topic 8 people in space - penny...

420 MHR • Space Exploration

People in SpaceThere are many reasons why all types of technology are developed.In Unit 5, you’ve seen that some technology is developed out ofcuriosity. Galileo built his telescope because he was curious aboutthe stars and planets. You’ve also learned that some technologiesare built to help countries fight an enemy in war. The German V-2rocket is one example of this. You may have learned in social stud-ies class about the cold war between the United States and the for-mer Soviet Union. There was no fighting with guns or bombs.However, these countries deeply mistrusted each other and becamevery competitive. They tried to outdo and intimidate each other.This competition thrust these countries into a space race, whichwas a race to be the first to put satellites and humans into space.Topic 8 looks at how the desire to go into space drove people toproduce technologies that could make space travel a reality.

Breaking Free of Earth’s GravityAlthough space is only a hundred or so kilometres “up there,” it takes ahuge amount of energy to go up and stay up there. The problem isgravity. Imagine throwing a ball as high as you can. Now imagine howhard it would be to throw the ball twice as high or to throw a ball twiceas heavy. Gravity always pulls the ball back to Earth.

Anything that escapes Earth’s gravity completely must reach a speed ofabout 8 km/s (29 000 km/h)! The rocket power needed to put capsules intoorbit with people inside is incredible. If thesmallest thing goes wrong, the rocket mayexplode or crash land. Once in orbit, a bro-ken windshield, a misfiring control rocket, ora malfunctioning heat shield spells disaster.

Sputnik 1 and Vostok 1The Soviet Union was the first to success-fully orbit a satellite with no astronautsinside. They launched Sputnik 1 in 1957.The Soviets were also first to put a personin space. On April 12, 1961, CosmonautYuri Gagarin, in his Soyuz class space cap-sule, Vostok 1, orbited Earth once at analtitude of 302 km for 108 min.

Figure 5.58 Sputnik 1 wasthe world’s first artificialsatellite. It was only aboutthe size of a basketball andweighed 83 kg. It tookabout 98 min to orbit Earth.This was a greatachievement and markedthe beginning of the spaceage for humankind. Figure 5.59 Vostok 1 travelled at

close to 29 000 km/h. The rocket thatcarried cosmonaut Yuri Gagarin tospace was Vostok 8K72K. Gagarinwas the first person actually to see that Earth is round! After re-entering the atmosphere, his capsuleparachuted to the ground. (He ejectedfrom his capsule before it landed andparachuted to the ground separately.)

T O P I C 8

On June 16, 1963 Valentina Tereshkova, a 26-year-old Soviet cosmonaut, became thefirst woman to travel in space. She was launched into orbit aboard the Soviet space-craft, Vostok 6. She orbited Earth 48 times and spent almost three days in space. Shenever made a second trip into space.

Figure 5.57 Space shuttle Atlantisblasts off in 1997 on its way to dockwith the Soviet space station Mir.

Alan Shepard and Freedom 7The American response to the Soviet manned space program wasProject Mercury. The ultimate goal of Project Mercury was to placean astronaut in orbit. On May 5, 1961, aboard the spacecraftFreedom 7, Alan B. Shepard, Jr., became the first American astronautin space. Shepard flew a suborbital flight. A suborbital trajectory isone in which the spacecraft is boosted above the atmosphere andthen falls back to Earth without going into orbit. In 1962, astronautJohn Glenn was the first American to make a full orbital flight.

The Apollo ProgramUnited States scientists were determined to play an important role inspace exploration. Now that they had safely put a person in orbit, theyset their sights on the Moon. The Apollo Program was designed tosend a three-person team to the Moon, land two of them, and bringeveryone back safely. The Apollo spacecraft consisted of an orbiter (thecommand and service modules), and a lander (the lunar module).

The Moon LandingIn the summer of 1969, Apollo 11 carried the first humans to the surfaceof another world — the Moon! Neil Armstrong was the first to steponto the Moon’s surface, followed by Edwin Aldrin. Michael Collinsmanned the command module in lunar orbit. As Neil Armstrongstepped onto the lunar surface, he said these famous words: “That’s onesmall step for [a] man, one giant leap for mankind.”

People in Space • MHR 421

Figure 5.60 Alan Shepardwas the first American inspace.

Project Gemini was abridge from ProjectMercury to the ApolloProgram, the programthat landed astronauts onthe Moon. Project Geminiput teams of two astro-nauts in orbit. The Geminiastronauts practiseddocking manoeuvres,performed space walks,and spent longer periodsof time in space to pre-pare for the lunar landing.

