- 2 hours ago
Scientists have reported a stunning discovery on the Moon’s surface — objects that appear strikingly similar to bones. The unexpected find has left researchers searching for explanations, as nothing like this was ever thought possible beyond Earth. Now, the discovery is raising new questions about what we truly know about the Moon and its past.
Category
😹
FunTranscript
00:01Soon we might start constructing loads of stuff on the Moon.
00:07All because India's Moon mission has recently detected sulfur near the Moon's South Pole.
00:14This chemical element can come in extremely handy for creating infrastructure on our satellite.
00:21It's the first time this chemical element has been discovered on Earth's natural satellite.
00:25This sought-after element is mostly found near Earth's volcanoes.
00:31Its appearance on the Moon speaks volumes about the satellite's volcanic history and its past atmospheric conditions.
00:40The mission's rover detected this chemical element less than a week after touching down around 70 degrees from the Moon's
00:47South Pole on the 23rd of August, 2023.
00:52This historic landing on the lunar surface made India the fourth country to safely land a mission on the Moon.
01:00It's also the first spacecraft to touch down so close to the South Pole of our satellite.
01:05It's an area of strategic importance because it's believed to be home to deposits of water ice.
01:13If it turns out to be true, future missions might be able to harvest it and turn this water ice
01:18into drinking water or even rocket fuel.
01:23For two weeks, the lander carried out the data collection, mainly focused on the analysis of the Moon's soil and
01:29its extremely thin atmosphere.
01:32Meanwhile, the solar-powered Pragyan rover started its quest to find frozen water on the Moon.
01:39As for the lander, it demonstrated another amazing feat on the 3rd of September.
01:44The spacecraft fired up its engines and lifted itself for about 16 inches into the air.
01:50Then it made a tiny hop to land 12 to 16 inches away from its original position.
01:56It's kinda a big deal.
01:59Being able to get a lander back off the surface of the Moon is essentially for future missions,
02:04showing that they can safely return soil samples or even astronauts back home after a lunar mission.
02:12In September, the Indian spacecraft was put into sleeping mode.
02:17The 14-day-long lunar night was approaching,
02:20and the spacecraft wasn't designed to collect scientific data during this period of time.
02:26So far, we've learned about a few major findings of the mission.
02:30One is related to measuring the temperature of the Moon's topsoil at different depths.
02:36Intriguingly, the surface of the satellite in that region turned out to be hotter than expected.
02:42It was believed that the temperature could be between 68 and 86 degrees Fahrenheit on the surface.
02:49But it was around 158 degrees Fahrenheit, way hotter than it should be.
02:55The other discovery indicates the presence of several chemical elements, including oxygen.
03:01Besides, the data received from the spacecraft confirms the presence of aluminum, calcium, iron, titanium, silicon,
03:11and other chemical elements on the lunar surface close to the South Pole.
03:15The rover also used special instruments designed to measure quakes and rumbles beneath the lunar surface to detect some seismic
03:24activity.
03:25It brings us back to the sulfur detected thanks to the rover's spectroscope.
03:32Scientists are currently working on figuring out whether this element formed on the surface in a natural way,
03:38or whether it's the result of volcanic activity or a meteor strike.
03:44Another astonishing thing found on the Moon is a rock, and it may be the oldest known Earth rock.
03:50A 0.7 inch wide chip included in a large rock collection brought to our planet by Apollo astronauts might
03:58actually be a 4 billion year old fragment of Earth.
04:04This finding could help us paint a better picture of the intense pounding early Earth got at the dawn of
04:10its life.
04:12It could go like this.
04:14Soon after the rock formed, an asteroid impact might have blasted it from Earth.
04:19At that time, our planet's satellite was three times closer to Earth than it is today.
04:25The collision was so powerful that this chunk of terrestrial rock found its way to the Moon.
04:31Later, this fragment got engulfed in a lunar breccia, a motley kind of rock.
04:37Eventually, the rock was brought back home to Earth by Apollo 14 astronauts.
04:42Even though scientists had found meteorites coming from Mars and the Moon before,
04:47it was the first time a rock from the Moon turned out to be a terrestrial meteorite.
04:52They also found out that the rock had formed in a water-rich environment at temperatures and pressures,
04:58corresponding to those at around 12 miles beneath the surface of our planet.
