Transcription
WILLIAM SHATNER: Mars. A glowing red orb in the night sky. A desert planet that could hold signs of extraterrestrial life. A new frontier for the future of humanity. For centuries, Mars has been an enigma in the night sky, beckoning us to unravel its mysteries. Now, as a new era of space exploration begins, we have never been closer to setting foot on its desolate surface. But what will we discover when people are finally able to explore the Red Planet? And could we possibly find evidence that life exists there? Well, that is what we'll try and find out. ♪ ♪
SHATNER: Scientists and engineers working at NASA's Jet Propulsion Laboratory... -(cheering) -...celebrate, as some 245 million miles away from Earth, the Perseverance Mars rover lands on the surface of the Red Planet.
KIRSTEN SIEBACH: I am a participating scientist on the Perseverance mission. Landing on Mars is a really complex operation. We had been thinking about this mission for a decade before landing, building the rover, building the instruments, designing everything about it. It had been flying to Mars for just over seven and a half months. To watch Perseverance being lowered by a sky crane in the Mars atmosphere, I-I was speechless. That incredible engineering is so inspiring.
STEVEN BENNER: Perseverance is now on the surface of Mars, looking around for habitability, the potential for life, minerals. And so Perseverance is going to be a tremendously valuable scientific enterprise.
SHATNER: Many scientists believe that the data being collected by Perseverance will be a giant leap forward in our understanding of Mars. But this mission is just the latest chapter in humanity's long quest to unravel the secrets of the Red Planet. In fact, our fixation with Mars dates back thousands of years.
ROBERT SCHOCH: Mars has been an obsession since ancient times. And one could ask, why is Mars such an obsession? I would suggest that it's sort of a mysterious planet. It's a red planet. Red is a very important color for ancient and indigenous cultures. It's the color of blood. It's a sacred color. It's the color of life. It's the color of fearsomeness, the color of the warrior. It was just all really tantalizing for ancient people.
IWAN RHYS-MORUS: The Babylonians named the planet after Nergal, their god of war. Similarly, the Greeks named the planet after their god of War Aries; it was the star of Aries. And of course, the Romans called the planet after their god Mars. And Mars's astrological significance is quite interesting and revealing. The astrological symbol for Mars is a circle with an arrow coming out of it. That's the modern symbol for maleness, for masculinity, virility, warfare, solidity. So, as far back as our history goes, it's clear that Mars always had particular connotations built into human understandings of the planet's significance right from the beginning.
AMY SHIRA TEITEL: We have been fascinated with Mars for a long time because there's no planet we can see as well as we can see Mars. Venus is obscured by clouds, and everything else is too far away, but Mars is there. Before we had telescopes to be able to reveal anything on the surface, it was the red dot in the sky. And it, actually, if you observe it from Earth, seems to move backwards in its orbit every once in a while. It confounded scientists, and people were moved to study it.
SHATNER: Although humanity's fascination with Mars began in antiquity, the development of telescopes ushered in a new era of investigation of the Red Planet.
ROD PYLE: In the 1600s, here comes Galileo Galilei, a brilliant inventor, scientist, artist. He builds an early telescope and starts looking at the planets. And he's wondering, why are these stars different? And this is really when it began to become clear that these were places. They weren't deities, they weren't stars. They were places. They were other rocky worlds like Earth. And this was a revelation. Once human beings realized that Mars was another planet, we were really curious now, because we wanted to know, do we have neighbors out there in space? We long had a suspicion that it's gonna look like Earth, it's gonna feel like Earth, and we hoped that it would be the kind of planet we might be able to go to someday, and there might actually be living things there.
RHYS-MORUS: During the second half of the 19th century, fascination with Mars and the possibilities of life on Mars really takes off. The American astronomer Percival Lowell enthusiastically takes up this search for evidence of civilization on Mars. So he establishes his own observatory, the Lowell Observatory in Flagstaff, Arizona, carries out detailed examination of the Martian surface, and then publishes a number of books in 1895 describing what he's seen. And this really strikes a chord. And then, of course, famously, just a few years later in 1898, H.G. Wells writes The War of the Worlds. Wells chooses Mars as the home of the alien civilization that's going to be invading Earth precisely because Mars was already in the public eye.
NICK POPE: Mars has become synonymous with the idea of aliens and sometimes alien invasion. We get movies like Mars Attacks! and others. So, there is this idea that if there are other life-forms out there, particularly in our own solar system, Mars is where they might come from.