Consider the words thatNeil Armstrong spokewhen he stepped onto theMoon’s surface. In yourScience Log, write downwhat you think he meantby them. What would yousay if you were the firstperson to step onto thesurface of Mars?

Apollo astronauts leftreflectors on the Moonso that astronomerscould bounce laserpulses off them. Bytiming how long thelight takes to return toEarth, they are able tomeasure the distanceto the Moon to within afew centimetres.

Figure 5.61 Edwin Aldrin works on some equipment near thelunar module. Neil Armstrong took the picture.

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Design a Space Capsule Space capsules have to withstand the tremendousacceleration of a rocket launch. They have to pro-tect the occupant from the vacuum of space andthe radiation from the Sun while in orbit. Finally,they have to withstand the heat of re-entry andland safely.

ChallengeDesign and construct a “capsule” that can belaunched and will land safely with its “astronaut,”a raw egg, intact. It must also be able to withstandthe “heat of re-entry” in a pot of boiling water.

Safety Precaution

• Any completely airtight container will build uppressure inside when heated. To avoid any dangerof an explosion, your capsule must be able to “breathe.”

• Do not boil your capsule for longer than 3 min or it may explode.

Apparatushotplatepottimergloves that serve as hot padstongs

Materialseggsany kind of padding or outside container is allowed aslong as your teacher doesn’t find it to be dangerous

Design SpecificationsA. All the capsules will be launched by the same

device provided by your teacher.

B. Your capsule must fit into the launching device.

C. You may use a parachute if you want to.

D. After a successful flight, your capsule will beplaced into a pot of boiling water and cookedfor 3 min. Your egg will then be opened to seeif it is still raw. A successful flight means thatyour egg is unbroken or uncracked afterward.

Plan and ConstructWith your group, discuss any egg drop-typeevents you have done or seen. What kind ofpadding can keep an egg safe?

Is it important to prevent your capsule fromtumbling in flight?

Discuss whether or not a parachute is needed.

How will you keep your egg from cooking?


S K I L L C H E C K

Initiating and Planning

Performing and Recording

Analyzing and Interpreting

Communication and Teamwork

Evaluate1. Which is harder on the eggs — launching

or landing?

2. Were there any parachute designs thatfailed to open properly? Why did they fail?

3. What characteristics did the most success-ful “heat shields” share?

Extend Your Skills4. The Americans parachuted their astronauts

into the ocean while the Soviets landed onsolid ground. How much of a differencedoes that make in designing to ensure asoft landing?

5. Can you think of any devices we use onEarth that use the same principles as the capsules?

Meeting in SpaceCold war tensions between the Soviets and Americans were easing inthe 1970s. The Americans proposed a joint mission of the two coun-tries. They would use existing hardware, Apollo and Soyuz, in a linkingmission. The Apollo/Soyuz test project was flown in 1975. It was thefirst international space mission. Apollo/Soyuz was a test of the warmerrelations between the United States and the Soviet Union and wouldhopefully be a preparation for a future international effort in building apermanent space station. A universal docking module was designed toenable the linking of the two spacecraft to take place. Each countrybuilt its half of the docking linkage. Joint tests were done to ensureworkability and reliability of the linking parts.

Life-Support CompatibilityThe Soyuz and Apollo spacecraft provided life support to their crews indifferent ways. This posed a problem for the linking structure. Manyfacets of the life-support systems had to be made compatible. Theatmosphere on Earth is a mixture of 78 percent nitrogen and 21 per-cent oxygen, with small quantities of water vapour and carbon dioxide,plus traces of other gases. Since astronauts (like all people) continuallybreathe oxygen and generate carbon dioxide and water vapour, thespacecraft needed devices to replenish oxygen and to eliminate excesscarbon dioxide. The Soviet and American engineers removed carbondioxide and humidity by using the same chemical reactions. However,they approached the problem of oxygen supply differently.

Table 5.1 Soviet/American Oxygen Production in Space (as of 1975)

The module between the American and Soviet craft was designed toact like a life raft. The module’s atmosphere could be set to be the sameas existed in either the American or Soviet crafts. This made it easierfor the astronauts and cosmonauts to move between the two vessels.

Many other detailed considerations (other than life support) wereslowly worked out. Five years after the original proposal was offered,the mission flew successfully.


