so a b 51 mustang used drop tanks to fly to europe in world war ii, a critical element in this story. we do not have a drop tank. we're looking for one. those are the kinds of objects we want to improve our displays as well as to record the story of the technology, the people and the events. >> as general daily pointed out earlier, only a small percentage is here. you have more in storage than you're able to show. >> that's correct. we just have a certain percentage here at the national mall and at the hazy center. but it's quite a few of the artifacts are on loan or in storage. >> jeremy kinney, thank you very much for you time. >> thank you. >> happy 40th birthday. >> thank you very much. >> it's more than aviation, it's also space exploration from moon to mars as we continue our tour inside this museum. each week american artifacts takes viewers into archives, museums and historic sites around the country.

up next, we visit the smithsonian national air and space museum, located on the national mall in washington, d.c. our tour guide is valerie neal, head of the space history department at the museum. who shows us artifacts that tell the story of space exploration, from the moon to mars. >> i'm valerie neal. we're in the boeing milestones of flight hall at the center of the museum. this is the hall where we display the spacecraft that transformed the modern world. when this museum opened in july of 1976, almost every space artifact on display had recently been in the news. this was very much a museum of contemporary space flight and it was for most people their first chance to see what had been lauded in the 1960s and early

1970s during this heroic age of space exploration. when the united states and soviet union began spending craft out to explore the nearby planets, all the of this was exciting, thrilling and people just flocked into the museum to see it. in the 40 years since the building opened, we have continued to acquire trurz of spa treasures of space history. we have thousands of artifacts related to space history. we have just over a thousand of them on display in our two locations here in the washington area. and then we have another 1500 on display in other museums around the world. in our tour today, we're going to look at some of the original

artifacts that were the stars of the show when the national air and space museum opened, and we're also going to look at artifacts from history that has been made since then. we'll start our tour right here, with the lunar module. the icon for the landing on the moon in july, 1969. it actually has a companion spacecraft, the apollo command module. and the command module, its service module, and the lunar module together carried three astronauts, neil armstrong, buzz aldrin and michael collins, to the moon. the command module very significantly also brought them back safely. this lunar module is an actual lunar module that never flew in space. it is lunar module 2. it was intended to be used in a

earth orbital test flight, but the test was canceled as unnecessary and so nasa transferred this lunar module to the national air and space museum. it consists of two parts. the base, which has the legs. and the rocket engine in it. and then the oddly shaped top which is the crew module or crew cabin. and this was attached to the command module for the flight from earth to lunar orbit. and once in lunar orbit, the two crew members who would descend to the surface, armstrong and aldrin climbed into the lunar module. it separated from the command module where michael collins stayed to orbit the moon and it began its descent down to the surface. >> 40 feet down, two and a half. picking up some dust. more forward. more forward.

drifting to the right a little. >> contact light. okay. engine stop. >> we copy you down, eagle. >> the eagle has landed. >> this was a thrilling moment in history and almost everybody who was alive at that moment remembered where they were, whether they were watching it on television in their own homes or if they were standing in an appliance store watching it on a television. people around the world stopped to watch the landing on the moon and the first steps of human beings on the moon. >> okay. i'm going to step off the land mount. that's one small step for man,

one giant leap for mankind. >> after the crew, the apollo 11 crew had climbed out, done some exploration close to the lunar module, collected some samples of lunar swale and rocks, taken some photographs, placed a u.s. flag on the moon, they went back into the lunar module and this became their vehicle for their trip home. they launched the small top partial leaving the base on the moon. they ascended back up into lunar orbit, rendezvoused with the command module again, exited the lunar module. once they were secure inside the command module, reunited with michael collins. the lunar module was detached and it fell back to the moon

with an intentional crash on the moon because geologists and seismologists wanted to track what kind of impact it made on the moon. so from a space historian's point of view, these two craft, the apollo command module and the lunar module are the icons of the space race. along with the suits worn by the astronauts on the moon, these symbolized that very historic moment in time, july 1969, when human beings first set foot on another body in our solar system. and in effect, won the space race. when children look at this spacecraft, they often say that doesn't look like a spaceship, because we tend to think that spacecraft are always