05:05In 2019, China's Chang'e-4 mission made history by landing on the far side of the Moon.
05:12The mission's rover helped researchers visualize structures hidden deep below the surface of the satellite,
05:18revealing billions of years of lunar history.
05:22The Yutu-2 rover made this discovery with the help of its lunar penetrating radar.
05:27It imaged deep into the Moon's surface and listened to echoes of sound bouncing back off structures hidden from view
05:35under the surface of the Moon.
05:38It turned out those structures were resting at depths of almost 1,000 feet.
05:44The research suggests that the first 130 feet under the surface are made up of layers of dust, soil, and
05:51rocks.
05:51The instruments also discovered a concealed crater that must have formed after a large object slammed into the Moon's surface.
05:59Long, long ago, ancient lava was likely to be flowing deep underground.
06:06Researchers believe that the broken rocks around the formation might be debris produced by the impact.
06:12They also found that the volcanic rock layers were thinner the closer they were to the surface.
06:18Such a thickness variation of lava flows might mean a decrease in the number and magnitude of eruptions over time.
06:27So, lunar volcanic activity gradually dwindled since the Moon's formation around 4.5 billion years ago.
06:36On the far side of the Moon, there is one of the largest and oldest impact craters in our solar
06:42system, the South Pole-Aitken Basin.
06:46Unfortunately, from Earth, you can only see its outer rim, which looks like a huge chain of mountains.
06:52It's a ginormous 8-mile-deep dent, stretching for more than 1,500 miles in diameter and covering one-fourth
07:01of the Moon's surface.
07:03Astronomers are sure that this crater appeared when an asteroid collided with the Moon around 4 billion years ago.
07:10And now, look at this gigantic chunk of metal the size of four states of Connecticut.
07:16As for its weight in pounds, it's enough to say that the number contains 18 zeros.
07:22This mysterious mass is hidden about 180 miles under the Moon's surface, somewhere in the middle of the South Pole
07:30-Aitken Basin.
07:32It was discovered when GRAIL, which stands for NASA's Gravity Recovery and Interior Laboratory Mission, gathered data about our natural
07:41satellite.
07:42When examining this information, scientists noticed that in one place on the Moon's surface, there was a weird change in
07:49gravity.
07:50After researching this phenomenon, they included that something mysterious was weighing down the basin floor there.
07:58So far, researchers haven't figured out the origin of the bizarre lump, but there are several theories.
08:05One of them claims that the finding is a chunk of dense oxide, which appeared when the Moon was just
08:11taking its shape.
08:12At that time, the satellite was still covered with ancient oceans of magma, and the lump could be formed at
08:18the final stages of its cooling.
08:20However, most scientists support another theory, according to which, the puzzling mass is part of the giant asteroid that once
08:28created the South Pole-Aitken Basin.
08:31Since the thing is metallic, it's probably the iron-nickel core of the asteroid.
08:38There might be a labyrinth of lava tubes on the Moon.
08:41Not so long ago, astronomers received the results of underground topography and discovered a massive cave under the surface of
08:49Earth's satellite.
08:51It could be the result of the lunar volcanic activity that happened more than three billion years ago.
08:58Streams of lava hardened, creating a thick, hard crust on the outside.
09:03But inside, it kept flowing, melting the rock and creating tunnels and caves.
09:10Numerous small pits in the Moon's surface discovered by NASA seem to be the openings to such lava tubes.
09:17If this theory is confirmed, the underground tunnels might serve not only as a convenient location for human-crewed space
09:24missions,
09:25but also as much-needed water sources for astronauts.
09:31You might think high-tech telescopes let us see every inch of the Moon, but that's not true.
09:36At our satellite South Pole lie giant craters untouched by sunlight for eons,
09:42stuck in pitch black, colder than Pluto, and almost impossible to explore.
09:49However, maybe we have to if we want to explore space.
09:52Because the darkness hides some must-have resources that will make life and long-distance travel in space possible.
09:59Yes, we're talking about water locked up as tiny crystals in the lunar soil.
10:06Now, water in space is always good news.
10:09You've probably heard that scientists are also obsessed with finding it on Mars.
10:14If the red planet has any type of water below its surface, it raises the exciting possibility that life might
10:21have existed there.
10:21Even microbes would be the biggest discovery in human history.
10:26That's why rovers are poking around Martian craters and drilling into the soil like some very dedicated space gardeners.
