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00:00The following program is rated PG and may contain mature subject matter.
00:06Viewer discretion is advised.
00:08Since the invention of the wheel, humans have pushed the boundaries and possibilities to go faster, higher, and deeper than ever before.
00:35The engineering evolution of cars, ships, planes, trains, submersibles, and rockets has been a monumental journey of inspiration, innovation, sometimes failure, and success.
00:48So how did we get to where we are now, and where are we going next?
01:14We are living in an age where space travel is no longer limited to brave astronauts and national programs.
01:20Some of the world's most powerful rockets come from private companies, and every day, civilians have the opportunity to take a ride, for the right price, of course.
01:30We couldn't get 10 feet off the ground 100 years ago, and now we've got spaceships that are 10 billion kilometers away.
01:38From the first Apollo missions in the late 1960s to the 2020s, only 12 people in human history have ever stepped on any moon or planet beyond Earth.
01:48However, that very exclusive list could be about to expand.
01:53We're in the era of space tourism, where civilians, untrained people get to actually witness the view from space. It's really incredible.
02:02Driven by better propellants, more engines, and greater technology, space programs have trips to Mars within their sights.
02:09Maybe in the future, I'm getting on a two-day space flight to go see my family on Mars. That sounds quite attractive, doesn't it?
02:18The dangers of achieving liftoff are not to be taken lightly.
02:22Every step along the way, there's still things that can go devastatingly wrong.
02:26But the rewards are out of this world.
02:29The results of such lofty projects have the ability to change everything from improving Earth-bound travel,
02:35unlocking new resources that could power the cities of tomorrow, to building a future for humankind among the stars.
02:47One of the most exciting spacecraft of today is the Boeing CST-100 Starliner.
02:53Go Starliner.
02:55All systems are go for liftoff.
02:57The Starliner is capsule-like and designed to go to the International Space Station and return back to solid ground.
03:03Once the Starliner and its crew manifest have finished with their mission,
03:07it will undock itself autonomously and then descend down back to the planet, all pre-programmed.
03:15It will be equipped with solar panels such that it could essentially self-power its descent back down to the ground.
03:23We want to be able to reduce our footprint, and so the Starliner will be able to be reused up to 10 times.
03:30It's a real design challenge to be able to have the Starliner capsule survive for up to 10 different missions.
03:36One of the biggest challenges is re-entry.
03:38When the capsule is re-entering, there's a tremendous amount of heat that is a result of the friction between the air and the outside of the capsule.
03:47To be able to do this 10 times means they need a really robust design.
03:51They need to be able to handle huge heating and cooling cycles, and it's pretty incredible that they've designed to do that.
03:57In 2022, Boeing and NASA completed their crucial uncrewed mission to the International Space Station.
04:04The final test flight in preparation for the astronauts' first crewed flight, an Atlas V rocket blasted the Starliner into orbit.
04:12Using a series of sensors, the capsule autonomously guides itself into an open docking port at the space station.
04:19While in flight, the Starliner harnesses solar energy to generate power.
04:24Boasting more than 3,500 solar cells, this spacecraft creates approximately 2,900 megawatts of electricity.
04:34Starliner will bring the first crew rotation mission to the International Space Station as early as summer 2024.
04:41The first ISS component was launched in 1998, with the long-term residents arriving in the year 2000.
04:49Since then, over 250 astronauts, cosmonauts, and space tourists have visited from over 20 different nations.
04:57Maintaining and checking equipment, conducting science experiments, and installing solar panels are just a few of the critical tasks performed by the long-term ISS residents.
05:08While life at the ISS may seem pretty isolating, residents are known for playing pranks on their fellow astronauts.
05:15Astronaut Scott Kelly played one of the most outlandish pranks in space in February 2016,
05:21donning a gorilla suit and chasing astronaut Tim Peake around the ISS.
05:25Other astronauts have shockingly emerged from cargo bags and even snuck in a corned beef sandwich.
05:32Before the concept of visiting space was even a remote possibility, the physics behind the world's earliest rockets needed to take off.
05:40When we think about rockets and going to space, we're really talking about a controlled explosion.
05:46The amount of energy that's required to move mass into space is almost beyond human imagination.
05:54The shape of rockets is usually pretty consistent. They're long and they are pointy, and this helps cut through the air in our atmosphere.
06:01When a rocket is going up, it's being pulled by the gravity of the Earth, and the more the weight, the more the pull.
06:10Secondly, air is dense closer to Earth, and it gets lighter and lighter and lighter as it goes up.
06:16So the resistance this rocket faces is significantly less as it goes up.
06:23The force of gravity reduces, and the drag forces also reduces, because you are going through thinner atmospheres.
06:30The first use of rockets dates back to the 11th century, when the Chinese and Mongols were at war.
06:36During the siege of Kaifeng, the Chinese staved off the Mongolian invaders using a swarm of fire arrows, a simple form of solid propellant rocket.
06:46When we look back in antiquity at rockets, we think of the early Chinese rockets.
06:51These were chemical rockets. Basically, if you take sulfur, charcoal, and saltpeter and mix those materials together and ignite them, you have gunpowder.
07:00If you take that gunpowder and put it inside a tube, like a shaft of bamboo, all of a sudden you have a rocket.
07:06The use of similar rockets spread all the way to Europe and the Middle East, where they were used for both military and ceremonial purposes as fireworks.
07:15Today, NASA's spectacular Space Launch System holds the record for most powerful rocket to ever be successfully launched.
07:23NASA has developed the SLS rockets, or Space Launch System rockets.
07:27And these are being used on the Artemis mission, which is going to be used for travel to the Moon, and soon after, Mars.
