
05:10of different
05:11scenarios of
05:12warming.
05:12And it is revealed
05:13that the meteorites
05:14were effectively
05:15as soon as
05:16the temperatures
05:17increased.
05:18The surprise
05:19of the researchers
05:19is evident.
05:21They did not
05:24to work.
05:25Even if these regions
05:26are below
05:27the point of
05:28freezing,
05:28our mode of life
05:29participates
05:30to the destruction
05:31of a crucial archive
05:32of the solar system.
05:34But revenons
05:35to your chase
05:36to the meteorites.
05:37If you want to increase
05:38your chances
05:39to find one,
05:40rendez-vous
05:40on the feet
05:41of the mountains
05:41where the ice
05:42which usually goes
05:43to the bottom
05:44is forced to go.
05:46And don't forget
05:47to take your
05:48wind.
05:48In these places,
05:50there are powerful
05:50clouds
05:50of the snow
05:51and expose
05:52a blue blue
05:53vif.
05:53Instead of
05:54sinking,
05:54this ancient glass
05:55can directly
05:56transform in
05:57vapor
05:57and it is
05:58so that we can
05:59discover the meteorites
06:00who, otherwise,
06:01remain hidden.
06:03But you have to be careful.
06:05The meteorites
06:06at the surface
06:07disappear quickly.
06:08Even when
06:09the temperatures
06:10are slightly inferior
06:11to the point
06:11of the congelation,
06:13the meteorites
06:13can still absorb
06:14a part of the sun
06:15of the sun
06:16and make the ice
06:18It's like if they
06:19created
06:19underground tunnels
06:20or glaciers
06:22sinking and
06:23dropping
06:23to the view
06:24of all.
06:25A few months later,
06:27the meteorites
06:27close the entrance
06:28of these tunnels,
06:29imprisoning the meteorites
06:31and making
06:31all the discovery
06:32impossible.
06:35Scientists admit
06:36that it is very difficult
06:37to find
06:38effective methods
06:38to see
06:39the meteorites.
06:41And if
06:41we don't worry
06:42about putting
06:42good techniques,
06:44we risk
06:45to lose
06:45between 80
06:46and 250
06:47thousand
06:48rocks,
06:48in total.
06:50So it's not surprising
06:51that scientists
06:52were given
06:53for mission
06:54to find more
06:55meteorites.
06:56They focus on
06:57the zones
06:58of air.
06:59It's a place
07:00where the meteorites
07:01accumulate
07:01to the surface
07:02due to the geological
07:04of the ice
07:05and the climate conditions.
07:08As you already know,
07:10you can find
07:11meteorites
07:11on the blue
07:12without
07:13coverts
07:13neigeuses.
07:14The meteorites
07:15are so easy
07:15to see.
07:16But finding
07:17these hot points
07:18often
07:18is often
07:19pure
07:19hasard.
07:20Or,
07:20you have to spend
07:21the whole day
07:22and satellite images
07:24to try to see
07:26the blue zones
07:27located near
07:28the research stations.
07:30Let me introduce
07:32Veronica Tollenaar,
07:33glaciologist
07:34and her team.
07:36They went to the
07:37higher speed
07:38by creating
07:39a smart card
07:40of Antarctica.
07:41To do it,
07:42they have access
07:43to the automatic
07:44and the satellite data
07:45of the NASA,
07:46the Canadian Space Agency
07:47and other organizations.
07:49This card
07:50put in evidence
07:51the zones
07:51where meteorites
07:52could be hidden
07:54on the basis
07:54of previous discoveries
07:55and all sorts
07:56of data
07:57relative to the climate
07:58and the ice.
08:00Apparently,
08:01the best place
08:01to find meteorites
08:03is located
08:03on the continent
08:04and near the mountains
08:06covered with blue glass.
08:08Unfortunately,
08:09there is not only
08:09the blue glass
08:10which counts.
08:11The temperature
08:12and the speed of the glass
08:14are also very important.
08:16For example,
08:17if the glass
08:17too quickly
08:18the meteorites
08:19are emptied
08:20before being accumulated.
08:22If you want to find
08:24a meteorite,
08:24you need so
08:25very precise conditions.
08:27The surface
08:28should be inferior
08:29to minus 9 degrees Celsius
08:30almost all the time.
08:31Otherwise,
08:32the meteorites
08:33coulent.
08:34You can start searching
08:36près des collines
08:37d'Alan.
08:37Yes,
08:38that's where our friend
08:38A.L.H.
08:39was discovered.
08:40This region
08:41is a sort
08:42of a mine
08:42for meteorites
08:44with more than 1000
08:45discoveries.
08:46But there are
08:46even more prominent places
08:48like the mountains
08:49of Fimbulheimen
08:50where no one
08:51has ever done research.
08:53You may be the first.
08:56You may be the first.
08:57With this new card,
08:58the researchers
08:59have put on the point
09:00a classification
09:00of the best places
09:01for the meteorites
09:03which will help
09:04better target
09:04the future
09:05on the ground.
09:07And as many
09:07blue clouds
09:08are still inexploration,
09:10there are tons
09:11of meteorites
09:11waiting for you
09:12to be discovered.
09:14So,
09:14what do you expect?
09:15Bye,
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