10:34But as incredible as water on Mars would be, water on the Moon might be even more valuable to us
10:41in the short term.
10:41The reasons are simple. The distance and the gravity of the Moon.
10:46We can reach our satellite in three days. That's almost nothing.
10:50It takes at least seven days to reach New York from London via a cruise ship.
10:54But more important than the length of the trip is the possibility of using the Moon as a pit stop.
11:01Stop, refuel, and relaunch so we can resume exploration.
11:06The gravity on the Moon is only one-sixth as strong as Earth's.
11:11That's not just useful for endlessly entertaining yourself by jumping around.
11:15This difference means that launching rockets from our satellite is much easier compared to launching them from Earth,
11:22which requires a tremendous amount of fuel just to break free from the atmosphere.
11:26For example, the Saturn V rocket, which took astronauts to the Moon during the Apollo missions,
11:33was made up of more than 90% fuel just to get off the ground.
11:37On the Moon, however, it's much easier to launch a rocket.
11:41That means that we could carry heavier loads with less fuel.
11:45It's like being able to take a bigger suitcase on your trip.
11:48If we can find and use ice on the Moon to create rocket fuel,
11:52it would turn our satellite into a practical and affordable stop for exploring the solar system.
11:58Not to mention that by applying some basic chemistry,
12:02we could extract oxygen from water and use it for breathing or rocket engines.
12:07Also, astronauts would need water to drink and grow crops on the lunar base.
12:12So, what do we know about the latest discoveries?
12:16For a long time, scientists thought the Moon was completely dry.
12:20But in 2009, NASA basically crashed a rocket into a crater.
12:25It caused an explosion of ice and vapor, like fireworks,
12:29and finally confirmed that the Moon had some kind of water.
12:34But how much?
12:35Well, enough to matter.
12:37The data suggests there could be hundreds of millions of tons of water ice
12:42locked up in the Moon's polar regions.
12:44Some estimates roughly say 1.3 trillion pounds.
12:48That's about the same weight as 460 million cars.
12:53Not exactly lakes, but still a lot.
12:55And there still could be more.
12:58This water could also contribute to uncovering cool scientific secrets.
13:03The ice is ancient, which makes it like a time capsule from the early days of the solar system.
13:09Studying those frozen molecules might tell us not only how water got to the Moon,
13:14but also how it appeared on Earth.
13:18Anyway, what's all that water doing on the Moon?
13:21How did it get there?
13:23Scientists assume that some of it probably hitched a ride on comets and asteroids billions of years ago.
13:29Many of those space rocks carried ice, and some of that water ended up in the polar regions.
13:35Another source could be the way solar wind interacts with the lunar surface.
13:39In any case, however this ice appeared on the Moon, the real trick is where it ended up – inside
13:45its polar craters.
13:47And while we can find the ice not only in the craters at the South Pole, that's where the largest,
13:53most stable reserves are believed to be.
13:55Some of those craters are enormous.
13:58One of the most famous is called the Shackleton Crater, and it's over 13 miles wide and more than 2
14:04miles deep.
14:06That's almost twice as deep as the Grand Canyon.
14:09The Moon barely tilts on its axis, only about 1 degree, so the Sun never peaks over the rims of
14:16those deep polar pits.
14:18The temperatures dip to around negative 400 degrees Fahrenheit there.
14:22Any water or chemicals trapped in that frozen dirt just stay there, locked away like in a freezer.
14:29Something really cool is that at the South Pole, you have parts that are stuck in the perpetual darkness.
14:35But some nearby mountain ridges get almost non-stop sunlight.
14:40Scientists call them the peaks of eternal light.
14:43They are perfect for setting up solar panels, while still being close enough to access the icy treasures hidden below.
14:51The poles of the Moon are the only places in our solar system we know of where perpetual day and
14:57night exist side by side.
14:59But the eternal night isn't just fascinating, it's dangerous.
15:04The terrain out there is absolutely unforgiving.
15:08We can't even simulate something like that on Earth.
15:10We don't even know what it looks like from the inside.
15:14It's worse than exploring the northernmost part of Antarctica while wearing a blindfold.
15:19So now that we know this, is that potential water even obtainable?
15:23That question is probably worth several trillions of dollars.
15:28Yes, there's water over there, but getting to it won't be like scooping ice cream from a bowl.
