00:00NASA has created a super rover called Curiosity
00:04and sent it to Mars to discover everything the red planet has to offer
00:08because it may become our next home.
00:12Curiosity explores the surface of Mars,
00:15takes measurements and collects data for more than 10 years, 2011.
00:20And this good old Curiosity fell on interesting rocks
00:23crushed by the waves in a region of the Martian surface
00:26that was thought to be much more arid.
00:29Scientists think that this area was in fact the bed of a lake.
00:34It could indeed be the bottom of a dried up lake
00:37with all the sediments and other elements that have accumulated there.
00:41All this can give us important clues about the history of the lake.
00:45For example, the types of organisms that were able to live there,
00:49its depth, its lifetime, etc.
00:53These striated patterns formed by the waves
00:56indicate that these rocks were able to form at a time
00:59when strong winds were blowing strongly on the waters of this ancient lake.
01:04Do you know this particular sound you hear when you wear a shell on your ear?
01:09It is due to the way the air is trapped inside the shell
01:13and its friction against the walls of it.
01:16The air unable to escape, it vibrates at frequencies
01:19that depend on the size of the shell.
01:22And yes, you have the impression of hearing the sound of the waves
01:26crashing on a shoreline.
01:28And now I imagine Mars,
01:30a place where we can still hear the sound of the waves
01:33hitting the shores of huge mysterious lakes
01:36that have disappeared for a long time.
01:39During its mission,
01:41Curiosity also encountered a metallic object
01:44that turned out to be a meteorite.
01:47This strange rock from space
01:49is made up of nickel and iron.
01:52It is called Kakao.
01:54It is the size of a small car, 2 meters long,
01:57and weighs more than a ton.
02:00This is an important discovery,
02:02because it is rare to find metallic objects on the surface of Mars.
02:06Most of the rocks are made up of basalt
02:09or other volcanic materials.
02:12This piece of metal could therefore teach us more about the history of Mars
02:16and how the planet was formed.
02:19In addition, it is quite remarkable.
02:22The surface of Mars is red because of the oxides,
02:25while Kakao has a dark gray metallic appearance.
02:28It is also rounded and smooth,
02:30which means that it has crossed the atmosphere of Mars.
02:33Other robots have explored Mars.
02:36For example, the Mars Reconnaissance Orbiter, or MRO,
02:40of NASA, discovered circular sand dunes.
02:44Sand dunes are very common on the red planet.
02:47They appear in different shapes and sizes.
02:50But these circular dunes are much rarer.
02:54They are made up of dark sand
02:57and are surrounded by lighter materials.
03:00What is interesting
03:02is that they are arranged according to a specific pattern,
03:05like the rays of a wheel.
03:08This could be due to the way the winds blow at this place.
03:12But let's go back to our friend Curiosity.
03:15It has discovered many other interesting things,
03:18such as oxygen levels in the atmosphere of the planet, for example.
03:22The levels change depending on the seasons.
03:25There is more oxygen in spring and summer.
03:28We do not yet know why.
03:30But of course, these levels are still insufficient for us to breathe on Mars.
03:34The oxygen concentration there is 0.1%,
03:37which is about 100 times less than in the Earth's atmosphere.
03:41The atmosphere of Mars is mainly composed of carbon dioxide,
03:45with traces of other gases.
03:48Curiosity has also decided to analyze the age of the discovered rocks.
03:52And it seems that they are much older than we thought.
03:57Some date back more than 3 billion years.
04:00Our rover has also found organic molecules in soil samples.
04:05These molecules are in fact the constitutive elements of life.
04:09This does not prove that there is actually life on Mars.
04:12It is simply one of the elements that suggests
04:15that there could have been a form of life there a long time ago.
04:19Curiosity has uncovered potential evidence
04:22of the existence of a large reservoir of liquid water under the southern polar cap.
04:27Probably very salty and filled with different minerals.
04:31This high salinity is the reason why this water
04:34could remain liquid at much lower temperatures at the freezing point.
04:38It would be nice to have an underground ocean in which to swim,
04:42especially when these crazy Martian winds are raging on the surface.
04:47And it would be great to have something that would protect us
04:50from the levels of radiation emitted on the red planet.
04:54Martian soil contains chemicals and toxic salts
04:58that can be very harmful to humans.
05:01Astronauts could be exposed to these toxic substances,
05:06either by direct contact with the ground
05:09or by inhaling dust containing these salts.
05:12In addition, these substances could pose a problem for cultures.
05:17This is a very important discovery for future missions on Mars,
05:21because astronauts will have to be able to grow their own food to survive.
05:27Another element favorable to the idea of a potential life on Mars
05:31is the discovery of methane.
05:33Methane is a very important discovery because,
05:36usually, it is the living organisms that produce it.
05:40Without them, where could it come from?
05:44In reality, there are several possible explanations.
05:48For example, there is the geological activity of underground reservoirs.
05:52Another idea is that meteorites would have brought this methane to the red planet.
05:57Interestingly, the levels of methane are higher in certain areas.
06:02I do not know what it is for you,
06:04but I like the theory that methane would come from living organisms.
06:09It is possible that the volcanoes of Mars are still active.
06:13We know that there are many volcanoes extinguished on the red planet,
06:17but we have never found enough evidence
06:20to affirm that some of them are still alive.
06:24Scientists have studied volcanic deposits
06:27and have discovered that some volcanoes could have erupted about 5,000 years ago.
06:32Previously, everyone thought that the last eruption
06:35occurred 3 to 4 billion years ago.
06:38If we could compress the geological history of Mars in a single day,
06:43it would be equivalent to an eruption that occurred a second ago.
06:47So, we never know.
06:49The magma is still boiling secretly under the Martian surface.
06:53Future generations coming to build colonies there would really have fun.
06:59But Mars is a cold and sterile place on which life is no longer possible.
07:03And one of the main reasons is the loss of its atmosphere.
07:07The red planet used to have a much thicker atmosphere,
07:11similar to that of Earth.
07:13This phenomenon is largely explained by the relative weakness of its magnetic field.
07:18The Earth's magnetic field protects our atmosphere from solar wind,
07:22a flow of charged particles from our beautiful star.
07:26Without a powerful magnetic field,
07:29Mars could not protect itself from this devastating force
07:32which ended up taking up most of its atmosphere.
07:36Another factor that played an important role in the loss of Mars' atmosphere
07:40is its relatively low gravity.
07:43Mars' gravity being lower than Earth's,
07:46gas molecules escape more easily into space.
07:50Mars was therefore quite close to our planet at a certain time.
07:54But with its thin atmosphere, it cannot keep the heat,
07:58which makes it very cold and very difficult to explore for us.
08:03But it may be a good thing that we did not have the opportunity
08:06to visit the red planet at its beautiful time.
08:09It is said that a huge flood would have taken place there.
08:13Yes, Mars was probably more humid and more hospitable than it is today.
08:19With beautiful rivers and magnificent lakes,
08:22springs and other springs of water.
08:25Some research has also highlighted the existence of large canals
08:29dug at the surface of the planet.
08:32These canals are much larger than all those we have been able to discover in the past.
08:36It is suggested that this great flood occurred billions of years ago.
08:41It may have been caused by different phenomena,
08:44such as volcanic activity,
08:46melting of glaciers,
08:48and the release of carbon dioxide by terrestrial crust.
08:52This flood may even have created temporary water expanses.
08:56Let's hope that we will find more clues about the presence of microbial life traces.
09:01It would still be nice.
Comments