this side faces the earth and doesn't the moon go around the earth? well, watch how the moon goes around the earth. what am i doing to the eraser, gang, as it goes around the earth? i'm twisting it because it turns out the eraser's going like this as it turns. and when it makes one turn like this, it'll also make one rotation. so it'll go... and--stopped it, it would just keep... stop it for a minute... ain't that neat? so the moon is turning around and around and around. and you know what? there's a reason why one side always faces us and it has to do with center of gravity and torque. did you pick that up on the chapter on rotational motion? did you pick that up? and when you picked that up, did you say to your mother and father, hey, you know what i just i found out? there's a reason why one side of the moon faces us all the time. how many people did share that with their parents? how many say, well, my parents don't give me anything, i'm not gonna give them anything? do you people share these ideas with the people at home? how many of you people d

now is the earth really moving towards the moon? we on earth think, no, no, no, no. the moon is moving toward the earth. there's a force on the earth, i mean, there's a gravitational force between the earth and the moon that pulls the moon this way, right? why don't the moon crash? because it's moving like that. so as it's being pulled instead of coming over here, it's moving like this. it doesn't get to here, it gets to here. it's being pulled like that, instead of getting here, it gets to here. and so it gets pulled around and around and around in a circle, but guess what the direction of the acceleration is as it's going around and around and around the circle? it's toward the center of the earth, see? so we think of the moon as going around and around and around us like i take a rock in the end of a string and i go whirl it around, around, around. we talked about the idea that the force along the string is acting toward me, right? the rock is really accelerating toward me. if it weren't it would go somewhere else, but it keeps pointing toward me all that time, hu

let it fall to earth by earth's gravity. get the sun out of the way, okay? just by earth's gravity. splat. i'll bet you're sitting next to someone who knows what the speed of the splat is, at least the upper speed, check it out. what's the maximum falling speed for planet earth? what's the answer, gang? 11.2 kilometers. 11.2 kilometers per second, right on. it's gonna be the same speed it takes to escape. how fast it has to go to get out there will be how fast it would fall back in again 'cause what slows it down-- hey, hey, hey, and it all ties together. are you ready for quiz that'll take care of all of mechanics? a little sample quiz, here we go. look over here, folks. here's a satellite going around in elliptical orbit around the earth. i'm gonna ask you a bunch of questions and see if you can answer the questions. at what point a, b, c, d is the gravitational force that acts on that satellite a maximum? here, here, here or here? write on your paper a 'a,' a 'b,' a 'c,' or a 'd'. or if you think the gravitational force on the satellite is the same everywhere, then you write down

he follows the path of earth below. beyond human sight, friendship 7 make as slow boat out of the sun as the spacecraft girdles the earth every 90 minutes, like a shooting star at five mile as second, 17,500 miles an hour, john glenn streaks away from today into the night of tomorrow racing towards the dawn of yesterday. as glenn sights the sights of perth and flashes over australia and across the pacific to contact waiting ground stations in wymas, mexico and california waits as friendship 7 streaks home to the land of its origin. an unseen comet lining across the united states in eight lightning minutes of flight. completing three history-making circuits of the globe, john glenn fires retro rockets so to slow the spacecraft. to direct it back to earth. >> five, four, three, two, one. >> roger. retros are firing. are they ever. it feels like i'm going back toward hawaii. >> then the first ominous note. the first warning of possible disaster. a chilling signal flashes an indication that the capsule's heat shield may be

object about 6 miles in diameter actually struck the earth, threw up dust and debris into the earth's atmosphere, shut down much of the sunlight, which, of course, killed the plants and the animals that lived on the plants, so the dinosaurs checked out about 65 million years ago as a result of a near-earth-object impact. >> another n crater in arizona about 50,000 years ago, and the big ones are still coming down. in 2008, there was a strange explosion above the african desert. scientists say it was caused by a neo that almost hit the planet. >> and pieces were found on the desert floor, and so scientists are now studying those pieces -- or meteorites -- to understand what this asteroid was made of. >> the whole world needs to know when another big neo might hit, so nasa is part of an international effort to watch and plan. >> so the goal is to find them and track them and predict that they might make an earth impact, say, 10, 20, 30 years into the future, and if we have that much time, we have the technology to deal with it. for example, you could run a spacecraft into them, slow the

over. >> home to earth comes the voyager. carrier "randolph" in 4 hours and 56 minutes, john glenn has streaked through three days and three nights and over 81,000 miles. never a journey so far. never a traveler so welcomed by the world. so brief a journey in time. so far the way. so long the hours for those who wait. asglnn has waited. as all the world has waited. to salute the glenns with vice presidenton johnson. as the president of the united states arrives at cape canaveral, to be greeted with johnnd annie glenn, by the cheers of thrilled lines of proud americas. in ceremonies at mercury control center. president john f. kennedy presents the nasa distinguish service medal to astronaut john glenn. as annie and lynn and david glenn proudly share applause with the other astronauts and with the world. as john's parents learn firsthand about "friendship seven." as does marine corps commandant general david m. shupe and the president of the united states. and this rainy day in washington is a happy day. as the president and th