15:33What we're really talking about are microscopic ice crystals mixed into lunar dust.
15:39To make use of it, machines would need to dig and heat up the soil, then capture the vapor before
15:45it escapes back into space.
15:47And then there's freezing.
15:49Even assuming a human or rover could safely reach the bottom of a crater, it'd be almost impossible to navigate.
15:57Batteries and equipment probably wouldn't last, and it's impossible to use solar panels or electronics down there.
16:03They'd freeze in minutes.
16:05However, NASA's Lunar Reconnaissance Orbiter uses all kinds of radars and sensors to sniff out what the crater looks like
16:12inside.
16:14And now there's an even sharper tool.
16:16Shadow Cam.
16:18A camera so sensitive, it can capture details in light a hundred times dimmer than what our eyes can see.
16:25Basically, the ultimate night vision device.
16:28With it, we can finally map those pits without even setting foot there.
16:33That's why engineers are thinking up all sorts of clever solutions.
16:38Some concepts involve nuclear-powered rovers with headlights strong enough to carve through the dark.
16:44Others want robots that repel down crater walls or hop across the floor like pogo sticks.
16:49There are even ideas for drills that could melt frozen soil and trap water vapor like condensation on a cold
16:56soda can.
16:58The silver lining is that this water isn't going anywhere.
17:01Until we improve our technology, the supply will wait for us.
17:05That being said, space agencies are already making advancements.
17:10In fact, more than half a dozen new missions are lined up over the next few years.
17:16NASA's Artemis program is getting ready to send astronauts back around the Moon and then down to the South Pole.
17:24China's Chang'e 7 is planning to check out those dark craters.
17:29And private companies like Firefly and Blue Origin are gearing up to deliver equipment and experiments.
17:36Now, here's a bonus lesser-known fun fact.
17:39The Moon smells!
17:41When Apollo astronauts brought lunar dust into their landers, it mixed with the oxygen inside and ended up smelling pretty
17:48strong.
17:49They said it was like burnt gunpowder or fireworks.
17:53Lunar dust has nothing to do with gunpowder, but its particles are highly reactive.
17:58After sitting in space for billions of years, they reacted instantly with oxygen in the cabin, creating that smoky odor.
18:06Future explorers are definitely going to notice that smell, too, since lunar dust tends to stick to everything.
18:13Let's hope that, aside from everything else, scientists will work out air fresheners for the Moon base.
18:20There's something happening inside the Moon, something that nobody expected.
18:25Not a dramatic shift you'd see on the outside, but deep down, where things seem frozen in time, scientists have
18:32uncovered a hidden layer of what you could only call moon goo.
18:37Remember those school lessons about the crust, mantle, and core?
18:41Much like the Earth, the Moon is made up of layers – a crust, mantle, and core.
18:46However, the Moon's core is much smaller compared to ours.
18:50Earth's core is huge – it makes up about a third of our entire planet's mass.
18:55The Moon's core makes up only about one to two percent of its mass, and its diameter is about one
19:01-fifth the diameter of the Moon itself.
19:03It's surrounded by a hard, rocky mantle.
19:07But it turns out that between these two layers – that mysterious goo layer – and it's way more important
19:13than you might think.
19:14The layer is soft and partially molten, ebbing and flowing like the tides in our oceans.
19:20It rises and falls, stretching and shifting as if it were alive.
19:25Its movement isn't chaotic, but subtle and regular.
19:28We always knew that the Moon influences our seas and oceans, causing tides with its gravity.
19:35But it turns out that we influence it back.
19:38The goo ocean reacts to the gravitational dance between Earth and the Sun.
19:43Also, the molten layer could be made of ilmenite – a very intriguing material.
19:49Ilmenite is rich in titanium – a strong and lightweight metal that we really love over here on Earth.
19:54Titanium is used in everything from airplane parts and spacecraft to medical devices.
20:00Even in everyday items like bikes and laptops.
20:03All because it's incredibly strong and very resistant to corrosion and heat.
20:08So, if the Moon might have a molten layer rich in ilmenite, that would be awesome.
20:14Astronomers are already planning for lunar bases.
20:16And if we had a material to build structures, spacecraft, or even tools for astronauts right there, that would be
20:24a game-changer.
20:25Otherwise, we'd need to transport materials from Earth, which is extremely costly.