From the beginning, sci-entists had cosmonautsand astronauts do stren-uous exercises while theyworked in space forextended periods of time.Even with this exerciseprogram, their muscleswere so weak uponreturn to Earth that theyhad to be lifted from theircapsules and placed inwheelchairs. Why did thishappen? On Earth, weare constantly workingagainst gravity. Liftingyour arm to take a drinkinvolves lifting a weight— your arm — which islevered for speed and notforce. In space, all bodymovements are done inmicrogravity, whichmeans your musclesexert very little force.Therefore, the musclesatrophy or deteriorate.

Soviet system American systemCabin atmosphere 80% nitrogen, 20% oxygen at 100% oxygen at about one-third

normal air pressure air pressure

Advantages simplicity and minimal danger a switch from cabin to suit systemfrom fire oxygen would not subject the crew

to decompression problems

Disadvantages cosmonauts would be exposed to danger from fire, requirement forpotential decompression should they flameproofing all materials used inhave to switch to a spacesuit life- the cabinsupport system in an emergency

Oxygen chemical reactions with solid oxygen stored in high-pressurereplenishment chemicals containers

The Space ShuttleAs the 1970s drew to a close, the UnitedStates decided to develop a reusable space-craft — the Space Shuttle. Up to this time,all spacecraft could be used only once. Areusable spacecraft would lower the cost ofworking in the near-space environment of aspace station. At 56 m long and with a massof 100 t, the shuttle became NASA’s primarylaunch vehicle. It is used as a lab to doexperiments in space, to deploy satellites, tophotograph Earth, and to carry repaircrews for orbiting equipment.

Columbia’s First FlightThe first shuttle, Columbia, flew its first mission to space in 1981. Someof the heat-shielding tiles were damaged during the launch, but thetiles on the underside were intact. These tiles protect the shuttle fromburning up in the atmosphere upon re-entry. The shuttle is shaped likea plane because it glides to Earth with no power of its own.

Seven months later, Columbia flew again. The Canadian-built space arm(the Canadarm) was tested on this flight and has been part of all shuttlessince. This second mission proved that a craft like the shuttle could beused over and over.

Canadian Astronauts Join InIn 1983, the Canadian Space Agency hiredCanada’s first team of six astronauts: RobertaBondar, Marc Garneau, Steve MacLean, KenMoney, Robert Thirsk, and Bjarni Tryggvason.In 1992, Chris Hadfield, Julie Payette, MikeMacKay, and David Williams joined the teamof Canadian astronauts. Roberta Bondar andKen Money left the CSA in the summer of1992 and Capt. Mike McKay in 1995.Canadian astronauts spend most of their timetraining with the Americans at NASA.

Marc Garneau became the first Canadian inspace aboard Challenger (STS-41G) in 1984.Roberta Bondar became the second Canadian,and the first Canadian woman, in space aboardDiscovery (STS-42) in 1992. Both were missionspecialists conducting research. Canadian astro-nauts will remain mission specialists and payloadspecialists for a long time because Americansuse their own astronauts to pilot the shuttles.


Figure 5.62 When the shuttle lands in California, it is returned toFlorida on the back of a Boeing 747. The shuttle is almost as big asthe commuter jets that fly from Edmonton to Calgary.

All shuttle missions aredesignated numbers thatbegin with “STS.” Thisstands for space trans-port system.

Figure 5.63 Canadianastronaut Chris Hadfield“floats” through the dockingmechanism, as crews from theAtlantis and Mir-20 spacecraftgot together during spaceorbit in 1995. On his secondtrip into space in 2001, Chrisbecame the first Canadian to“walk” in space.

Space travel is always adangerous endeavour. In1986, the shuttleChallenger was to launcha mission that included ateacher who would teacha lesson in space. A leakin one of the solid fuelboosters ignited the mainfuel tank, which explod-ed, destroying the shuttleand killing everyoneaboard.

The International Space StationIn addition to launching and fixing satellites, the shuttles are beingused to help build the International Space Station (ISS). This project istruly international as it involves contributions from 16 nations. It is thelargest and most complex international scientific project ever undertak-en. It will contain six state-of-the-art laboratories for internationalresearch. Along with the United States (NASA), major partners in theISS are Canada (CSA), the European Space Agency (ESA), Japan(NASDA), and Russia (RSA).