07:33NASA's SLS rocket can produce 8.8 million pounds of thrust, which is 15% greater than the previous record holder, the Saturn V rocket.
07:42NASA's vision is to go back to the Moon and to Mars.
07:45To get there, we need spacecraft that are relatively large.
07:49We need to support a number of humans to go to the Moon for weeks or months at a time, and to go to Mars years at a time.
07:57So this means we're moving much larger masses to space to do this.
08:01To that end, we need a huge rocket.
08:04The SLS is powered by liquid hydrogen and liquid oxygen.
08:08Hydrogen is an extremely powerful fuel.
08:11It's very low density, and that's what we're looking for.
08:14We want for our rockets to have the maximum amount of energy for any given mass.
08:20So if your fuel's heavy, but it gives a lot of thrust, that's okay.
08:26But if you have a really powerful fuel that's really light, it's even better,
08:31because you don't have to accelerate all of that mass upward while you're moving.
08:36Engineers are looking for greener ways forward,
08:39and hydrogen is showing real potential as the rocket fuel of the future.
08:43Hydrogen can be obtained sustainably by using solar power to break down water.
08:48One of the great things about using a liquid hydrogen fuel source rather than a kerosene fuel source
08:53is the benefit it has to the environment.
08:55You're not burning off like a traditional fuel that leads to typical hydrocarbons.
08:58When you do your control burn with a liquid hydrogen, the byproducts are actually mostly water vapor.
09:05Liquid hydrogen has its benefits,
09:07but dealing with one of the lightest elements in the universe comes with its own set of hurdles.
09:13Hydrogen's a promising fuel, but it's very difficult to work with.
09:17It's the smallest element that we know of.
09:20And when you think of all atoms in space, whether they're iron or hydrogen,
09:25they're just these little tiny balls.
09:27And if hydrogen is much smaller than the steel tank that is holding the hydrogen,
09:32the hydrogen can actually make its way through in between the iron molecules and escape the tank.
09:37So hydrogen leakage out of the containers that we've built for hydrogen storage is a big issue.
09:43One of the challenges of carrying liquid hydrogen is that it needs to be stored at negative 253 degrees Celsius.
09:49Anything above that and it starts to evaporate.
09:51So this requires a pretty complicated cooling system that needs to be stored on the rocket.
09:55And if it starts to evaporate, you could be in space literally just losing fuel,
10:00leaving you with not enough fuel to return.
10:02And the other problem is if hydrogen does leak, it's explosive.
10:06Early examples of this were during the 1930s,
10:09when airships powered by hydrogen seemed to be the future of flight,
10:13until disaster struck in one of the most infamous catastrophes.
10:17You take the Hindenburg example, you've got a large volume of concentrated hydrogen.
10:22That hydrogen is leaking out into the air and all you need is a small ignition and it goes off.
10:28Centuries before NASA was reaching for the stars,
10:31the pioneers of rocketry were struggling to solve one of space exploration's biggest problems,
10:37how to break through the forces of Earth's gravitational field.
10:40Born in 1857, Russian rocket scientist Konstantin Tsiolkovsky devised a device and equation
10:48that became a fundamental principle of rocket science.
10:51He had been captivated by reading books such as From the Earth to the Moon
10:55and Journey to the Center of the Earth by early science fiction writer Jules Verne.
11:00Konstantin Tsiolkovsky was originally inspired by the works of Jules Verne.
11:04So we think about science fiction actually leading to kind of this wondrous inspiration
11:09that has taken us to the depths of space exploration that we're at today.
11:13He had two major contributions to the field of rocket science,
11:16the first of which being the calculation of trajectories.
11:20So he developed the math necessary for launching a rocket and determining where it was going to end up.
11:25This was crucial to space travel.
11:26And the second development was the concept of multi-stage rockets
11:30and that's where the rockets are essentially shedding their own mass the further up they go.
11:34So it ends up taking less weight and less energy the higher up you go.
11:38Tsiolkovsky's equation kind of deals with this idea of the moment of launch
11:43is kind of the most critical piece in terms of getting a rocket to space
11:46because at that particular point it's at its heaviest, it has the most mass
11:51and you need to figure out a way to counteract that to get enough thrust to get out.
11:56To perform a successful launch, rockets must produce a greater amount of thrust than their weight.
12:02The heavier the rocket, the more thrust is needed to blast off.
12:06Weighing in at 330 tons,
12:09NASA's Stage 2 Atlas V541 rocket produces 3.8 million newtons of thrust at full throttle.
12:17As one of the world's biggest rockets,
12:19this colossus launched the Mars Perseverance rover into action at Cape Canaveral in July 2020,
12:26kick-starting interplanetary flights.
12:29Perseverance has been roaming the Red Planet since 2021,
12:33searching for signs of past life and helping NASA to prepare for future human exploration.
12:39This epic launch would never have been possible without American rocketry pioneer Robert H. Goddard.
12:45Through his cutting-edge experiments, Goddard developed many of the basic principles of rocket science,
12:51including the use of fins for stability,
12:53the need for a pump to force fuel into the combustion chamber,
12:57and the concept of a rocket nozzle.
13:00We can use rocket fins to physically steer the rocket as it pushes itself off the air,
13:06but that only works up until a certain point.
13:08Eventually, once we surpass our atmosphere, there's not much air to push off of,
13:12and they become pretty useless.
13:14But they're very good inside our atmosphere to control the rocket.
13:17As a rocket ascends, the thrust direction may shift, causing the rocket to veer off course.
13:23To ensure the rocket stays on its flight path,
13:25we need something to help steer when there is no atmosphere.