20:30This is our first tangible sign that the Moon is not just a cold, boring rock.
20:35Instead, it's dynamic, living, and breathing, with moving forces beneath the surface.
20:41NASA used new special tools to discover this – the Gravity Recovery and Interior Laboratory and the Lunar Reconnaissance Orbiter.
20:50These are both space missions designed to study the Moon.
20:53But they don't just look at the surface like a telescope.
20:56Instead, they help measure things we can't see with our eyes, like the Moon's gravity and how it changes over
21:03time.
21:04GRAIL sent two small spacecraft around the Moon named Ebb and Flow.
21:09Clever!
21:10The idea was for these spacecraft to fly close to each other and measure tiny differences in the Moon's gravity
21:17as they go.
21:18It's like they were feeling the Moon's invisible pull in different places.
21:21If the Moon's gravity was stronger in one spot, the spacecraft moved closer together.
21:27And if it was weaker, they moved farther apart.
21:30This helps scientists understand what's going on inside the Moon, even if they can't actually go there.
21:36And the spacecraft intentionally crashed into the Moon in December 2012 to end the mission.
21:42The Lunar Reconnaissance Orbiter is a bit different.
21:45It takes super-detailed pictures of the Moon and collects other important information about its surface.
21:50By combining the information from both GRAIL and LRO, we were able to find this goo layer.
21:57But this discovery actually challenges everything we thought we knew about lunar geology.
22:03How did this molten layer get there?
22:05How long has it existed?
22:07And, perhaps more fascinating, how it stayed warm for millions of years?
22:11That's a million-dollar question.
22:13The Moon's core generates heat, just like ours.
22:16But it's not as easy as saying, oh, the core's heat probably keeps it warm and molten.
22:22Well, first, the Moon's core is much smaller and less active than Earth's.
22:26Meaning, it produces significantly less heat.
22:29Plus, the Moon is much cooler than Earth in general.
22:32With temperature dropping to minus 200 degrees Fahrenheit on the surface,
22:36how could this inner layer still stay in this flowing state?
22:39That's still a mystery.
22:41In any case, this goo could actually explain a lot of stuff about the Moon.
22:46For example, astronomers were exploring moonquakes and how they happened.
22:50Now they think that it might be this semi-molten layer shifting and moving beneath the surface.
22:56Now, beyond the Moon itself, it also tells us more about other celestial bodies.
23:01If the Moon, something we considered basically a huge static rock, has such a dramatic life,
23:07what about other planets, moons, or asteroids?
23:10Could they also hide similar hidden movements beneath their surfaces?
23:15We can even understand our own planet better, learn more about how tides and similar stuff works.
23:21There are so many great discoveries we've been making on the Moon.
23:24Recently, we found some awesome stuff beneath the surface.
23:28Massive caves, hidden for millions of years.
23:31For over 50 years, scientists have suspected that the Moon's surface is full of underground tunnels and caves.
23:38These are known as lava tubes because they were formed by lava. Duh!
23:44Millions of years ago, the Moon was pretty unstable.
23:46It underwent some volcanic activity, causing eruptions.
23:50When a volcano erupts, lava can flow across the surface.
23:54As the outer layer of the lava cools and hardens, it forms a solid roof of dark material.
24:00It's actually what these famous dark spots on the Moon are.
24:03These are dark, hardened remains of ancient lava.
24:06But the hot, molten lava continues to flow through the center.
24:10Once the eruption ends and the lava drains away, what's left behind is an empty, hollow tunnel, hence a lava
24:18tube.
24:18On Earth, we have lava tubes in places like Hawaii or Iceland, where volcanic activity has created similar underground tunnels.
24:27The same thing happened on the Moon billions of years ago.
24:30Although they're much crazier compared to ours.
24:33In fact, lunar lava tubes are now thought to be some of the largest and longest in the entire solar
24:38system.
24:38One such cave was discovered beneath the famous Mare Tranquillitus, the place where Apollo 11 first landed.
24:46And it's at least 340 feet deep.
24:49Now, all these lava systems have remained hidden just beneath the surface, untouched for millions of years.
24:55Only now, they've finally managed to prove their existence.
24:59Scientists from the University of Trenta in Italy found them using special radar technology and advanced computer methods.
25:06These techniques let you see underground by sending radar waves.