SHATNER: The idea of Martians invading our planet makes for entertaining science fiction. But scientists believe they are closer than ever to finding evidence that some form of life did, in fact, once exist on the Red Planet. But why do experts think that a barren planet like Mars could have, at one time, given birth to life? Imagine for the moment, being a Martian explorer three to four billion years ago. What would we see? Instead of seeing this dead planet with craters and-and gigantic mountain ridges, we see riverbeds, oceans. We see a blue planet that looks ripe for the creation of life.
BENNER: Today, Mars still has a large amount of water ice just below the surface. And on Earth, wherever we find that kind of ice, there is life in it. So, it's quite likely that if Mars, uh, generated life four billion years ago, it is still there today, and we almost certainly know where to go looking for it. And in fact, the Perseverance rover that's on the surface now is looking at places on Mars where life might have been in the past.
SHATNER: In their search for evidence of life on Mars, NASA scientists have sent the Perseverance rover to investigate a particular area of the Red Planet that is known as the Jezero crater.
SIEBACH: Jezero crater was formed by a large impact sometime around 3.8 or 3.9 billion years ago. Now, we know that at some point, that this was a lake about the size of Lake Tahoe in the Western United States. And so Jezero crater is great, because we know the right ingredients are there to preserve ancient life. We know that there was ancient water, and we know that Jezero crater was ancient enough that it was active in the time when life might have formed on Mars. And so, because of that, I am more optimistic that with Perseverance, we might be able to find some of these organic materials and some of the possible evidence for ancient life.
SHATNER: Could NASA's Perseverance rover actually find evidence of microscopic Martian life in the Jezero crater? We'll soon find out. But what will happen if we do discover signs of life on Mars?
SIEBACH: It's a very exciting mission, because if we find evidence for life on Mars, it means that when the conditions are right, life can start, and that means it's all over the universe. That changes our understanding of what we are, are we alone, where do we come from? So, that kind of revolutionary possibility of understanding is worth a lot of exploration.
RHYS-MORUS: If the current missions succeed, and if there is life on Mars, then, well, it will be a different world for all of us. The implications of finding evidence of life on Mars are, frankly, staggering. But if it's true that Mars was once a blue planet, teeming with microbial life, then how did it turn into the lifeless red desert it is today? There are those who believe a clue may be found in an ancient cataclysm that was so devastating it left a giant scar across the surface of the planet.
SNATNER: The United Arab Emirates becomes the first Arab nation to send a space vehicle to the Red Planet. The state-of-the-art satellite, named Hope, will spend two years collecting information on how sunlight, dust and temperature have affected the Martian atmosphere in the past and present. Astronomers hope this mission will bring answers to one of the most enduring mysteries of Mars: how did it become the Red Planet? When you look at Mars tonight, in the night sky, for example, you see this red dot. Why red? Ferric oxide. It's the Rusty Planet. It's iron rust. But it wasn't always that way. Billions of years ago, it was very similar to what the Earth looks like today. The data coming from the Hope weather satellite could be essential for us to piece together this jigsaw puzzle. We had a lush planet, a blue planet, teeming with the possibilities of life. And then we have this dead, barren planet of today. What happened in between?
SHATNER: Scientists have theorized that Mars was changed by some kind of massive cataclysm in the distant past, causing it to become barren and lifeless. But it's well-known that Earth has endured numerous global catastrophes, and our planet is still teeming with life. So, what was different about Mars?
KAKU: Natural disasters happened rather regularly on the planet Earth. We have volcanic activity, gigantic earthquakes, meteor impacts blanketing out the Sun, collapsing agriculture, causing chaos. So, in other words, planet-killing events. But we are here, the Earth is teeming with life, and Mars turned out to be a dead planet. We don't know for sure, but we think the culprit is Mars has a very low atmospheric density, only one percent the atmospheric density found on the planet Earth.
SIEBACH: Mars once had that dense atmosphere, but somewhere around three billion years ago, that atmosphere was stripped away. And as the atmosphere thinned, liquid water became less and less stable and would have evaporated. So, if there was life on Mars, it lost one of the key ingredients for habitability.
SCHOCH: We think the atmosphere on Mars was initially eroded by impact. That is, meteorites, asteroids, physical impactors on the Martian surface stripped away the atmosphere of Mars.
TAYLOR: When you look at Mars you realize that the northern hemisphere looks more like plains, and it's very flat. But the southern hemisphere of Mars is heavily cratered, and that suggests that there are a lot of impacts there that could actually have destroyed the atmosphere and everything else on Mars.