The Next Canada ArmCanada developed a second generation of space robotics forthe ISS that will be a key component for the station’s assem-bly and maintenance. The device, called the Canadian spacestation remote manipulator system (SSRMS) or“Canadarm2,” is a giant mechanical arm attached to thespace station. In 2001, Canadian astronaut Chris Hadfieldtravelled into space to help attach the Canadarm2 to the ISS.Attached to the end of the arm is the special purpose dexter-ous manipulator (SPDM) or “Canada Hand.”

Benefits from the ISSThe International Space Station will provide an orbital labora-tory for long-term research, where one of the fundamentalforces of nature — gravity — is effectively reduced by the free-fallingeffect. In addition, research in biology, chemistry, physics, ecology, andmedicine can be conducted. In short, the science will cover all the sci-ences we do on Earth, but in the microgravity environment. The term“microgravity” is used instead of “zero gravity” because there is almostas much gravity in orbit as there is on Earth.


China has been workingon a manned space pro-gram of its own for thelast several years. TheChinese are somewhatsecretive about this pro-gram, but news reportssay that they are close totheir first launch. Watchthe newspapers in thecoming months and yearsfor new developments.

Figure 5.64A and B This is the stateof the International Space Station inthe year 2000 when its first crewwent aboard. Three pieces had beenconnected at this time. The first crewto occupy the station is shown in theinset. From the left, they are RussianCosmonaut Yuri Gidzenko, U.S.Astronaut Bill Shepherd, andCosmonaut Sergei Krikalev.

Figure 5.65 Canadiancompanies have produceda large version of the spacearm that will attach to thespace station. It has a“hand” unit on its end.

Turn to the Unit 5Project, An Arm of

Your Own, on page 432of your textbook. The projectgives you a chance to designyour own manipulating arm.

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Weightlessness occurs because orbiting has the same effect as falling. Inorbit you are constantly falling around the world!

The medical benefits of conducting science in space could lead tonew drugs and a new understanding of the building blocks of life whenwe see how they behave in microgravity. Researchers also expect athorough understanding of the effects of long-term exposure onhumans in a microgravity environment.

Industrial benefits may lead to stronger, lighter metals and morepowerful computer chips.

While some experiments will take place inside the space station, otherswill take place externally. These experiments will help reveal the effectsof long-term exposure to the external space environment. Understandingphenomena, such as extreme temperatures and micro-meteorites, willhelp engineers improve spacecraft design. Observations of Earth willenable researchers to study changes to our environment whether they

occur naturally or by human action. Other benefits mayalso lead to advanced weather forecasting sys-

tems and the most accurate atomic clocks.Commercialization of space researchwill enable industries to explore new

products and services. Finally, theresult of such innovation will createnew jobs here on Earth and in space.


The European SpaceAgency has a core ofastronauts too. TheEuropean astronauts’home base, the EuropeanAstronaut Centre, islocated in Cologne,Germany. For theInternational SpaceStation, internationalcrews will come toCologne to be trained inoperation of the ESA con-tribution to ISS: theColumbus Laboratory,the automated transfervehicle, and a number ofpayload facilities for sci-entific experiments.

Figure 5.66 This is how the International Space Station will look when it is finished.

www.mcgrawhill.ca/links/sciencefocus9

There were many space stations before the International SpaceStation. In the early 1970s the Soviets began orbiting a series of

space stations called Salyut. Later, in 1986, they launched Mir, whichstayed in orbit until 2001. The Americans launched Skylab in 1973.Research one of these older space stations to find out some of their

scientific accomplishments. Write a report of your findings.Go to the web site above, and click on Web Links to

find out where to go next.

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A Debate: Merits of Space Travel Using AstronautsThink About itDreams of human exploration of the solar sys-tem have never died, however expensive it maybe. By the end of the twentieth century, propos-als by NASA and independent teams for a voy-age to Mars had again caught people’s interest.Still, the least expensive of the proposals had aprice tag of over $30 billion Canadian.

Do you think we should send people to explorethe Moon and planets in our solar system? Whatare the advantages of space travel using astronauts?What are the disadvantages? Are there betteralternatives? In this investigation, you have theopportunity to debate them.

How Can Science Help?Scientists must monitor astronauts' reactions togravity and overall health in preflight tests andwhile they are in space. Research must be carriedout into developing better technology for spaceflights and into the possibility of living and workingin space permanently.

Resolution“Be it resolved that a modern aerospace program,to be effective, must involve sending people toexplore outer space.”