13:29Once in space, the way that engineers and scientists have found to control rockets
13:33is through mechanical instruments that are called gimbals.
13:37And these are effectively articulating arms that, upon swinging them,
13:41could help you direct and steer the rocket as it's flying through space.
13:47The original gimbal design has been modified to match the power of new rocket engines
13:52with incredible capabilities.
13:54Private aerospace company SpaceX is pushing boundaries with their Raptor 2 engine,
13:59which produces over 230 tons of thrust.
14:03Raptor 2's gimbaling range is extremely impressive, 15 degrees on the Y and Z axes,
14:09which makes it ideal for specialized flip and burn spacecraft landings.
14:14SpaceX has big plans for the Raptor 2, powering dreams of future space exploration.
14:20In the early days of Goddard's experiments and the sophisticated rockets of today,
14:25a major development in their technology came when these powerful machines
14:29weren't used as a vehicle for exploration, but tools of war.
14:34In the Second World War, we see the introduction of long-range ballistic missiles.
14:39So these are, you know, still Earth-bound rockets, but able to cover a great distance.
14:44They're not guided. You can kind of send it on a particular trajectory,
14:48but ultimately you can't really pinpoint exactly where this bomb is going to strike.
14:54During World War II, the development of rockets became top priority for Nazi Germany.
15:00V-2 rockets were capable of traveling at supersonic speeds with such extreme arcs,
15:06with no warning for those below, making them impossible to defend against.
15:11Over 3,000 V-2s were dropped during World War II,
15:15resulting in the deaths of an estimated 9,000 civilians and military personnel.
15:21The V-2 was really a huge change in technology.
15:24It was man's first step in really being able to go into space.
15:29While there were solid fuel rockets that came before it, solid fuel isn't controllable.
15:34You can't turn it off and on. Once you put the match to it, it's gone.
15:39With the V-2, you suddenly have a controllable system.
15:43You can control the rate of fuel flow.
15:45You can control the amount of thrust that you get from this vehicle.
15:49So we're taking the first baby steps towards modern rocketry.
15:54Post World War II, we see the advent of the intercontinental ballistic missile.
15:58Basically, we can send missiles in suborbital trajectories
16:03and deposit payloads on the other side of the world.
16:06The Russians, after developing ICBMs, realized that space was somewhere they could reach.
16:12To that end, they launched Sputnik.
16:14Sputnik was the first man-made satellite of Earth.
16:18Basically, we were able to launch a very small object into space
16:23that was able to send a radio signal back to Earth
16:26to show that it was in orbit, that it was going around Earth.
16:29It's really a huge milestone.
16:31Everything before that was essentially still bound to the Earth's gravitational field.
16:37We now are able to put something into space and keep it there.
16:41The U.S. sees the Russians taking these steps and says,
16:44we have to match, and we have the space race.
16:47And that starts the Mercury Astronaut Program.
16:50We're basically going to try and send people into space.
16:53After experiments sending animals into space, including fruit flies, dogs, and chimpanzees,
16:59the first humans arrived in space in 1961.
17:02Russian cosmonaut Yuri Gagarin and American astronaut Alan Shepard.
17:07The first space race was a race for national pride, country versus country.
17:12Today, the landscape looks much different.
17:14It's become a billionaire's game.
17:17Now private companies in the same country are competing against each other
17:23in terms of sending satellites.
17:25So it's a little bit of change,
17:27and it's probably because of the different needs we have these days
17:32in comparison to a few decades ago.
17:35And so, as with anything, competition hopefully makes things cheaper,
17:39but competition hopefully also leads to ingenuity.
17:42In March 2002, billionaire business mogul Elon Musk founded SpaceX
17:47with the aim of revolutionizing the space industry.
17:50Otherwise known as Space Exploration Technologies Corporation,
17:54this startup rocked the world with the launch of its first Falcon Heavy rocket.
17:59The Falcon Heavy's Merlin engines use RP-1,
18:02a highly refined form of kerosene and liquid oxygen,
18:05as propellants in a gas generator power cycle.
18:09Chemical propulsion engines and rockets work by mixing two chemicals,
18:13fuel and oxidizer, in a combination chamber to create a violent reaction.
18:17Despite how far this technology has evolved,
18:20companies today are still using the same principles of chemical propulsion
18:24that were used to fuel Goddard's tests and the space race decades ago.
18:28The Falcon Heavy was a really important proof of concept
18:30for showing that we could take something really massive
18:33and still propel it into space.
18:35The Falcon Heavy is the second most powerful rocket in operation right now,
18:43just behind the Space Launch System, or NASA.
18:46The Falcon Heavy opens up a whole lot of doors in terms of what you can do.
18:51So if you have, you know, your regular Falcon 9 rocket,
18:55and that will allow you to get a certain payload into Earth's orbit,
19:00you know, that's great, but you need a much bigger,
19:02a much heavier rocket to be able to get beyond that.
19:06Another reason why the Falcon Heavy is such a major player
19:10in the space exploration industry is the low cost for launch.
19:14A Falcon Heavy launch runs 97 million USD.
19:18In contrast, NASA's Space Launch System is expected to cost 4.1 billion,
19:23Though NASA's SLS is taller and has a slightly larger payload,
19:27the difference in the price tag is out of this world.
19:30The modern space race is motivated by private companies
19:34with their eyes on the future of turning space transportation
19:37into a thriving business,
19:39and it's given us a lot of progress in a short amount of time.
19:43While it's one thing to successfully launch rockets carrying cargo and supplies,
19:47launching humans safely into space is a whole other ballgame.
19:51Since who goes up needs to come down.
19:54As rockets descend through the atmosphere,
19:57they're forced to contend with increasingly dense air.