streamlined and maybe they look like rockets more than anything else. but this spacecraft has an interesting design and in many ways it's fairly primitive given the job that it had to do. it didn't need to be streamlined on the outside because it wasn't going to operate in the atmosphere. it would only operate in the vacuum of space. and it would not be subject to strong gravitational field on the moon. so it's actually fairly flimsy in some areas. the legs are obviously strong the mount for the rocket engine is strong, but the draft itself, and particularly the crew module or crew cabin, was really fairly spartan. it had two windows. neil armstrong had command of the craft during the final descent to landing. both of them were standing. they were fully suited in their space suit and they pretty much filled that interior volume in

that position with those space suits on. it was not really designed for comfort. it was designed for the purpose of landing, giving the crew an exit so they could spend a couple of hours on the surface of the moon and then launching again along with their precious cargo of lunar soil and rocks to bring back home to demonstrate that they had been there and to have those materials for scientists to begin analyzing to better understand the moon. it's also amazing to think that the computing power required in that day to send these craft to the moon and to program them for the descent and launch, was done with fairly primitive computer programs and memory was minuscule compared to the memory we have now.

it's often said that the computing power we hold in our hands every day with our smartphones is vastly more than it took to send people to the moon and back. it gives you a sense of the ingenuity of the engineers in that day to devise the solutions to get people to the moon and back safely. so we have seen the iconic artifacts from the heroic age of space flight in the 1960s. our next stop will be skylab and we're going to look at that returned to earth and be

launched again, returned to earth, with a human on board. by doing that in the year 2004, spaceship 1 won the x prize, a prize of $10 million that was posted to encourage commercial development of spacecraft that could be used for space tourism. spaceship one operates as a suborbital craft, it doesn't go into orbit around the earth, but like alan shepard did in 1961, it goes up, makes a loop into space, and then glides back down to a landing like an airplane would land. there is a mother ship that is the actual transporter aircraft, and spaceship 1 snuggles up under it. the mother ship is the one that flies it around here in the

atmosphere. and then it is released from that. and after it is released, it is when the rocket engine ignites and shoots straight up. spaceship 1 is a very innovative design in that it has a hybrid rocket that is part liquid propellant and part solid propellant. it can hold three people, though in its prize winning flights it had only the pilot. and some ballas t to indicate te weight of two other people. it has a very distinctive design. as you can see right now, it is in a configuration with its wings up at about, oh, 50,000 feet, 40,000 to 50,000 feet. those wings are down and it is very streamlined looking. but as it shoots up into orbit, and reaches that threshold of about 100 kilometers or 62

miles, the wings pivot up and that stabilizes the craft for that loop over in orbit. and the loop lasts about six minutes during which the pilot and many maths would be able to experience weightlessness. if they wanted to unbuckle their seat belt, they would rise out of their seats. they could look through the round windows and get a wonderful view of the curvature of the earth and the blackness of space. and then as the craft begins to descend, the feathered wings, what they're called, the feathered wings stabilize the spacecraft just the same way that the badminton birdie or a shuttle cock is stabilized so that the nose stays downward pointing and the whole craft stays stable. it also creates more drag and slows the spacecraft down more quickly so it doesn't need a

bulky heat shield. and so then as spaceship one comes back into the atmosphere, once it is in part of the atmosphere where there is enough air, that it can fly, aerodynamically again the wings pivot back down into that streamlined position. and the whole thing glides back down to a landing on the desert or on a runway. this little star-spangled craft, to me, is reminiscent of a race car. it is sleek. it looks aerodynamic. it looks speedy. it looks aerodynamic and it looks sporty. and it just looked like the kind of craft that a person who wanted to go up into space for a quick look and a quick experience of weightlessness might want to climb in and go for a ride. where this may go is to the next step, which is a larger