ProcedureRead the “Points For” and “Points Against” onthis page and think about other points that couldbe made in favour of and against this resolution.Two teams made up of two students each willdebate the topic. One team will speak in sup-port of the resolution and the other one willspeak against it.Two other students will be assigned to workwith each team to research background infor-mation needed to make a strong case for thepoint that the team is defending.

The rest of the class will act as the jury inhearing the debate. In preparation for thedebate, they should do their own research inorder to understand the science and technologybehind the issues raised.Your teacher will provide you with the properdebating procedures to follow.

Points For• Space travel using astronauts puts humans “on site”

to experience the mission first hand; unmannedspace travel is limited by what information computerscan relay to Earth.

• Space travel using astronauts is the only realistic wayto study the effects of space travel on the humanbody and other living organisms.

Points Against• Space travel using humans is much more costly than

space travel using robots, and diverts money awayfrom other, perhaps more beneficial, projects.

• Space travel using astronauts puts the lives ofhumans at risk; space travel using robots does not.


S K I L L C H E C K

Initiating and Planning

Performing and Recording

Analyzing and Interpreting

Communication and Teamwork

Analyze1. (a) Based on overall presentation, which

team won the debate?(b) Was it the team’s research or its deliv-

ery that made their case more convinc-ing? Explain.

2. What was your position on the issue ofastronaut versus robotic space travel beforethe debate? Did the arguments you heardfrom the two teams change your mind? Ifso, explain how. If not, did the team repre-senting the view opposite yours still raisesome good points you hadn’t thought ofbefore? What were they?

For tips on decision-making, turn to Skill Focus 8.

1. Name two things that engineers need to consider when designing a spacecapsule to protect the astronaut.

2. Why is the space shuttle different from all the other space vehicles thatcame before it?

3. What is the main role that Canadian astronauts have on the shuttle missions?

4. Explain the term “microgravity.”

5. Thinking Critically Think of your everyday activities. What is one thingyou do that would be difficult to do in a microgravity environment?Suggest a method for helping astronauts overcome this difficulty if youwere designing a spacecraft.

6. Apply What experiment would you suggest be tried on the ISS? Describewhy you think the space station is the right environment to perform yourexperiment.

7. Thinking Critically Describe two reasons why new technology is developed. Provide specific examples from Unit 5 with your answer.


T O P I C 8 Review

SPAR Aerospace, the Canadian company that designed andbuilt the Canadarm, is also the maker of its successor, theSSRMS (the Space Station Remote Manipulator System or“Canadarm 2”) and the other components that make up theInternational Space Station’s Mobile Servicing System. Thisnewer arm is so advanced that, once astronauts on the

delivery shuttle released its travel restraints, it walked out ofthe cargo bay on its own.

Suppose that a similar Canadian company posted the fol-lowing internship notice on the Internet. Write your applica-tion. Then exchange it with that of a friend. Discuss thepossible strengths and weaknesses of your applications.

If you need to check an item, Topic numbers are provided in brackets below.

Key Terms

Reviewing Key Terms1. In your notebook, match the description in

column A with the correct term in column B.

A B

• planets with gaseous • suborbital (8)composition

• an orbit a few hundred • microgravity (8)kilometres above the ground

• has taken the place of • inner planets (7)photographic plates for telescopes

• an orbit that takes 24 hr to • low Earth orbit (6)circle Earth

• the nearly weightless • geosynchronous orbit (6)conditions in orbit

• stream of charged particles • rocket (6)coming from the Sun

• fleet of satellites used to • gravitational assist (6)locate things on Earth

• a space flight that • CCD (6)goes only part way around Earth

• planets with terrestrial • global positioning composition system (6)

• a device that uses controlled • outer planets (7)burn of a fuel to propelitself directly upward

• a method of acceleration • solar wind (7)that uses gravity

Understanding Key Concepts2. Where would you expect the solar wind to be

the most intense and the least intense? Why? (7)

3. Venus is farther from the Sun than Mercury,yet it is hotter than Mercury. Why? (7)

4. What changes in payload have rockets hadfrom World War II to the space age? (6)

5. Name three things that computers are usedfor by space engineers. (6)

6. Why are most of Canada’s astronauts researchscientists? (8)

7. Scientific research will be done on theInternational Space Station. Name two newthings that might be developed on the spacestation. Pick one in biology and one in engi-neering. (8)

8. Apply Name two existing uses for the globalpositioning system. Think of one new appli-cation for this system. (6)

Wrap-up Topics 6–8 • MHR 429

T O P I C S 6 – 8Wrap-up

rocketpayloadexhaust velocitystaged rocketballistic missilecosmonaut

gravitational assistcharge coupled device (CCD)artificial satellitelow Earth orbitgeosynchronous orbitremote sensing

global positioning systemsolar windinner planetsouter planetssuborbitalmicrogravity

Q Were you nervous on your first mission?