20:00As they collide with the rocket, air molecules are compressed and heated,
20:04generating friction and heating up the vehicle's surface.
20:07The faster the rocket descends, the hotter it gets,
20:10a major challenge that could result in structural damage
20:13and critical systems failure.
20:15The angle of reentry is critical.
20:18If you come in too shallow, you end up skipping across the atmosphere
20:22like a pebble in a pond.
20:24If you come in too deep, you're not slowing yourself down enough
20:28to not explode in a big fiery ball upon reentry.
20:32So when we look at how capsules come back into the atmosphere,
20:36they're coming back with their largest surface area facing the atmosphere.
20:40The upper parts of the Earth's atmosphere are very thin.
20:43There isn't a lot of atoms there to interact with.
20:46But we want to interact with as many of them as possible
20:50because they're what's going to slow down our spacecraft.
20:53So having that big blunt area with an ablative material
20:57that's really resistant to heat
21:00allows us to use the friction in the atmosphere to slow us down,
21:04to get us below those orbital velocities
21:07so when we get down into the deeper, thicker parts of the atmosphere,
21:11we don't have all of that kinetic energy, all of that speed.
21:15Traditionally, when we've built capsules, we've used ablative materials.
21:19Basically, these are materials that, when exposed to heat,
21:22break up and expose more material below it.
21:25So they're kind of semi-sacrificial.
21:28We lose a bit of the first few layers to protect the inner layers.
21:32So that ablative coating or that ablative heat shield
21:36gets consumed during the descent to Earth.
21:39What a heat shield does is it essentially takes the brunt
21:42of all that stress and strain and that heat
21:45that the craft is experiencing
21:47such that it doesn't travel through the rest of the rocket.
21:50Some of the materials that can handle such high heat,
21:53we have to start off with ceramics.
21:55When you have a ceramic plate and you put something hard,
21:58the bottom doesn't get hard so fast
22:01because ceramic doesn't conduct heat
22:04as much as a metal plate does or a metal container.
22:07So they can resist heat a lot,
22:09and they can be customized shapes to deflect heat.
22:12So when you're coming down this drag,
22:15it's heating this from the friction,
22:18and the outside's solid.
22:20If it doesn't move the heat to the other parts,
22:23you're okay on the inside.
22:25Rockets like the SpaceX Dragon spacecraft
22:28use a PICA-X heat shield for its thermal protective system.
22:32PICA stands for phenolic impregnated carbon ablator,
22:36a special material capable of withstanding higher temperatures
22:39and providing better insulation.
22:42The Dragon also uses thermal blankets and control coatings
22:45to ensure its components remain at safe temperatures,
22:48protecting the vehicle and its passengers.
22:51Today's missions would not have been possible
22:54without NASA's Gemini program created in 1961.
22:58The Gemini program was conceived
23:01when NASA officials realized that there really needed to be
23:05an intermediate step between Project Mercury,
23:08which the stated goal was just to, you know, get a man into space,
23:12and then the Apollo program, which is putting people on the moon.
23:15And there are a lot of steps that needed to happen
23:17in between those two things,
23:19and the Gemini program kind of fits squarely in that.
23:22They experienced the first spacewalk,
23:25the first docking in the space,
23:27and the first recovery of a spacecraft in the sea.
23:31The computer science part of it was tricky
23:33because computers in the day were large
23:36and you couldn't put them on the vessel,
23:38so you actually needed to have a lot of the work happening on the ground
23:43and then that transmitted up into space.
23:45Landing a spacecraft is extremely hard,
23:48especially one like Gemini,
23:50where it's not a rocket that you can easily steer.
23:53So we came up with this idea that we can just launch this into the sea.
23:57And so we learned how to quickly get to it
23:59and how to quickly get the occupants out.
24:01The Gemini spacecraft boasted a revolutionary re-entry control system,
24:06rendezvous and docking capabilities,
24:08as well as improved life support allowing for longer stays in orbit.
24:13The Gemini space program was instrumental in proving
24:16that we could have prolonged stays for human crews in space.
24:20So whenever you launch a human into space,
24:22you have to take their entire living environment along with them.
24:26All the infrastructure that we take for granted here on Earth
24:29has to be provided artificially in space.
24:32The Gemini missions paved the way for future complex missions to space
24:36and new players are hoping to get into the game.
24:39The shifting regulations around space travel
24:42have opened up possibilities for countries like Canada,
24:45which previously relied on other nations for their orbital space flights.
24:49Today, only the United States, Russia and China have launched humans into space,
24:54but more countries are planning to add their names to the list.
24:57In 2023, Canada announced a new plan
25:00to support privately built rocket launches in the country
25:03as global demand for space-based services grows.
25:07India is hoping to be the next big player,
25:09using the recently upgraded Satish Dhawan Space Centre for their rocket launches.
25:14Originally built in 1979,
25:17the SDSC got a second launch pad in 2005,
25:21allowing multiple launches in a single year.
25:24With the design of the Gaganyaan crewed orbital spacecraft,
25:28India could be sending three people into Earth's low orbit
25:31for up to seven days in the not-too-distant future.
25:34But another country has their sights set far beyond Earth's low orbit.
25:38US-based NASA has completely overhauled its older systems
25:42to support future re-entry after trips to the Moon
25:45and one day Mars in their Orion capsule.
25:48NASA's Orion spacecraft is the newest generation
25:51of re-entry vehicles designed for today's space travel.
25:54It's built to withstand temperatures of 1,700 degrees Celsius
25:57and speeds in excess of 40,000 kilometres per hour.