spaceship, too, and sir richard branson, who operates virgin or owned virgin atlantic airways, partnered with burt rutan and his company, scale composites to do a larger version of spaceship one. he's named it virgin galactic, and it will hold 12 people. and it is being developed for the express purpose of providing space flight to paying customers who want to have the experience of space flight. they don't have a set debut date yet. they suffered a real setback when one of their test flights crashed. but it's still out there on the horizon as something that's likely to happen. and virgin galactic is by no means the only such company. there are other companies who are developing spacecraft for the very same reason. and we may be on the threshold of a new era in human space flight. most of the spacecraft that are

in the collection of the national air and space museum come from our space agency. nasa is our principle donor, and at the end of nasa's need, the agency will transfer spacecraft, space suits, and a great variety of other equipment to the museum so it can be preserved and displayed and even used for research. spaceship one is a different case in that it came from private enterprise and so in this case, we work directly with the owner/manufacturer/designer, burt rutan and his business partner, paul allen, who is one of the co-founders of microsoft, and we approached them after the first flight in june of 2004 and said, regardless of whether you win the x-prize or not, we think spaceship one deserves to be in the national collection because

it was the first privately developed spacecraft piloted by a human being to go into space and return. you might notice there's a small dent in the nozzle of the engine on the back of spaceship one. and that is not damage that was caused by delivering it to the museum or suspending it from the rafters. rather, that buckled in space during its first test flight when the engine ignited and just the heat and the force of the engine ignition buckled the nozzle. for the second flight and the third flight, a different nozzle was used, and they also made some corrections to the ignition sequence so they didn't have that buckling problem again. but when we asked to have

spaceship one delivered to us for the national collection, we asked to have it returned to its original configuration from its first flight. the first flight wasn't the prize-winning flight, but it was the record-breaking flight. and so they went to the trouble to reinstall the dented engine nozzle on it. our next stop will be sky lab, and we're going to look at that because it is one of the original artifacts on display here since before this museum opened. sky lab is so large, it was brought into the museum before the building was closed out. now i'm standing in front of a model of sky lab that's as tall as i am but the real sky lab orbital work station behind me absolutely dwarfs the model and me. it reaches from the floor up

into the sky lights of this building, two stories tall. sky lab was the united states first space station, placed in orbit in 1973 and in 1973 and '74, three different nasa astronaut crews spent time aboard it. three men at a time, one group was there for one month. another group for two months, and the third group for three months. the whole point of the sky lab missions was to get some experience in living and working in space. when the apollo program came to an end, there was still some hardware left over. and nasa thought, what can we do with this? we developed this tremendous capability to launch spacecraft all the way to the moon. we still have a couple of powerful rockets on hand. can we repurpose them and do something else? so the decision reached was to

take the third stage of the gigantic saturn five rocket that powered the spacecraft away from earth on a trajectory to the moon and turn that into a habitable module, a sort of miniature space station that crews could live in while they were getting this experience of living and working in space. the actual element that's behind me is the full cylinder that is marked by this wide white band here. you can see from the cutaway there that it's two stories on the inside. those were two floors where the astronauts could actually live. in the missions to the moon and earth orbit, they had been in spacecraft that were essentially cockpits and had no more room than a sports car. but sky lab was like having a house, it actually had rooms.

there was a galley ward room where they could prepare food, meet around a table, eat together. they still were eating out of plastic bags and tin cans, but at least it was more home like and more sociable. they had sleeping quarters, three bunk areas about the size of closets but each member had a private area to retire for some solitary time and some sleep without being confined to the flight seat in a capsule and most important it had an actual bathroom. it had an actual toilet. in all of the previous missions, the little known dirty secret is that the astronauts were using plastic bags to collect their waste. but finally they had a toilet and didn't have to deal with the

mess of taking care of their bodily functions. it had a sink where they could wash up and shave. it even had a shower, it was essentially a tunnel like sheath that an astronaut pulled up around him and then could use water from a sprayer inside that container, but then the trick after the shower was all of the water had to be wiped off, wiped off the body, wiped off the little enclosure. they finally decided it took -- it was more trouble than it was worth. they would just take sponge baths. but there was also room for them to have an exercise bicycle and to have some experiments set up and then they had a huge attic above the living area where their extra supplies were stored

