00:00Look at this stone. At first glance, it looks like one of those ordinary pebbles that you can see when you walk on the beach.
00:08It is not particularly colorful, nor particularly heavy, about 2 kg.
00:13But if I told you that this stone was born on Mars, that it traveled to Earth to finally arrive in Antarctica.
00:20Ah, now the story is much more fascinating. So, let's discover all this.
00:26The researcher Roberta Skor, who worked on the project ANSMET, or Antarctic Search for Meteorites, of the Denver Antarctic Program,
00:34found the meteorite in 1984.
00:37If you want to decipher the name of this space traveler, I can help you.
00:41First of all, this is the place where it was found. The hills of Alan in Antarctica, or Alan Hills.
00:48Then, we have the year of its discovery and the number of the sample.
00:52If you tell yourself that our friend Roberta picked up this stone by exclaiming,
00:56Wow, a piece of Mars, you will be disappointed.
00:59At first, it was totally impossible to know where the meteorite came from.
01:03And something was even more disturbing for the researchers.
01:06This stone was very different from other types of meteorites found on our planet.
01:11Okay, but how did they finally discover that it came from Mars?
01:16Thanks to gas traces similar to those that make up the atmosphere of the red planet.
01:21We learned about its composition thanks to the brave Viking Lander,
01:25who carried out the necessary analyses in situ in 1976.
01:30But let's go back to our discovery. It is very special.
01:34And not only because it comes from far away.
01:37Among the few thousand meteorites found on Earth, only about a hundred probably come from Mars.
01:44And even with that, our little one is different from the others, and seems to be part of a separate group.
01:50So let's go back to the past, and retrace the story of this cosmic traveler.
01:55It probably formed about 4 billion years ago on its native red planet.
02:00One day, which was not very different from the others, the life of this peaceful pebble was upset.
02:06A meteor impact catapulted it into space.
02:09And our stone began its journey as a small asteroid.
02:12At the time, it was much larger than at the time of its discovery on Earth.
02:16At one point, it approached the Earth, and it looks like it decided to explore the places.
02:22This is how, 13,000 years ago, ALH ended its space travel by colliding with our planet.
02:29At present, this Martian fragment is the oldest we have ever found.
02:34But at first, it was not very popular.
02:36It was only in 1996 that its notoriety suddenly increased, following a revolutionary discovery.
02:43NASA researchers have indeed wondered.
02:46This fragment is obviously very old.
02:49But could it have recorded traces of life that could have prospered on Mars at the time when ALH was still attached to the red planet?
02:57And guess what?
02:58It was a very good question.
03:00They detected traces of very fine magnetic particles.
03:04Their structure and chemical composition are quite similar to those of the particles found on our planet.
03:10They are called fossil magnetos.
03:12And it is magnetotactic bacteria that produce them.
03:15This could mean that there were, at some point, life forms on Mars.
03:19In April 2020, Japanese space agency scientists made another discovery.
03:25They detected in our meteorite nitrogen containing organic materials of Martian origin.
03:31So who knows what new surprising secrets a more in-depth examination of the meteorite could reveal to us?
03:37For now, all you have to do is go to Antarctica and start digging.
03:42Indeed, it is an ideal place for meteorite hunting.
03:46We have found nearly 50,000 meteorites in Antarctica, and hundreds of thousands are still waiting to be discovered.
03:53Each of these space rocks can tell us a story about the evolution of the solar system.
03:58For example, the very first lunar rock found on the frozen and desert continent
04:03confirmed the fact that pieces of space objects larger than asteroids could be found on Earth.
04:08Let's imagine that you are inspired and that you decide to go hunting for meteorites in Antarctica.
04:14Get ready to take on serious challenges.
04:17Despite their potential abundance, finding space rocks is not as easy as it seems.
04:23You will have to go to remote areas, and it is not even certain that you can find anything.
04:29It is also a very big problem. Meteorites are disappearing.