26:01The Orion space vehicle is really designed to get us to the Moon and Mars,
26:05but it still has to come back through Earth's atmosphere,
26:08so it still needs the same systems that older capsules have,
26:13but what we've done is made it more robust.
26:15We have better heat shields. We have better ablative materials.
26:18We also now have automated systems to control the trajectory
26:22and attitude of the capsule so that it's hitting the Earth's atmosphere
26:26at precisely the right angle to minimize the amount of heat generated.
26:30So we've already sent machines to Mars.
26:33They're now roaming the surface, so we could say, for example,
26:37that Mars is the only planet that is controlled by robots
26:40or that is entirely inhabited by robots.
26:43And so we know that there is a way in terms of propulsion to get there.
26:47The primary bottleneck is how humans would survive such a journey.
26:52And that matters because if we ever want to have a chance of exploring space,
26:57we need to bring ourselves, the food that we'll need,
27:01and all the resources we'll need to do that space exploration safely
27:04and come back to Earth.
27:06And if it takes months to get to Mars,
27:08we will physically need the resources to survive for all those months,
27:13not just the equipment or gear of the rocket ship.
27:16China is also making strides in the reusable rocket sector.
27:20In 2022, engineers at the Chinese Aerospace Science and Technology Corporation
27:25perform their first tests on their 130-ton thrust engines, the YF-100N.
27:32These engines will be used in the next generation of launch vehicles,
27:36including a new reusable rocket for launching a crew
27:39to the new Tiangong Space Station and eventually the Moon.
27:43Plans for the first test flights will begin as soon as 2026.
27:47Much of today's excitement in space exploration
27:50stems from the original lunar mission.
27:53In the early 1960s, American President John F. Kennedy
27:56threw down the gauntlet to get us to the Moon.
28:00We choose to go to the Moon in this decade and do the other things,
28:04not because they are easy, but because they are hard.
28:08The Apollo 11 spacecraft was made of three components,
28:11the command module, service module, and the lunar module.
28:15The actual launch vehicle itself is three stages,
28:18and when this vehicle actually launches, it can barely get off the launch pad.
28:22Then as it starts going, it burns fuel at an immense rate,
28:26and we actually drop the weight of that first stage off
28:29and go to a second stage, and that continues to accelerate this rocket.
28:33And then we drop that second stage off and fire a third stage,
28:36and we're finally getting into orbit.
28:38The Apollo spacecraft was made up of three different components.
28:40First we had the command centre, which was the living quarters for the crew.
28:44And then we had the lunar module and the service module.
28:47The importance of the Apollo 11 mission and actually landing humans on the Moon
28:51was immeasurable.
28:53The inspiration that this led to countless people, future generations,
28:57we're still building off of this momentum in today's space travel.
29:00The command module is where all the controls are,
29:03and for the most part, the living space for three astronauts.
29:07The service module is where you will find the engines.
29:10And then there was a lunar lander.
29:12And so in the rocket, the three of them are stacked.
29:15Once they reach Earth's orbit,
29:18the command module and service module need to separate from the lunar module.
29:24The lunar module is then flipped around, and then they unite.
29:29Once they get to the Moon,
29:32the lunar lander then detaches from the command module
29:36and proceeds to land on the Moon.
29:39During the lunar module's final descent,
29:41an automatic landing system guided Apollo 11 astronauts towards the Moon
29:46before Neil Armstrong took manual control, piloting the module,
29:50using four clusters of rockets to finally touch down.
29:53Four hours later, Armstrong would say the words that changed the world.
29:58That's one small step for man, one giant leap for mankind.
30:04For Apollo 11's return flight,
30:06the module was propelled back into lunar orbit by its ascent stage rocket engine.
30:11After it rendezvoused and docked with the command module,
30:15the lunar module was jettisoned.
30:17Right before reentry into the Earth's atmosphere,
30:20the service module separated from the command module,
30:23left to burn up in the atmosphere.
30:25Building on this success, NASA went on to complete six Apollo missions,
30:29landing a total of 12 astronauts on the Moon between 1969 and 1972.
30:35After the Apollo missions, lunar exploration lay dormant for several decades.
30:40Today, NASA's Artemis program is grabbing the attention of people everywhere,
30:45promising to return astronauts to the Moon by 2024.
30:49This modern-day Moon landing will set the stage for a human mission to Mars.
30:54It's 200 times further than the Moon at the closest approach to Earth.
30:58Engineers and innovators are looking to cutting-edge technology
31:01to reach this new frontier.
31:04One potential development for rocket fuel is nuclear thermal propulsion.
31:09What's really cool about this is it would use nuclear power to use hydrogen, still,
31:14but have it be a much more energetic and violent reaction.
31:18So that would basically mean we're getting even more fuel efficiency out of hydrogen fuel.
31:22You wouldn't use nuclear thermal propulsion for the actual launch.
31:27But the upper stage, you could.
31:29It would be much more practical for getting between space destinations.
31:33Nuclear presents a really interesting opportunity for space travel
31:36because we're always going to be working against needing to take
31:39a large number of resources to be able to get even further into space.
31:43So nuclear, allowing for hydrogen as a fuel to be even more efficient,
31:47means that with nuclear, we can get further on the same amount of fuel.
31:51We've already found ways to use nuclear as a propulsion system on Earth,
31:56and that is submarines.
31:58And so perhaps there's a lot that engineers and scientists don't necessarily need to relearn,
32:02but that they could borrow from having designed those types of systems.
32:07It's not to say it's not a challenging feat to put a nuclear reactor up in space
32:11where it would be exposed to the massive forces of launch,
32:15the G-forces and the shocks that are going to come with it.