and a lot of the system's elements were there. it was so big that they could run track around the perimeter of it and do tumbling around the perimeter of it, just running and tumbling across the tops of the lockers. that was for fun but they used that space for serious reasons too and they were testing out a jet backpack that might be used on space walks and they were able to operate that in that attic space that was so commodious. then below their living deck floor, there was the remainder of one of the propellant tanks and that became their big trash can. there was a hatch and they could put their trash through the hatch and it would go down to that lower level. the orbital workshop then was the largest part of the sky lab space station but above it there was an air lock module that enabled them to go outside and service this big observatory the

solar observatory, which was a wonderful scientific facility attached to the orbital workshop. and using the instruments, variety of cameras and detectors on what was called the apollo telescope mount, we got our first really detailed views of activity on the sun. and we understood for the first time how dynamic our sun is and how it's just roiling with activity all the time and spewing out big explosions of matter and it has holes in it and it has storms on it. it was an amazing thing to get this new information through the telescopes on sky lab. then here at the top, one can

see the docking port for the apollo command and service module, which was essentially the shuttle craft to bring the astronauts to sky lab and bring them back home again. this whole thing is 22 feet in diameter. and again, when you think of the ingenuity of turning a stage of a rocket which is basically a big fuel tank into a home that people can live in and provide them with plumbing and comfort and room to move around, a window to look out and enjoy the views of the earth, this was a kind of turning point in our space program. sky lab was the test run for what the next big thing was supposed to be. and from the late 1950s and early 1960s on, planners in the

united states had foreseen an eventual space station. in fact, the original plans were to build a space station in earth orbit first and then go to the moon, but president kennedy reversed that and decided to send the united states to the moon first as part of the cold war competition with the soviet union. in the back of everybody's mind there was still a space station. sky lab was the first step toward what now has become the international space station, a huge new facility in earth orbit. this behemoth behind me is actually the backup sky lab space station. it is flight ready. nasa built two of them in case they wanted to do two sky lab missions or in case there was some hardware problem with the first sky lab orbital workshop. we did make a modification to it. ordinarily we don't modify

flight ready hardware but in this case, we cut a passage way two doors into it, and laid down a sort of hallway right through the middle of this living quarter so people who visit the museum can walk inside sky lab, they can see the living quarters, they can look into the bathroom, they see a mannequin at the table with some food out on the table. the shower is set up there, the exercise bicycle in plain view, they can see the trash air lock right there. if they look up, they can just be wowed by the amount of free space there is. i mentioned that sky lab was occupied in 1973 and '74, the last crew to leave sky lab, buttoned it up and put it in sleep mode with a view towards a future crew possibly coming

back. and then nasa got busy developing the shuttle. so what happened to sky lab? well, gradually over time its orbit began to deteriorate somewhat and started dropping lower and lower. there was an early plan to use the space shuttle to go up and rendezvous with it and boost it back up to a higher altitude so that it could still be available for use. but the shuttle wasn't yet ready to fly. so what happened is after the orbit diminished, nasa had to bring this back in a controlled re-entry. in 1979, sky lab was brought back down and it streaked into earth's atmosphere like a meteor and broke up over the indian ocean. and a few pieces fell in parts of str

of australia and was recovered. but fortunately no one was hit, no one was injured, no property was damaged. now i paused here at sky lab because this was still news in 1976 when this museum opened. people streamed in here literally by the millions that first year. they were thrilled not only to see the old aircraft but to see the new spacecraft, to see what had been happening in space that they had seen on the news and heard about. and sky lab was one of these featured attractions. sky lab was about settling down in space. throughout the 1960s, the impetus had been to get into space, to get into orbit, to get to the moon. after the space race was won, by the united states with the landings on the moon in 1969 through 1972, both the soviet space program and the u.s. space