04:35Currently, scientists find about 1,000 meteorites a year in Antarctica.
04:40But according to a new study, about 5,000 meteorites would disappear every year.
04:45The cause is rising temperatures.
04:48Worried, researchers have created a model capable of helping them determine where these meteorites are likely to rise to the surface.
04:56This model is quite complex, because it takes into account the snow cover,
05:01the surface temperature, the speed of ice melting, and even the inclination of the terrain.
05:07Scientists then carried out simulations in the context of different warming scenarios.
05:13And it turned out that the meteorites were actually sinking as the temperatures increased.
05:19The surprise of the researchers is obvious.
05:21They did not expect that climate change would affect their work so much.
05:26Even if these regions are below freezing point,
05:29our way of life contributes to the destruction of a crucial archive of the solar system.
05:34But let's go back to your hunt for meteorites.
05:37If you want to increase your chances of finding one,
05:40go to the foot of the mountains where the ice, which usually flows down, is forced to rise.
05:46And do not forget to bring your windbreaker.
05:48In these places, powerful winds sweep the snow exposing a blue ice.
05:53Instead of melting, this old ice can directly turn into water vapor.
05:58And this is how we can discover meteorites that otherwise would remain hidden.
06:03But we must hurry.
06:05Meteorites on the surface disappear quickly.
06:09Even when the temperatures are much lower than freezing point,
06:13the rocks can still absorb some of the heat of the sun and melt the ice.
06:18It is as if they were creating underground tunnels or underglaciers,
06:22sinking and collapsing in front of everyone.
06:25Some time later, the ice closed the entrances of these tunnels,
06:29imprisoning the meteorites and making any discovery impossible.
06:34Scientists admit that it is very difficult to find effective methods to locate meteorites.
06:40And if we do not hurry to develop good techniques,
06:44we risk losing between 80,000 and 250,000 space rocks in total.
06:50It is therefore not surprising that scientists have given themselves the mission to find more meteorites.
06:56They focus on the collapse zones.
06:59These are places where meteorites accumulate on the surface
07:02due to the geological characteristics of the ice flow and climatic conditions.
07:08As you already know, you can find meteorites on blue ice without snow cover.
07:14Meteorites are therefore easy to locate.
07:17But finding these hot spots is often pure chance.
07:20Or you have to spend whole days peeling maps and satellite images
07:25to try to locate the blue ice zones near the research stations.
07:30Let me introduce you to Véronika Tolénar, training glaciologist and her team.
07:36They went faster by developing an intelligent map of Antarctica.
07:41To do this, they used automatic learning and satellite data from NASA,
07:46the Canadian Space Agency and other organizations.
07:49This map highlights the areas where meteorites could be hidden.
07:54On the basis of previous discoveries and all kinds of data related to climate and ice.
08:00Apparently, the best places to find meteorites are on the shores of the continent
08:05and near the mountains covered with blue ice.
08:08Unfortunately, there is not only blue ice that matters.
08:11The temperature and the speed of ice flow are also very important.
08:16For example, if the ice flows too fast,
08:19meteorites are carried away before they can accumulate.
08:23If you want to find a meteorite, you need very precise conditions.
08:27The surface temperature must remain below minus 9 degrees Celsius almost all the time.
08:32Otherwise, the meteorites flow.
08:35You can start looking near the hills of Alan.
08:38Yes, this is where our friend ALH was discovered.
08:41This region is a kind of gold mine for meteorites, with more than a thousand discoveries.
08:46But there are even more promising places,
08:49like the mountains of Fimbulaymen, where no one has done research yet.
08:53You may be the first.
08:56Anyway, thanks to this new map,
08:59researchers have developed a ranking of the best places to hunt for meteorites,
09:03which will better target future outings on the ground.
09:07And as many regions of blue ice are still unexplored,
09:10there are tons of meteorites waiting for you to be discovered.
09:14So, what are you waiting for?
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