KAKU: Without the atmosphere to preserve the integrity of the planet, as the solar wind from the Sun hits Mars, water would boil by itself, would vaporize by itself, and be lost into outer space. And as a consequence, liquid water cannot remain liquid on the surface of Mars.
SHATNER: Did ancient asteroid impacts destroy the atmosphere of Mars? Perhaps. But some scientists suggest there was an even more powerful disaster that was responsible. And as evidence, they point to a curious feature of the planet's surface known as the Valles Marineris, or as many like to call it, the scar on Mars.
TAYLOR: The Valles Marineris looks as if something just gouged out of the surface of Mars. And the question is, did it occur naturally? Because we don't really understand what happened.
SCHOCH: One theory that I've been exploring recently is that the Sun has major solar outbursts that spread out throughout the solar system traveling at very high speeds. Plasma: electrically charged particles, protons, electrons, other charged ions. And when these hit planets, you can imagine them as huge lightning bolts, hitting the surface of the planet. And this can gouge out what look like canyons. And this may have been a major contributing factor to the loss of the atmosphere.
KAKU: We have lots of theories as to the geologic and atmospheric profile of Mars, but to be certain, we have to go there and actually touch and feel and analyze these things. From a distance, from millions of miles away, we can only speculate about what could be causing these unexplained surface features on Mars. Will we ever know what caused Mars to become so dry and desolate? Well, there are those who believe that one way to learn more about the past is by examining possible evidence that the Red Planet was once home to an ancient civilization.
SHATNER: The Cydonia Institute, a group of researchers that investigate strange formations on the surface of Mars publishes a study analyzing satellite photographs taken of the planet. The images show what the researchers claim look like four and five-sided pyramids and a series of curious mounds.
HAAS: This whole idea for The Cydonia Institute started when NASA announced in 1991 that they were gonna return to Mars with the Mars Observer. And over the last 30-some years of our group studying NASA photographs, we have found an enormous amount of evidence that led us to believe there are artificial structures on Mars. What we're trying to do is get a preponderance of evidence together so that we can prove the point that there's ruins all over the planet. And just as you would here on Earth, you're gonna look for straight lines, parallel lines, circles, squares, rectangles, things of this nature. And when you find them, then you can start to zoom in on areas and look for even, uh, stronger details.
HAAS: When the Perseverance landed, one of the first things that I noticed was a conical pyramid in the distance. The camera there took a beautiful couple pictures of it. It doesn't make any sense to me geologically how that could happen. That was one of the biggest anomalies that was seen. We're still gonna get better and better pictures, we're going to have more to look at, as NASA releases all of these images from Perseverance. But we haven't gotten there yet, because the Perseverance, they landed in the middle of a big lake. And I think the only thing we're gonna find there is probably shells, things from an aquatic environment. I think all of the ruins that people are looking for, they're gonna be found once they drive a little further, in the perimeter.
SHATNER: Cities and ruins on the surface of Mars? Could the remnants of an ancient Martian civilization have really been hiding in plain sight? It's a question that researchers have pondered for more than four decades, ever since NASA sent the first satellites into orbit around the Red Planet. Mars has piqued the curiosity of scientists and the public for millennia, but it really wasn't until the dawn of the Space Age that we started getting an idea of what the planet was really all about. Mariner 4 in 1965 flies past the planet, sends back 22 fuzzy photographs, and Mars looks just like the Moon. And then we sent two spacecraft, Viking 1 and Viking 2, in 1976. So we got tens of thousands of photographs from orbit. Since then, as we get better-resolution photographs from the surface of Mars, people have thought they saw all kinds of things there. There is a not insignificant group of people that think that we've already discovered life on Mars, that there are structures there, that there are buildings, obelisks, some kind of indicator of ancient cultures that is being covered up.
POPE: You look at images of this, and people are spotting all sorts of strange shapes and pyramids, structures of some kind, on the Martian surface. Is it something left by a lost civilization as maybe a-a monument to themselves and their achievement?
SHATNER: For some, the most compelling evidence that an ancient civilization once existed on Mars can be found in a photograph which shows what appears to be a large structure, that has come to be known as the Face on Mars. In Viking lander photographs, it was discovered that there was this weird-looking structure that looks, for all the world, in the Viking photos, like a face.
MILLER: Everything is proportional. The-the face is a mile and a half, two miles long. The eyes are a quarter mile. The nose about a half a mile. So it's not a small structure, it's a very large structure. I believe that the Face on Mars was created from, uh, possibly an existing mesa.