program began to shift gears. so as we built sky lab in the early 1970s, the soviets were also beginning to develop a space station. in fact, a series of space stations. called salyut. and there was a moment there in the early to mid-1970s when soviet and u.s. tensions abated somewhat, and the two space programs, the two nations, decided to do a cooperative venture in space, and that occurred in 1975. it was a rendezvous and docking in space of an apollo spacecraft from the united states and a soyuz spacecraft from the soviet union and it was billed as a historic handshake in space because when the two craft docked and opened their hatches

to this docking module between them, the american commander and the russian commander came together and shook hands. at the time, it was hoped this might be the beginning of a new era of cooperation in space, but that thaw in relations didn't last very long, and so really throughout the latter 1970s, 1980s, the u.s. went on with developing the space shuttle. the soviets went on with developing the series of space stations and then a much larger space station called mir. it wasn't until the collapse of the soviet union in about 1992 that another opportunity arose to have a cooperative relationship in space. at that point, the u.s. and its international partners, europe, japan, and canada, invited russia, the new russia, into

partnership on the international space station. and since then, our activities in space have been carried out on a cooperative basis. now we're in the moving beyond earth gallery. this is where we treat human space flight in the era of the space shuttle and the international space station. basically, everything that's depicted in this gallery happens since the museum opened in 1976. in fact, in that year, the first space shuttle, the test vehicle enterprise made its debut, and it was greeted as a revolution in spacecraft design. this was the first spacecraft to look like an airplane. the first reusable spacecraft that would be able to return to earth, land, be serviced, and fly again.

and really, the space shuttle era is all about practical uses of space. practical access to space. practical benefits from space. the distinctive feature of the space shuttle was that it was a reusable spacecraft, and by being reuseable, it was supposed to be more economical and more readily used for routine space flight. in fact, early on, the planners and designers thought it might operate as regularly as an aircraft in service. it didn't work out that way. it turns out even though it was a reusable craft, it was in many ways an experimental craft. it was a very complicated and sophisticated spacecraft. now, i'm standing in front of one of the distinctive features of the space shuttle, which is one of the three main engines that powered the craft into orbit. these are reusable liquid

propellant engines that had not been done before. they operate with a greater degree of efficiency and reliability than any other rocket engine had done before. the space shuttle main engines were one of the great technical challenges of the space shuttle program and we're fortunate to have one here that was made up for us of parts and components that flew on quite a variety of missions. and both as a whole, it wasn't flown in space. it has flight components on it, so we're very pleased to have that. we do have actually the space shuttle "discovery" on display at our second location near dulles airport. it was delivered to us without main engines. it was delivered only with nozzles because nasa chose to

save those engines. they were so highly prized. they chose to save them for possible use on the next launch vehicle. if we're lucky one day we may get one of those, and that would be one that had actually flown in space. on the wall behind the main engine is a cross section of the other main propulsion element of the shuttle. that's a slice of a solid rocket booster, or it's actually a slice of a model of a solid rocket booster. but in addition to the rocket engines that were physically integrated into the shuttle orbiter, there were these twin solid rocket boosters mounted on the sides of the giant liquid propellant tank. and we commissioned that model of the cross section to show the pattern in that rocket booster where the solid fuel first begins to burn.

and it's like a star shape or a snowflake-shaped pattern there. and that increases the efficiency of the fuel burn and produces a tremendous amount of thrust through the twin solid rocket boosters. they burned out within two minutes of ignition and fell away from the shuttle. the main engines consumed fuel from the external tank for eight and a half minutes, and the tank fell away just before the space shuttle entered orbit. a totally revolutionary way of sending a spacecraft into orbit. and that's really the theme of this whole gallery, is a new way of doing space flight. in the shuttle era, as i mentioned, the shuttle era began in a way in 1976 when this museum opened. the first actual shuttle launch

into space was not until 1981, but then for the 30 following years, there were 135 space shuttle missions, all but two of them completely successful. and the two that failed, of course, were the "challenger" and "columbia." accidents, the 25th shuttle mission, and then 107, in 2003. in talking about the shuttles in this gallery, we do talk about what was revolutionary about it. we also do acknowledge that it was not a perfect technical system. that it didn't perform exactly as planned, and it did result in those two tragedies. we didn't want to gloss over that. we wanted to make the point that doing something revolutionary always entails risk and working