32:19In January 2023, NASA announced a collaboration with DARPA,
32:24the Defense Advanced Research Projects Agency,
32:27to demonstrate a nuclear thermal rocket engine in space by 2027,
32:32a critical step towards crewed missions to Mars.
32:35With nuclear thermal propulsion, getting to Mars could take as little as two months
32:40instead of nine, but the idea of using nuclear propulsion power isn't entirely new.
32:46DARPA and the Soviet space program spent decades researching nuclear propulsion during the space race.
32:52Despite some promising results, nuclear propulsion systems didn't really take off.
32:57There were many safety concerns around the application of nuclear power,
33:01especially after the Cold War.
33:03But the growing environmental concerns of the 21st century
33:06have aerospace engineers looking to reignite nuclear research
33:10in hopes of finding more sustainable solutions.
33:13The key to space travel is finding the right balance between power and safety.
33:17The possibility of creating stronger engines capable of further and faster voyages
33:22needs to be weighed against the potential dangers to the vehicle, passengers and the environment.
33:27While some teams are devising the next generation of green propulsion,
33:31others are focused on how they can cut costs and pollutants
33:34by simply reusing what they already have.
33:37After the Apollo mission, NASA realized that launching vehicles into space was extremely costly.
33:43At the time, the Apollo mission was the most expensive thing ever undertaken by mankind.
33:49Reusable rockets present a really important solution
33:52to minimizing the negative environmental effects that we have in space.
33:56So imagine you're trying to take a trip across the country and you drive your car there.
33:59Once you get to your destination, imagine taking your car and just throwing it away.
34:03That's going to be terrible for the environment and it's going to be very expensive to you.
34:06We would do a lot of precision machining to build these propulsion systems
34:12and then we would just one time use them up in space and leave them there.
34:17Another potential environmental impact is what the amount of space debris that we are leaving in space
34:22is going to have an effect on in the future.
34:24There's a large field of debris from old pieces of equipment, obsolete satellites
34:28that are over time only going to pose a greater and greater threat
34:32to us trying to launch a rocket through them.
34:34And that's where the idea for the space shuttle comes up.
34:37Let's try and make something that's reusable,
34:40that we don't have to build a new one every time we want to launch into space.
34:44We basically have a reusable space plane attached to a large fuel tank and solid rocket boosters.
34:51Getting the space shuttle up into space, you strap it to the side of a rocket
34:55and it's the rocket that goes up into space and the space shuttle at that point is just baggage.
34:59The space shuttle functionality is all designed around what's required to safely bring it back down to re-entry.
35:05You need to get it first of all through the deceleration that occurs during re-entry safely
35:10and then you need to have sufficient amount of maneuverability to be able to land as a glider would.
35:16But high operational costs and major safety concerns following the tragic Challenger
35:21and Columbia shuttle disasters led to the space shuttle program's retirement.
35:26The space shuttle was really envisioned to be a low-cost system.
35:29In essence, it never ended up achieving that.
35:32The cost of maintenance was something they didn't expect because when the space shuttle went back,
35:38there was a lot of damages and the maintenance was really expensive.
35:43It also had a number of failures.
35:45Obviously the system was very complex.
35:47To work correctly, everything had to go perfectly.
35:50And what we saw is when even small things go wrong, we can have disasters.
35:55In 1986, seven crew members died on the space shuttle Challenger
35:59during a routine mission just 73 seconds into flight.
36:03The failure of one of the solid rocket boosters led to a rapid destruction of the entire shuttle.
36:08Tragedy struck again in 2003 when the space shuttle Columbia broke apart upon re-entry into the Earth's atmosphere,
36:15killing all seven crew members on board.
36:18The Challenger and Columbia disasters were a major tragedy that had a profound impact on NASA,
36:24the space program, and the entire country.
36:27In the aftermath of these disasters, NASA worked to improve the safety of the shuttle,
36:32but it soon became clear that future galactic explorations would need a brand new spacecraft.
36:37Since the end of the space shuttle program in 2011,
36:40NASA has relied on Russian rockets to take American astronauts to the ISS.
36:46The space shuttle program really was a wonderful idea.
36:50It did provide a huge amount of science and understanding for mankind,
36:53but it was costly and we needed a change,
36:56and that's why NASA decided to move away from the space shuttle program to other programs.
37:02If it weren't for the interest and investment of private companies,
37:05the era of reusable rockets might have ended right then and there.
37:09But only one decade later, we have multiple companies possessing their own reusable rockets
37:14in a new era of competition and creativity.
37:17Primary use of space at the moment is communications technology,
37:21and there's been a significant shift from having small numbers of stationary satellites,
37:28stationary in the sense that they hover over one location in space as the Earth rotates.
37:34They have to be out at relatively large distances from the surface of the Earth,
37:38to the concept of having many, many more smaller communications satellites in low Earth orbit
37:45that then rotate around and they're constantly changing their position relative to the surface of the Earth.
37:50So that leads you to launch a lot of these things,
37:54and so you need to have reusable rockets in order to be able to make that process effective and efficient.
38:00If we can reuse a $60 million launch vehicle 10 times,
38:05instead of that launch cost of disposing of the rocket being $60 million every launch,
38:10we're down to a $6 billion cost.
38:12And all of a sudden, the cost to send satellites or people into space comes way down.
38:17The first company to bring reusable rockets back to the forefront was SpaceX.
38:22When SpaceX was founded in 2002, it promised reusability, lower launch costs, and easier access to space.
38:29This was the first time in history that a reusable rocket had returned to Earth and was recovered intact.
38:35In 2017, the same Falcon 9 rocket was reused and successfully launched.