SCHOCH: It's not just the face, but on top of that, people saw what they called the D&M Pyramid, which is this weird five-sided structure that looks like a five-sided pyramid. People were claiming this had to be artificial structures.
HAAS: The D&M Pyramid is a five-sided structure. The five faces have all this very symmetrical geometry of 30 degrees, 60 degrees and 90 degrees. It's just a remarkable out-of-place artifact on the surface of Mars. What researchers looking at this found is that because of its exquisite geometry, there's no way that this could be created naturally.
SHATNER: Decades after the famous photograph was taken, the Face on Mars continues to inspire both fascination and debate. Many researchers believe it and other curious formations on the Red Planet merit further study and discussion.
POPE: Some of this may just be a trick of the light, funny-shaped rocks, that sort of thing. But only one of these things has got to be the real deal, and we're in game-changing territory. Was there once an advanced civilization on Mars? Some of the features on the planet's surface definitely make you wonder. But there are those who claim that we don't need to send probes millions of miles away to search for signs of Martian life. They believe that Martian life-forms have already traveled here to Earth.
SHATNER: President Bill Clinton announces that NASA scientists have made a remarkable discovery. Good afternoon.
SHATNER: The scientists examined an ancient Martian rock that fell to Earth as a meteorite in the distant past and found evidence which suggests that the meteorite once contained microscopic Martian life inside it. More than four billion years ago, this piece of rock was formed as a part of the original crust of Mars. After billions of years, it broke from the surface and began a 16-million-year journey through space that would end here on Earth. It speaks of the possibility of life. If this discovery is confirmed, it will surely be one of the most stunning insights into our universe that science has ever uncovered. Its implications are as far-reaching and awe-inspiring as can be imagined.
TEITEL: This asteroid, called the Allan Hills asteroid, was found in Antarctica. It proved really valuable because we've never been able to bring samples back, but now we have this piece of Mars to study in a lab on Earth, which is really important, because as our instruments get better, we can continue to study it and learn more.
PYLE: So when they crack the meteorite open, they looked inside, and they saw what looked like fossilized life-forms. They look like little tiny worms and other bits of potentially fossilized biological matter. And these were really small. They were smaller than even a single-celled creature would be on Earth. But they looked like life-forms. And there are other indicators, in terms of the composition and the makeup and the distribution of them, that led them to think that they might be life-forms. It was so remarkable-looking, that it merited an announcement to the public, and it caused a major stir.
RICHARD ZARE: Allan Hills meteorite really changed the field of astrobiology. There was a bunch of lines of evidence that appeared to us to suggest the possibility that this had something to do with primitive life.
SHATNER: According to experts, it's possible that the Allan Hills meteorite actually brought microscopic evidence of Martian life to our planet when it landed here. And the idea that any form of life can travel from Mars to Earth has caused many scientists to consider an even more profound possibility: what if life on Earth was seeded from Mars?
KAKU: There's an idea in the field of astrobiology called panspermia, and the essence of the idea is this: four billion years ago, there may have been life on Mars-- microbial-- but something. A rock slams into Mars, you know, some asteroid, it kicks up a big clod of Martian dirt. Some of it gets kicked up fast enough to just leave Mars altogether, wanders around the solar system, but some of it, by chance, would fall on the Earth and might infect the Earth.
KAKU: The panspermia theory cannot be dismissed. And one reason is as follows. In the early Earth, we were hit by meteors and asteroids. In fact, it turns out that almost 300 meteorites from Mars have been identified. This means that perhaps DNA may ride on these meteorites as it goes from planet to planet. So if, for example, life were to start on Mars first, and a rock carrying Martian DNA were to land on the planet Earth, then boom, life gets off the ground. So, one theory is that if you want to see a Martian, look in the mirror tonight.
PYLE: Has life migrated possibly from Mars to Earth? It's possible. We can't say yes, we can't say no, yet. Any Mars scientist you talk to, any planetary geologist will tell you, they would love to have that dinosaur bone moment, they would love for the rover to roll up and find a giant fossilized femur, or even something alive. We may find these things someday. But we're not gonna know until we get there and find life on Mars, and are able to look at it, get some DNA out of it and figure out if it ended up on Earth, or if it's something completely alien to us.