with new technologies that are operating at really the far margins of performance adds to that element of risk. at the other hand, the whole space shuttle system consists of millions of components that had to work perfectly every time. and in most occasions, that's exactly what happened. we have a section in here about the design of the shuttle, the various options that were considered before the final design was settled on, whether to make it a fully reusable vehicle or a partially reusable. partial won out for economic reasons. we also talk about living and working in space on this shuttle. because the shuttle served various purposes. it was a delivery truck. it could carry satellites into orbit. it was a short-term space station, when a laboratory was

in the pay load bay, it actually served as a research center in space. it served as a servicing station, as with the hubble space telescope that astronauts could do repairs in orbit and prolong the life of the observatory there. and then finally, it was a construction site for the international space station. and all of the large modules, all of the solar rays, all of the long tresses that make up the international space station were carried up into space in the pay load bay of the space shuttle. the space shuttle also had a profound impact on the astronaut corps and on our perception of human space flight because up until that point, the astronaut corps had consists entirely of men, and the majority of them were test pilots. many of them also combat pilots

who were very experienced in high-altitude flight under extreme conditions. some scientists had been admitted into the astronaut corps and one of those scientists went to the moon, and three of them served on sky lab. but because the shuttle had a different kind of mission to do research and useful work in space, it needed a crew that was more versatile than just pilots. it needed scientists and engineers to carry out its missions. and once the astronaut corps needed more scientists and engineers, that opened up the pool of eligible candidates to become astronauts. and so in 1978, nasa selected its first astronauts for the space shuttle era. and they chose 35. of those 35, 6 were women, 3

were african-american men, 1 was an asian pacific heritage man, and from that point on, the shuttle astronaut program was much more diverse. and it became more reflective of who we are as the american people. and in 1983, within the first ten missions, a woman flew in space on the seventh mission, sally ride, and an african american flew in space in the eighth mission. guy buford. and we have on display in this gallery their flight suits that they presented to the museum after their historic flights. and certainly, sally ride became a hero to girls and women. she was one of six women in the astronaut corps. she happened to be the one chosen to fly first, and so she ended up being the one who got credit for breaking that barrier

and became a hero then for the rest of her life. guy bluford had the same effect on the african-american community. by the time the shuttle program ended in 2011, about 20% of the astronaut corps had been women. about 12% had been african-american. women and african-americans had served in every role. they had been pilots, commanders, space walker, mission scientist. they had demonstrated very well that people who are capable, who have the right skills and the right drive and motivation could be successful astronauts. the last big task for the space

shuttle was actually its original task, the task with which it was designed, with that large pay load bay, and that was construction of the international space station. it took about 40 missions to assemble the international space station in orbit. starting in 1999 and completing in 2011. the space station as it exists now is depicted here in the gallery in a model that we have suspended. it's a 1 to 100 scale model. the actual international space station is the size of a football field, from end zone to end zone and from sideline to sideline. that gives you a sense of this tremendous technological endeavor, to build something of that size in space. so, we have been in earth orbit for a few minutes. why don't we go to mars? just outside the gallery is viking, the first spacecraft to land on mars. here we are at viking, the first space craft to land on mars.

actually it's one of two to land on mars. this was another thing in the news at the time that this museum opened in 1976. to have landed on mars after a number of trials and misses was very exciting. both the russians and the united states had been trying to put a craft onto the surface of mars. this was equipped as a sort of observatory and a sort of laboratory. it had a scoop at the end of a long arm that was going to scoop up some soil near its landing site and dump it into a little container where it would be subjected to some chemistry tests to determine if there were any organic compounds in it or any moisture in it. anything that might have been