38:40SpaceX sort of questioned this concept of disposable rockets,
38:45and they said, hey, if we could just figure out a way to recover those rockets,
38:48the ones that we spent so much time and energy building down on Earth,
38:52and bring them back down and reuse them,
38:54we'd save all that additional cost of machining and engineering.
38:59So SpaceX promised to the world that they'd be able to massively cut down the costs of space travel.
39:05There's a lot of failures, of course, we expect in such projects,
39:10but finally when you see, for example, SpaceX could successfully land the rocket,
39:16it's a really exciting moment for everyone to see.
39:20Well, I think the first time that you see these stages kind of land on the barge,
39:24it just looks so, it looks so improbable.
39:28Some of the important design elements of the Falcon 9 rocket are that it actually reserves a little bit of fuel
39:33for its own thrusters that it can then use to control its descent.
39:37The other way that they accomplish this feat is by having a few heat-resistant fins
39:43that help with the steering of the rockets as it descends.
39:47And then once it's going to interact with the landing pad,
39:50it has four shock-absorptive legs that help minimize that final push toward the Earth.
39:56SpaceX began expanding its reusable rocket fleet
39:59to include the much larger Falcon Heavy and reusable Dragon spacecraft
40:03for missions to the International Space Station.
40:06SpaceX was the first one to take American astronauts back to the ISS from American soil,
40:11and that happened in 2020.
40:13We're coming up to almost six crews delivered to the ISS by Dragon spacecraft.
40:19NASA has calculated that commercial launch costs to the International Space Station
40:23have been reduced by a factor of four over the last 20 years.
40:27When we look at space historically, the costs of mankind going to space have been literally astronomical.
40:34In the last decade, we've seen a revolutionary change in rocketry.
40:39The cost to launch vehicles to space has come down in orders of magnitude.
40:44We can now launch very small satellites, which provide huge amounts of information at really low costs.
40:52It's bringing the technology of space to the average person.
40:57There's companies who are sending up fleets of hundreds of tiny CubeSats
41:01to take pictures of the world every day.
41:03These small satellites provide farmers with the ability to see if there's a part of their field
41:08that's experiencing drought or blight, or help engineers determine
41:12if the slope of a mountain is becoming unstable and a landslide is likely.
41:17So it's really making space accessible for even small and medium-sized companies.
41:23It's not a huge cost to go to space anymore.
41:26As costs of rocket launches are drastically reduced,
41:30this increases the potential for civilian access to space, ushering a new era of celestial tourism.
41:36Predictions that space tourism could become a multibillion-dollar industry within the next decade
41:41have spurred on a sequel to the space race of the 20th century.
41:45Except now, the contenders are private companies seeking to send civilians out of Earth's atmosphere.
41:51One of the biggest competitors is Blue Origin, a company focused on suborbital space tourism.
41:57Owned and founded by Amazon founder Jeff Bezos,
42:01their first reusable rocket, the New Shepard, launched and landed in 2015
42:06and had its successful reuse occur in 2016.
42:10Historically, we've seen a few space tourists go into space.
42:14The first ones would go up on the Progress modules with the Russians to the International Space Station.
42:19More recently, we've seen New Shepard.
42:21New Shepard is one of the vehicles that's able to get people to space for a relatively short period of time.
42:27This launch vehicle takes people up for a suborbital trip to space.
42:31So basically, this takes you up into space.
42:34You get a few minutes in space to enjoy weightlessness,
42:38see space outside of our atmosphere and then return back.
42:42But it's a little bit different than other space systems that have taken people to space
42:46because this vehicle is reusable and it lands vertically.
42:50SpaceX's Starship is the next evolution in space launch systems.
42:55If it is successful, the Starship could do for space tourism what the Falcon 9 did for reusable rockets.
43:01This could be the first large-scale reusable commercial rocket,
43:05taking droves of tourists to space and back.
43:08In the future, a trip to space may be as common as a tropical vacation.
43:13However, before we can rush out and book our holiday amongst the stars,
43:17it will be important to have access to fuel in space.
43:20Asteroid mining could offer such a solution.
43:23The biggest thing keeping mankind from being successful in space is the amount of energy it takes to get things into orbit.
43:31So right now, we have to have a huge rocket to get mass into space,
43:36to build a space station or to go to Mars or go to the moon.
43:40But around us in space are metallic asteroids.
43:44These are nickel-iron asteroids, and they contain an immense mass of usable material
43:50that we can use to construct things in space without having to expend this huge amount of fuel and energy in getting it there.
43:57We go from having to bring that mass up into space to simply harnessing it from what already exists in space,
44:05allowing us to travel further and further along.
44:08Amongst all the minerals that can be found in those planets, the most valuable one for us is water.
44:15Now, when we have access to water, we can generate hydrogen from it,
44:21and hydrogen can be used as the source of the fuel for the rockets.
44:27Using earthbound mining techniques in space is a major challenge demanding cutting-edge innovation.
44:33Mining in this space is very different from the mining we have here.
44:37We need completely new instruments to be used over there because the gravity is different.
44:45Some forward-thinking companies are exploring an incredible concept called optical mining,
44:50touted as the most feasible way to mine materials in space.
44:53The process is like holding a giant magnifying glass to an asteroid and drilling a hole with the beams of sunlight.
45:00We don't even have to touch the surface of an asteroid to dig holes in it.
45:04So it is the magnifying glass. It's concentrating the rays of the sun into a focal point.
45:08And an unhindered electromagnetic wave, you can actually create a blast that is enormous.
45:15If we can achieve this asteroid mining, we can basically use each asteroid as a refueling station,
45:24and we can travel from one asteroid to the other one and get refueled and go further and further.