SHATNER: If scientists are someday able to confirm that life came from Mars to Earth, then it begs the question, what would such a discovery mean to humanity? Mars might hold the key to understanding the origin of life. It has a lot of potential to help us understand where we fit in the biggest-scale picture of the universe and the history of the Earth, because we want to understand the history of this planet. How did we get to a place where humans were here? Science is based on things that are testable, falsifiable, reproduceable, and as Carl Sagan once said, "Remarkable claims require remarkable proof." But if, if we have one solid piece of evidence that Mars seeded the Earth, that would force historians of science to rewrite all the science textbooks and change our role in the universe. Did life originate on Mars and then evolve on Earth? If scientists really believe that it could be possible, then perhaps one day, we'll find the proof here. Or maybe it will be revealed when astronauts set foot on the Red Planet itself.
SHATNER: NASA announces a series of bold new technologies they are actively developing to help astronauts eventually reach Mars, including cutting-edge propulsion systems, next-generation space suits and nuclear fission generators. This is such an exciting time to be working on Mars. There is unprecedented interest. There are more government space agencies and scientists around the world working towards space exploration than there have ever been before. We have new rockets, different instruments, and we're at a time when technology is getting closer to sending people to Mars. It's-it's really fun. It's really exciting.
SHATNER: In addition to NASA, numerous space agencies from around the world have also stepped up their efforts to send people to Mars. There are many who believe that this increase in activity echoes the Space Race from the 1960s, when humanity strived to land men on the Moon for the first time.
PYLE: July 20th, 1969, Apollo 11 lands on the Moon, and this is one of the proudest moments in human history.
NEIL ARMSTRONG: That's one small step for man, one giant leap for mankind.
PYLE: Two men down on the surface, 600 million people watching around the world, more listening to their radios, people can barely believe it. They stayed on the Moon's surface for a day, they achieved all their goals, and it was just a watershed moment in Western civilization. -(people cheering) -And the next big question is what are we gonna do after the Apollo landings? Wernher von Braun, the famed rocket scientist of German origins, published a book called The Mars Project, where he actually laid out the first real technically accurate engineering plan on how we could do this. And they wanted to do it by the mid-1980s. But by the time Richard Nixon came into the office, we realized it was gonna be a much bigger job to send humans to Mars than we thought. But we continued to think about it, and it continues today. We want to go beyond to Mars and find out what's happening on that world, because a human being can do in about 15 minutes what it takes a robot six months to do. So you have to send people.
SHATNER: It's not just NASA and other space agencies that have their sights set on Mars. Ordinary people are also quite eager to travel to the Red Planet. In fact, when it was announced in March of 2020 that NASA would begin recruiting a new generation of astronauts for its first-ever manned mission to Mars, 200,000 people submitted applications.
ZARE: I think it's the nature of human beings to try to expand further. There's a sense of exploration, of-of being an explorer, of being the first to go somewhere, and that really motivates a lot of people. This is a great time in space exploration.
SIEBACH: We're at a time when we have pictures of Mars in our living rooms. We have pictures of Mars on our computer screens. We're seeing that-that, yes, we can reach out to Mars. We can see it, we can touch it. We're so close. And that's really exciting to see.
SHATNER: One member of the new generation of explorers that is hoping to be selected to go to Mars is 20-year-old Alyssa Carson. She is so driven to be among the first humans to set foot on the Red Planet that she's been preparing for such a mission her entire life.
ALYSSA CARSON: Mars has kind of always been my ultimate goal, uh, mainly just because of the curiosity of it, you know, what is on Mars, no one's been there before, why not go? So I started out by going to all the NASA space camps, I then joined a citizen science research organization. And with them, I've been able to do g-force trainings, microgravity flights. Parabola two: success. Water survival training, space suit evaluations. But, you know, I definitely would say that the thing that I'm most proud of is the experience of being on the NASA MER 10 panel with PhDs, scientists, just so many amazing people. I almost really can't explain why I have such a passion and drive for it. If the only option was a one-way trip, then I would still want to go.
SHOSTAK: When are we gonna go to Mars? I get that question a lot. You know, people who are in the rocket business say, "Well, certainly within ten years, we could send somebody to the Red Planet." And you might say, but why do that, right? It's dangerous, uh, getting them there, bringing them back. There are all sorts of technical problems, not the least of which is the fact that the Sun occasionally burps high-speed particles into space, and those particles would zip right through the skin of any rocket and give everybody inside instant cancer, that kind of thing. I mean, these are, these are serious problems.