25:10The waves bounce back and give clues about what's hidden underneath.
25:15By analyzing the way these waves reflected back, the researchers could detect the shape and size of the hidden caves.
25:22Now, the best thing about this discovery is that we could build all our bases there.
25:27These caves protect from radiation, harsh winds, and meteoroids.
25:32NASA even found evidence that some of these caves stay at a steady 63 degrees Fahrenheit.
25:38That's some crazy coziness for the Moon.
25:40And on top of that, there could even be some water there.
25:44So, humans could take shelter inside these natural tunnels and build entire colonies on the Moon.
25:50And I know what you're thinking.
25:52Could unexpected lunar monsters hide deep in those caves?
25:56Well, sure.
25:57There's a huge potential for exploring these caves and finding some awesome stuff.
26:02But even if we manage to find a miracle, like small life or microbial organisms,
26:08there's a 99% chance that there won't be actual animals or monsters.
26:12It would just be impossible for them to develop in such conditions.
26:16But it would make a great horror movie.
26:20Researchers want to send robots or drones to explore the tunnels first,
26:24and then see if they're safe enough for humans.
26:27And it's not just the US getting in on the action.
26:30China is also investigating the possibility of using these Moon caves as a future base,
26:35showing that the race to explore and settle the Moon is eating up.
26:42Okay, I officially give up on the hope that the Moon is made of cheese, after all.
26:47Wow, not even Gouda.
26:48The shiny lunar ball, or a curved banana, or half of a coin depending on what phase it's in,
26:55has different layers inside, just like Earth.
26:57One of these layers is called the inner core.
27:00About 20 years ago, scientists were observing how the Moon rotates.
27:04Using that data, they concluded that it had a fluid outer core.
27:08But the inner core was hard to study, so they didn't know if it was solid like a rock,
27:13or molten like a hot liquid.
27:15But things are clearer now.
27:18Astronomers have collected data from different missions, including the Apollo missions,
27:22where astronauts went to the Moon and gathered information themselves.
27:26Plus, they've used a special technique called seismic data.
27:30This method is all about studying how sound waves move through things.
27:34Take earthquakes on our planet as an example.
27:37When an earthquake happens, it creates waves that travel through the ground.
27:42Scientists can detect and analyze these waves to learn more about Earth's interior.
27:46The same idea can apply to other objects in our solar system.
27:49Or planets, or in this case, the Moon.
27:53When quakes, or moon quakes, happen, they generate sound waves.
27:57And by carefully listening to and studying these waves, scientists can create a detailed map of what's inside the object.
28:04They can figure out things like different layers, what they're made of, and how they're arranged.
28:10To check the Moon's deep interior, scientists also use something called laser ranging.
28:15This method measures the distance between the surface of the Earth and the Moon very precisely.
28:21And ta-da!
28:23Our natural satellite's inner core is a dense, solid ball made of iron, just like Earth's.
28:29It's about 310 miles wide, which is nearly 15% the size of the entire Moon.
28:34Researchers also have stumbled upon evidence that supports the theory that the layer between the Moon's surface and its core,
28:42called the mantle, has been moving around as the Moon evolved over time.
28:47This movement is something we call lunar mantle overturn.
28:51And it could explain why we find elements rich in iron on the lunar surface.
28:56Mantle material ends up being carried upward.
28:58And the volcanic rock remains in the Moon's crust.
29:03Some of the materials in this rock were too dense, like me.
29:07So they just sank back through the lighter crust material all the way to the core mantle boundary.
29:13It's like a cycle where the Moon's mantle material goes up during volcanic activity, carries iron-rich elements to the
29:20surface, and then sinks back down.
29:23There's another mystery scientists have been trying to solve.
29:26What caused the Moon's magnetic field to weaken and nearly disappear over time?
29:32It seems that now that we know about the iron core and the global mantle overturn, we might get some
29:38more answers about the Moon's magnetic field.
29:40Knowing what the inner core is like can help us better understand the Moon's history as well as the history
29:46of our entire solar system.
29:48Now, one of the theories that's widely accepted about the origin of the Moon says there was a massive collision
29:54between Earth, in its early stages, and another mysterious object in our solar system.
29:59It's called the Large Impact Theory, and this collision was so strong, it ripped off a big chunk of the
30:06primitive molten Earth.