three februarys later, john glenn found himself circling the earth from the heavens at 13,000 miles an hour staring at the sunset that was even more spectacular than he ever imagined as the nation looked on. in new york, thousands of commuters stood still in grand central station to watch the takeoff. and even walter cronkite allowed himself a little show of national pride from the broadcaster's chair as glenn's rocket lifted from the earth, cronkite rooted for the home team saying, go, baby, go. the context of all this was important. five years earlier, the soviet union had beaten us into space with an unmanned satellite. an achievement that prompted nikita khrushchev to quip that now the u.s. slips under a soviet moon. and that's where the other three men we honor today come in. seven years after glenn circled the earth, neil armstrong, buzz aldrin and michael collins put to rest any doubts about the position of the united states in the world. the cold war was now being fought in space and these men proved that the u.s. was winning. it wasn't easy. as president eisenhower stated at t

these planets called super of earths are bigger than our own earth.. others are different. it's a family we are already discovering. >> what's the breakthrough for the experiment that allowed you to observe it here in our world that you can match them. >> a couple of them. the first breakthrough was figuring out how to find them. in that sense, the nasa mission revolutionized the field. in the last two years and the few years ahead, it's going to really discover all those planets in a way in which we can then study them. >> so the astronomy, you can observe the experimental field that is the universe to see whether they are there. >> they are light years away, but we see them and we can tell how often they occur around other stars. >> what are you using to understand where we live to know whether what you're seeing is similar to where we are? >> that's the big question. we want to know which of those planets are similar to earth and how often do you have the same environmental conditions. so you have to then use other telescopes and maybe discover mor

>> the capsule looks okay. >> home to earth comes the voyager. transported now to the aircraft carrier "randolph" in four hours and 56 minutes, john glenn has streaked through three days and three nights and over 81,000 miles. never a journey so far. never a traveler so welcomed by the world. so brief a journey in time, so far the way, so long the hours for those who wait. as annie glenn has waited. as all the world has waited. to salute the glenns with vice president lyndon johnson. as the president of the united states arrives at cape canaveral, to be greeted with john and a cheers of thrilled l of proud americans, incemonies center, president john f. kennedy presents the distinguished service medal to john glenn. as annie and david glenn proudly share applause with the other astronauts and with the world. as john's parents learn firsthand about friendship 7, as does marine corps general david m. shoop and the president of the united states. and this rainy day in washington is a happy day as the president and the astronaut arrive. to drive thro

in the process, they contributed to a better world here on earth.we owe it to them and to our nation not to abdicate our nation's role as the leader in space exploration. what they began, we are summoned to continue. thank you. [ applause ] >> ladies and gentlemen, the administrator of the national aeronautics and space administration, mr. charles bolden jr. >> mr. speaker, mr. reid, mr. mcconnell, ms. pelosi, members of congress and honored guests, as we embark upon a next chapter of human space exploration, we stand on the shoulders of the extraordinary men we recognize here today. those of us that have had the privilege to fly in space follow the trail they forged. america's leadership in space and the confidence we can go achieve great things as a people rests on the achievements of these men. when 50 years ago this year president kennedy challenged the nation to reach the moon, to take longer strides toward a great new american enterprise, these men were the human face of these words. from mercury and gemini, on through our landings on the moon

it articulates his idea that the earth is like flesh, and the archaeology and geology in the earth are like the bones, the structure of the earth. this tied in with his idea of mother earth, with the sense that we are all tied to nature and the earth. >> a half dozen bay area museums and private collectors loan the massive sculptures to the museum for its matter and spirit retrospective. but the most unusual contributions came from stephen himself. a wall of autobiographical masks and hence from the early decades of his private study. >> he had one of the most beautiful studios i have ever been in. when you walk in, your first impression is of these monumental figures that you see in the exhibition, but if you went into the back corner of his studio, there was a series of shells with these diminutive figures. he told me, these are the heart of my studio. these little, and held intimate study is that he referred to as his sketchbook. a painter might make drawings. stephen de staebler made miniature sculptures. >> during the 1970's, he was inspired by the monuments of egypt. he assembled

the earth. and i think that is a phony ideal. i don't believe that that's what we're here to do. that man is here to use the resources and use them wisely, to care for the earth, to be a steward of the earth. we're not here to serve the earth. the earth is not the objective. man is the objective. i think a lot of radical environmentalists have it upsidedown. >> schieffer: how does that translate into some sort of theology? >> it's a world view. >> schieffer: theology is not based on the bible. that suggests that he's not a christian. >> i wasn't suggesting the president's not a christian. i accept the fact that the president is a christian. i just said that when you have a world view that elevates the earth above man and says that we can't take those resources because we're going to harm the earth by things that frankly are just not scientifically proven, for example, that the whole global warming debate, this is all an attempt to, you know, to centralize power and to give more power to the gove