SHATNER: Why are so many people willing to put their life on the line for a perilous journey to Mars? Well, there are those who believe that we are motivated to go to Mars because there is a profound connection between humans and the Red Planet. And that evidence of this connection can be found in the human body.
TAYLOR: The human body produces a good fat and bad fat, and the good fat, it turns out, we produce more of if we're held at an average temperature of 67 degrees or a little bit lower than that on a regular basis. I find that an interesting correlation that the temperature in the summertime on Mars is 67 degrees Fahrenheit. Does that suggest that humanity is more suited to be healthy on Mars than they are on Earth? I don't know. There are other aspects of Mars that is interesting with the human physiology. When astronauts spend a long period of time in microgravity, their internal biorhythm clock resets, not to a day that's as long as a day on Earth, but in fact it resets precisely to the time a day is on Mars, which is a little bit different by a few minutes. Why does this happen? Is it telling us that there's something in our DNA, in our genetic code that is more suitable for Mars than it is for Earth? We don't know, but that is a possibility. Could it really be possible that Mars is in our DNA? And that by going there, we would actually be returning home? There are many who believe it's true, and feel so strongly that humanity's future lies on Mars that they're investing everything they've got to get us back there.
SHATNER: On the 60th anniversary of the United States' first-ever manned spaceflight, aerospace company SpaceX, founded by billionaire Elon Musk, successfully completes the ninth test flight of its prototype launch vehicle. Code-named Starship, the reusable transport is the latest advance in a new space race funded by private entrepreneurs competing to see who will be the first to send humans to Mars.
KAKU: Elon Musk envisions sending perhaps a million colonists to the Red Planet. Is that possible? Well, from an engineering point of view, yes, we have the technology. It's just a question of assembling the resources. But then the bigger question is, who's gonna pay for it? And that's why we're entering the second golden age of space exploration. Things are changing. Silicon Valley billionaires are funding their own fleet of rockets, paid for not by taxpayer's dime, paid for by their own funds. Elon Musk is in competition with Jeff Bezos, the richest man on the planet, who has funded his own private spaceport in Texas with a fleet of rockets.
SHATNER: Recently, SpaceX announced plans to begin the colonization of Mars by the year 2026, with the goal of establishing a permanent, self-sustaining city on the Red Planet by the end of the 21st century. But what would motivate a billionaire like Elon Musk to gamble his massive wealth on such a risky endeavor?
TAYLOR: Elon Musk is gonna go to Mars. He's motivated to do so, and the question is, d-does he see, like, the next big amount of money there? There's likely oil on Mars, methane on Mars, there's very likely minerals, rare earth elements that are very expensive, and could create a huge economic engine. But I'm not so sure that that's his pure motivation. He also seems to be motivated by the survivability of humanity by spreading out to the planets and the stars.
KAKU: Elon Musk had a dream as a child. He read the Foundation science fiction series by Isaac Asimov, which talked about a galactic civilization. So, he thought to himself, "Why not this "be the destiny for humanity, to become a multi-planet species?"
SHATNER: Will our journey to Mars be a mission of survival or exploration? Only time will tell. But one thing is certain. Despite the inherent danger involved with traveling to Mars, human beings are compelled to learn more about and get closer to the Red Planet. We've been exploring Mars basically since the beginning of the Space Age, and we've had a near-constant presence on Mars, on the surface, since the late 1990s, but we still don't know too much about the planet. We've only gone with these rovers and landers that look for very specific things, whether it's looking at geology or looking at chemistry or looking at the atmosphere.
KAKU: Believe it or not, we have only scratched the surface of Mars. We've never been to the ice caps. We don't know their state, we don't know their consistency. It's a big mystery, the polar ice caps. And also, Mars has some of the biggest mountains and the biggest volcanos in the solar system. We have never visited them. And so for all these reasons, Mars is still a hidden universe.
SIEBACH: Exploring Mars is so exciting because there are so many mysteries left to solve. Each rover mission, each satellite observation gives us one more little puzzle piece. All of these developments are-are absolutely thrilling.
PYLE: Human beings, as a species, seem to want to go beyond the next horizon. They want to crest that next mountain, they want to go over that next ocean. We're building these remarkable rockets, these incredible spacecraft to go to Mars. Once we get there, this is going to be a moment that's pivotal in human history. So, what do you think? Could there have been life on Mars in the past? And will our destiny lead us to travel there in the future? Well, while we may be surprisingly close to uncovering the Red Planet's secrets, until we can explore the surface firsthand, the mysteries of Mars will remain unexplained.
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