45:31And basically we won't have any limitation in how far or how deep we can travel into this space.
45:38Technology-wise, we're getting to the point where we can explore space.
45:42We can go to the moon, we can go to Mars.
45:44Mars is our closest neighbor, but it's also 20 light minutes away.
45:49You want to phone Mars, you won't have a problem on your spaceship when you get to Mars.
45:53You call back to Earth, it takes 20 minutes for the signal to get to Earth, just to them to hear something's wrong.
45:59And then 20 minutes for that signal to come back to say, do this.
46:02That's too long.
46:04When people go out into the outer solar system to Mars and beyond, they're going to be on their own.
46:09We have to design and engineer systems that are resilient,
46:12that can sustain people for months and years at a time in complete isolation.
46:17Yes, you can have a conversation, but it's a broken one.
46:20So you have to really be able to do everything yourself.
46:23However, there's still the problem of how to get us from the ground into space safely
46:27without being strapped to what is essentially a large bomb.
46:31Some concept vehicles for space tourism are turning away from the traditional rocket system
46:36and towards Earth-like devices that could bring us closer to the stars.
46:40In the future, space tourism could evolve into elevators.
46:44Using a table anchored to the Earth's surface,
46:47the space elevator would consist of a cable stretching to a counterweight in space.
46:52The cable would be held taut by the centrifugal force generated by the Earth's rotation.
46:57Electric cars would travel along the cable, transporting people and cargo into orbit.
47:03This would eliminate the need for rockets altogether,
47:06making space travel accessible and affordable for all.
47:10If you stand in one spot and have a yo-yo in your hand and spin, and you spin fast enough,
47:15the yo-yo will rise up and stay in a circumferential orbit around you as you spin.
47:21Well, the same thing happens in Earth's orbit.
47:24If we put a mass in orbit and attach a string back to Earth,
47:28and we have that mass in space be in geosynchronous orbit,
47:32basically, we now have a string attached to an object in space.
47:37And the idea with a space elevator is that we can then attach basically a cab to that string
47:43and pull it up just like an elevator to that object in space.
47:47This has the potential to revolutionize space travel.
47:50Basically, it becomes free to go to space.
47:52We can move relatively large masses into space.
47:55We can move people up relatively easily.
47:57The problem with this is we really don't have a material that's strong enough.
48:02So maybe someday we'll find some miraculous material that allows us to build space elevators.
48:08If we can, it's going to make space essentially an everyday thing.
48:12We'll be able to hop on an elevator, and 20 minutes later, you're in outer space.
48:17Ideally, if space travel were to become more common,
48:21it would require that you're able to launch humans into orbit without subjecting them to very high g-forces,
48:28which means slower acceleration and propulsion, probably more costly, but nonetheless would be safer.
48:36Such concepts like space elevators and balloon capsules are very theoretical,
48:41with many problems that still need to be solved.
48:44In the more immediate future, novel innovations like space sails
48:48could be a cost-effective way to capitalize off of the free solar power in space
48:53to move objects after the initial launch.
48:56Solar sails are an interesting concept,
48:58but it's based on a very simple phenomena that we mostly ignore on Earth,
49:02and it's this conservation of momentum theory.
49:05And when we think of light, it's hitting us, and we don't feel that,
49:09but that light has momentum.
49:11It's traveling from the sun if we're outside, and then it's hitting us on Earth.
49:16The sun is a ball of fire.
49:20These are gases, hydrogen, helium.
49:23When you pop the electron out, it becomes an ion,
49:26and that's all the sun is doing, constantly.
49:29So it's spewing out these ions of particles with high energy coming in towards Earth.
49:36Most of these burn in the atmosphere.
49:38Earth is a blanket of atmosphere that disperses, reflects, kills, absorbs all these ions.
49:48We get the light through, but we get filtered off with the ions and the plasma particles
49:54and the high-energy particles that are floating in space and bombarding the Earth every second.
49:59If you have a piece of equipment that's out in space,
50:02away from all air currents and gravity,
50:05and it gets hit with photons coming from the sun,
50:09it will feel it like a sail in a sailboat.
50:12The amount of force being given per photon is very small,
50:15but in space, it's a vacuum,
50:17and so you don't require anywhere near the same amount of force
50:19to actually put something into motion.
50:21As we have a spacecraft that deploys a large sail in space,
50:25that sail just continuously accelerates that spacecraft over time.
50:30Anytime we can harness something from space to power our needs,
50:35it just means we don't have to bring that thing up with us.
50:39It's kind of diminishing returns, though,
50:41because you need a really, really big solar sail to collect enough propulsive energy
50:46to absorb enough photons to give you that movement.
50:49So if you're talking about pulling a space capsule through space,
50:52you're talking about a solar sail that's probably the size of a U.S. state.
50:57Like, we're talking about immense surface areas.
51:00It's something that's doable, and we're certainly looking at it,
51:03and it's a technology that's actually been proven.
51:05So we've actually sent micro cube satellites into space
51:08that have shown that solar sails actually work.
51:11So we're taking our first steps down that road to solar sails.
51:15How practical they become in the long run is still yet to be seen.
51:19What excites me the most about the concept of the current space travel
51:24and the current race and the desire of people to go to space
51:29is the fact that in order to accomplish those desires,
51:32we're going to come up with new technologies.
51:34And those technologies are going to solve a lot of practical problems here on Earth.
51:39The future of space travel is bright,
51:42and we've only scratched the surface of what's possible.
51:45Even as we reach further into our galaxy, the challenges are only getting greater.
51:50But the solutions could already be out there.
52:15NASA Jet Propulsion Laboratory, California Institute of Technology