>> i am interested in the physical properties of the earth and how the earth will behave: subject to different load changes. when you are building a building, you are applying a load and you are wondering if the earth will be able to supply that load. we work closely together and we come up with practical engineering solutions. >> this is when someone wants to build something. also, we have a rock piece of land. we have to have a resolution. >> in the u.s., about 2/3 of the population lives in areas that are prone to landslides. about $2 billion of damage occurs annually from landslides. unfortunately, 20-25 million people die as a result of landslides o. >> much of the coastline is either a bright red or a beige print th. >> here we are at the base of telegraph hill on lombard street. this is owned by the city. behind you is a large piece of something exposed. you are looking at a large class that was xextricated in a quarry about hundred years ago. this is a secretive sandstones, shales, accumulated debris. essentially it ended up piled up here. the quarry activity was so intense a

all we could see was the sun, the earth and the moon. so phil shaffer was given the responsibility to come up with techniques to check our spacecraft attitudes for maneuvers and those kind of things using only the sun, earth and moon and to continue to refine the techniques of aligning the navigation system onboard the lunar module once we did have to shut it down. i took my team offline and tried to figure out ways to cut down the return trip time because john aaron said there's no way we're going to make five days with the power in the lunar module. we got to cut it down to at least four days. maybe 3 1/2. so i now had the team split up and moving in several different directions. i had one team working power profiles. i had another group of people that was working navigation techniques. i had a third one that was integrating all the pieces we need. my team picked up the responsibility to figure out a data to -- way to cut a day off the return trip time and we set up formal tag-in ties. we set up working areas down in the control room p

john glenn orbited the earth three times in a spacecraft named friendship 7. the entire flight was just under five hours. this is six minutes. >> five hours before he is destined to take a giant stride into history, colonel john h. glenn jr. squeezes into his space suit. this morning the weather over cape canaveral and in the pickup areas is better. and there is an air of optimism carrying his now familiar portable air conditioner. glenn prepares to go to the 11th deck as clocks point to 6:00 a.m. eastern standard time. the skies are beginning to lighten. the colonel's date with destiny comes 10 months after the russians claimed an orbital flight and less than a year after alan shepard blazed a suborbital flight for the u.s. this is the moment when the eyes of the world turn to cape canaveral. russian orbitz were in a thick fog the secrecy. the united states stands or falls on the white-hot glare of worldwide publicity. in the capsule atop the atlas missile, the colonel will be strapped to a contoured couch. once in flight the mercury will be tilted so that th

is actually living on two dollars a year with the current world's population we'd need for planet earth's to provide the raw materials for everybody to have just poverty level the us standard of living is the prospect of adding a few billion people more pretty stupid and should we be doing something to stabilize human population. well i think definitely the questions about managing population growth come into play here at the same time we really do need to examine how we're going to manage even our existing population levels as we have a ballooning middle class in especially countries like china and india because that's something that you really can't go back on this is a population that for the most part the middle class of twenty thirty has already been born and the question is how are we going to manage this how are we going to manage natural resources and how are we going to make sort of macroeconomic policy decisions which will we'll work out by the time twenty thirty rolls around because that's something that we are definitely facing down and something that is going to occur if the

lynus gets the green light to start refiring rare earth in malaysia. you think you take off all your make-up before bed. but do you really? [ female announcer ] neutrogena® makeup remover erases 99% of your most stubborn makeup with one towelette. can your makeup remover do that? [ female announcer ] neutrogena® makeup remover. >>> welcome back to "world business today." >> speaking of commodities there, you saw the price of gold gaining in today's session. but shares of the australian mining company lynas have literally soared almost 20%. and this is on the back of news that the malaysian authorities have granted this company an operating license to run a rare refining plant. it means that the company's proposal to ship rare earth elements from australia to malaysia can proceed. lynas estimates the project will account for a quarter of the world's supply of rare earth, outside of china. this has sparked protests in both countries. this is from environmental and health concerns. among them, that the remining plant could produce harmful waste. and as a

john became the first american to orbit the earth.bruary of 1962, and now he sharing his favorite memories and one title he wishes he could have won. matt friedman reports. >> amazing to me to look back 50 years and think it's been 50 years. >> it was a flight that launched john glenn as a national hero and put america on even footing with the soviet union. >> it still seems so vivid to me. >> on february 20, 1962, glenn became the first american to orbit the earth aboard friendship 7. >> we had tried to see all the things that would happen, but we didn't see all of them. >> 50 years ago, this president's day, glenn circled the earth three times in five hours. >> i'm proud of what we all did, all seven of us did on those flights. we worked very closely together. >> so many blessings and accomplishments, glenn admits there's still one brass ring he