30:08I mean, not so big compared to what's left. If you put a U.S. nickel next to a green
30:13pea, you get a good idea of how big our planet is compared to the Moon.
30:17Now, this chunk was set into orbit around our planet. And this might have happened about 95 million years after
30:24our solar system formed.
30:27The object that collided with Earth could have been about 10% the mass of our home planet and roughly
30:32the size of Mars.
30:34Well, it makes sense, Earth and the Moon do have similar compositions after all.
30:39Of course, there are other ideas about how the Moon formed. One says that the gravitational force of our planet
30:45captured it.
30:48This means that the Moon was just an object innocently passing by when suddenly it got attracted and pulled into
30:55Earth's orbit.
30:56There's even a hypothesis that Earth stole the Moon from Venus. Ooh.
31:00In that case, the Moon shouldn't complain. I guess the view is way better here.
31:05So yeah, the Moon and Earth are similar when it comes to rocks and some minerals.
31:09But the Moon doesn't have the same atmosphere as our planet.
31:13It's atmosphere is thin and consists of some weird gases that include potassium and sodium.
31:19Which is not something you can find in the atmosphere of Mars, Venus, or Earth.
31:23And the rocks on the Moon don't contain water.
31:26But that doesn't mean there's no water at all up there.
31:30A long time ago, in the 17th century, astronomers saw large dark spots on the Moon's surface.
31:36One of these astronomers thought these spots looked like oceans.
31:40And he called them maria, which means seas in Latin.
31:44Other astronomers also made maps of the Moon, and they used the term maria to describe these dark spots.
31:50For example, Mare Tranquillitatis translates to Sea of Tranquility, where Apollo 11 made its touchdown.
31:58But it seems those dark spots are not actually oceans.
32:01They are planes made of hardened lava that erupted long ago.
32:05These volcanic eruptions left behind smooth flat areas called basalt planes.
32:11In the late 1800s, one sky watcher studied the Moon and found it didn't have an atmosphere.
32:18Without an atmosphere, there are no clouds and no air to keep water from evaporating.
32:23So scientists thought that any water on the Moon would just disappear right away.
32:28They believed the Moon was totally dry.
32:31But then, in 1961, one physicist had a different idea.
32:36He pointed out there could be water on the Moon in special areas called permanently shadowed regions.
32:43These are spots on the Moon where the Sun doesn't shine, so they stay dark all the time.
32:49Water ice could exist in these dark areas because they're extremely cold and the ice wouldn't evaporate.
32:56But when astronauts from the Apollo missions went to the Moon, they brought back soil samples,
33:01and scientists found no signs of water in them.
33:04So everyone went back to thinking that the Moon was completely dry.
33:08In the 90s, NASA focused on these shadowed craters and found high concentrations of hydrogen,
33:15which meant there could be ice at the Moon's poles.
33:18They still weren't certain, so they kept digging and, after a while,
33:22found hydrogen trapped inside tiny beads of volcanic glass.
33:26Since there are no active volcanoes on the Moon today,
33:30which means water probably was present on the Moon when these volcanoes erupted long ago.
33:35Plus, there could be way more water back in the early days of our Moon.
33:40In 2020, NASA's SOFIA mission showed us what we'd been looking for for a really long time.
33:47There is water on the Moon, after all.
33:49It turns out the water is hidden within the grains of lunar dust
33:53or sticking to the surface in the sunlit areas of the Moon.
33:56So there are no oceans like we have on Earth, but at least there's something.
34:02The question remains, how did water even get there?
34:06It seems the Moon had a chaotic history back at the time when it was forming,
34:10as probably most of the planets and moons in our solar system.
34:13So there is some evidence that water came there from comets hitting its surface back in the old days,
34:20or maybe even keeps on coming from those that are slamming into the Moon right now.
34:26We're talking about a chaotic situation where icy micrometeorites collide with the Moon's surface,
34:32and dust then makes an even bigger mess when interacting with the solar wind.
34:36But we're waiting to find out more about this.
34:39Because, as we all know, when you mention water, you also inevitably talk about life.
34:46That's why we want to know more, for instance, about all that ice hidden in polar craters on the Moon.
34:52Maybe it can teach us more about how life developed on Earth.
34:56Maybe comets brought all the necessary elements here.
34:59Then, what if there are some of those elements stuck in the ice on the Moon, too?
35:04Hmm.
Comments