conducive to life. and in fact, in a very simplified version of things, the viking lander was going to look for signs of life on mars. that's how the public perceived it. the scientific community was interested in a whole variety of other questions. what was the composition of the rocks? what was the surface environment like? so it had a weather station, it had a variety of instruments. and this was the first chance to really touch and feel the surface soil and the surface rocks on another planetary body other than the moon. tremendously exciting in the beginning of what has become a long history now of returning to mars. each time with more sophisticated instruments. each time to learn more about

that neighboring planet which has long occupied people's imaginations as the likeliest next destination for human exploration. next destination for human exploration. landers like the viking lander opened the door toward that possible eventual human exploration of the planet mars. vikings i and ii at t he respective landing sites have been dormant for a number of years just sitting there on the surface of mars. waiting to be rediscovered by either a a rover or some eventual human explorer. this viking lander is a duplicate and this is kept at the jet propulsion laboratory in california. and in the mission, they used it

as a test case to try out any procedures to do trouble shooting for any problems that they detected with the surface land willers on mars. -- land erers on mars. so this lander is really part of that family. planetary exploration when it started in 1960s, we didn't know exactly where the moon was or mars or venus, and we knew approximately where they were, but you need to know that much more exactly if you are going to launch a spacecraft from planet earth, which is in motion, and the spacecraft will be in motion, and the planetary destination will be in motion. so there is a lot of calculation that goes into that. in the early 1960s and mid-1960s

a there were a lot of misses. we should shoot something towards the moon and it would sail right past or miss ut by a long shot. or the soviets would do the same thing or we would try to land something on the moon, and it would crash into it instead. and so it was kind of a demolition derby in the 1960s. but that was really the essential first stage, was to start sending craft out to fly by and to increasingly get closer and closer so that you could determine exactly where they were and what the celestial mechanics of space flight really were at an exacting level. so after the fly-by was perfected and the purpose of that was to get a good first look, cameras onboard could send back images, get a sense of what that body was like.

then, the next step was to send something to go into orbit around it. again, with cameras and some other instruments to try to determine what is the surface like. is there an atmosphere? what is it like? what more can we learn by being closer to it and staying in orbit around it? and again, there were some near misses on those orbiters as well. but by the early 1970s, that problem was pretty well solved. so you have fly-bys, then you go into orbit, then you ascend a lander. the next step is to send a rover so that you can learn about not only the immediate landing site where a static craft like viking sits, but you could start ranging out around it and start doing what human beings do, go exploring. extend the range. look around the next hill to see

what's there. so the next phase in our exploration of mars has been rovers and our next stop will be to take a look at three generations of mars rovers. now, we're in the exploring the planets gallery, where we really focus on recent events in planetary exploration. as we learned with viking, the strategy tends to move from having a static lander, which viking was, to having mobile landers. and this is one of my favorite parts of the museum because this is where we display the three rovers that have been doing major research on the planet mars over the last 20 years. the first rover to land and operate successfully on mars was one identical to this one. it was part of the pathfinder mission of 1996, and a little

rover named sojourner was put down on the surface of mars, and it operated long beyond its expected lifetime, exploring around in the vicinity. you can see it has six wheels, and they're a kind of wheel called rocker wheels that will enable it to go over rocks without tipping over. it's about the size of a microwave oven, if you imagined a microwave oven having wheels. it has solar panels on top to keep it powered. it was really a little geologist that was put down on the surface of mars to do some of the kinds of investigations that a human geologist would do. it's equipped with a device to touch up against a rock and determine what chemical elements are in that rock. it had a camera for guidance. it could also pick up

information about the ambient environment of mars. so you can think of marie curie is the name of this one. and sojourner as the first geologist to step foot on mars and to go roaming around so they could explore a broader area. this is actually the back-up to the pathfinder mission. this one could have gone to mars itself. ten years later, after the pathfinder mission, we had another mission that landed a somewhat larger rover on mars. and this is a model of spirit and opportunity. this is an engineering model, though, and isn't really ready to go to mars. you can see the growth since the first rover. this one is more like the size of a golf cart, perhaps. again, it has the special wheels so that it can operate well on the uneven terrain. and it's equipped not only with

the solar panels to keep it powered up, but with larger and more sophisticated instruments. it has a robotic arm that extends out. it has almost a head here at the front, at the top of this long neck. and that's where the cameras are for its movement around, enabling scientists here on earth to see where it's going and to see what it's seeing. and it has various other scientific devices on it, and again, a kind of mars weather station to determine what's the ambient environment like, what is the wind like, what are the temperatures at different times during the martian day. what is it like when a dust storm blows up? and passes through. so again, this is a more capable geologist now that's on the surface of mars.

but one that is mimicking some of the capabilities that a human being has. spirit and opportunity were launched to mars in the year 2004. and opportunity is still operating, still roaming around on mars, sending out good data, again, outliving its life. so now we'll have a look at the third rover that's on the surface of mars. and this one landed in 2012 and is still working today. this is a model of curiosity. curiosity has just grabbed public attention because first of all, it's so big. it's like having a car on mars. and this is the one that had the very dramatic landing sequence where it was dropped from a crane that was descending from

the orbital spacecraft. and it was called seven minutes of terror to get it down to the surface of mars without it being damaged. but it was a very successful landing. and curiosity has been roaming for kilometers on the surface of mars. it's studying planes. it's on the rim of a crater. it's going down into the crater to have a look at what the surface geology is like there. and the main mission of curiosity is to follow the water. scientists have a lot of evidence that at some point in the past mars had a lot of water. and the evidence is in sedimentation on mars and in portions of land that look as if they have been washed over by water which then evaporated. and so the thrust of the curiosity rover is to

investigate sites that seem to have had an abundance of water at some time in the past. once again, this is a surrogate for a human geologist, much larger in scale than the pathfinder and the spirit and opportunity rovers. much sturdier structure. a chassis that really is the size of a compact car. again, a suite of cameras and weather station instruments on board. and this one is also a chemistry lab. there are several devices on here that can do analysis of the chemicals in the soil and in the rocks. it's really being a very exciting mission. and it has no end in sight. i think the public has become very fond of these rovers because they sense that they are

surrogates for us and maybe pathfinders for us. they're doing the initial reconnaissance of the surface of mars so that if in the future humans actually go there, they'll know a lot more about the terrain and also know a lot more about sites that might still harbor moisture, if not actual water. and this pattern replicates what we did when we went to the moon. we started with missions that first flew past the moon. but one of the next things we did is set a lander on the moon just to determine how strong is the soil. can something land there, or will it sink in? if humans are going to land, will they be able to walk on the moon? and i think we're quite confident about mars that humans will be able to move around on

the surface of mars very well. the rovers have demonstrated how easy it is to do that. one other thing about the rovers is they don't operate alone and preprogrammed. there are whole teams here on earth that are charting out their itineraries and scheduling their activities. and when they are working on the mission, in their heads, they are on mars with the rover. and they even wear watches where they set their watch to martian time. the martian day is 24 hours and 39 minutes. so their day is just enough longer than ours that for the people working on earth, each day they start work 39 minutes later. the days creep ahead for them.

so when this museum opened in 1976, we were wrapping up a golden age of human exploration with the "apollo" missions to the moon, and we were launching into the first golden age of planetary exploration with the missions of the 1970s to mars and to the outer planets. we're now in another golden age of planetary exploration, particularly on mars with curiosity rover so actively exploring there. so we're right in the present moment here when we're with the mars rovers. and i wonder what we might see here in 10 years or 20 years as planetary exploration continues, with great success, we hope. and there is much talk about having a human mission to mars by about 2030 or so.

if that should happen, that will probably be the stellar attraction in the museum by the time the next major anniversary rolls around. you can watch this or other american artifacts programs at any time by visiting our website. cspan.org/history. we're back live now at the smithsonian national air and space museum where the museum today is celebrating its 40th birthday. it was 40 years ago today that president gerald ford dedicated this museum. in about a half hour, we'll bring you live coverage of the events celebrating that anniversary. in the meantime, we want to hear from you. our phone lines are open. 202-748-8900 for those in the eastern or central time zones. if you live out west,