A I was, but not for the reasons you’d think. Iwas more nervous about possibly making amistake. A typical shuttle flight costs about$400 million U.S., and often on orbit we haveonly one chance to perform a task correctly. Ithink I was more worried about messing upthan about the small chance of injury ordeath.

Q What did you find most memorable about your spaceflight?

A I was in a state of exhilaration throughout myspace flight. It didn’t matter whether I wasperforming experiments or looking out thewindow at the beautiful Earth below or brush-ing my teeth. I was exhilarated the whole timeI was in space.

Q What are you most proud of during the mission?

A I am most proud of the fact that I worked suc-cessfully as a team member, not only with mycrew mates aboard the shuttle but also withthe flight controllers and scientists on theground, to accomplish 100 percent of what wehad intended to do.

Q What is the greatest challenge to being weightless?

A Stabilizing my body in a weightless environ-ment so I could perform an intricate task waschallenging. On Earth, gravity helps to keepour feet firmly planted on the ground, and wecan easily remain stable and oriented. Inspace, we may start an experiment in front ofa laboratory rack, but within seconds we’llbegin to drift off unless we are properlyrestrained.

Q I understand you helped design an antigravity suit.How does it work?

A An antigravity suit (or g-suit) is a device thatallows an astronaut’s cardiovascular system(i.e., heart and blood vessels) to readapt togravitational forces during the return toEarth. A g-suit looks like a pair of trousers,but within the leggings and lower abdomen ofthe suit are rubber bladders that can be inflat-ed. When inflated, the bladders collapse theblood vessels within the legs and abdomen,and shift that blood volume up to the chestand head where it’s most needed during re-entry.


ExpertAsk an

U N I TU N I T

Ever since Robert Thirsk — who grew up in British Columbia,

Alberta, and Manitoba — was in Grade 3, he knew he wanted

to be an astronaut. He devoted the rest of his education to

becoming an astronaut — he earned four university degrees,

including a Bachelor of Science from the University of

Calgary. After training since 1984, Robert finally got his wish.

In 1996, he spent 17 days aboard a space shuttle.

Ask an Expert Unit 5 • MHR 431

Q Does everyone wear these suits?

A All astronauts will wear antigravity suits dur-ing re-entry. It’s up to us whether we inflatethe bladders or not. For instance, if we feellight-headed or notice visual problems, thenwe’ll inflate the suit. We’ll keep the suit inflat-ed after touchdown until a medical doctor hasdetermined that it is safe to deflate it.

Q I understand you conducted experiments on materialsprocessing as well as medicine. Could you tell meabout one of the experiments you conducted in space?

A Medical scientists are concerned that very longspace flights — such as missions to Mars —will cause astronauts’ bones to demineralizeand muscles to atrophy. They are also con-cerned that we may be exposed to high levelsof ionizing radiation. On my flight, we investi-gated these potential medical problems. Inparticular, we spent a lot of time investigatingchanges in our muscle strength and perfor-mance as well as the reasons for these changes.

Q How did you test this?

A The main device we used for these muscleexperiments was the torque velocitydynamometer, or TVD. You can think of theTVD as an arm- or leg-wrestling machine.Every couple of days we’d strap ourselvesinto the TVD and have a series of wrestlingmatches with the machine. Sometimes theastronauts would win these matches, some-times the machine would win. What wasmost important, however, was that the TVDmeasured subtle changes in our musclestrength and speed of contraction.Throughout the mission, we sent this scien-tific data down to the scientists on theground. By studying the data, scientists could better understand the changes thatwere taking place during space flight at thelevel of our individual muscle fibres.

Q Are you planning to go back to space?

A Yes. At present, I am undergoing advancedastronaut training not only on space shuttlesystems but also on the new International SpaceStation. Several nations, including Canada, areworking together to build this marvellous newresearch platform. The space station is nowbeing assembled and we expect that by 2004 itwill be completed. It’ll be about twice the sizeof a football field and the second brightestobject in the nighttime sky. If I have anopportunity to fly another space mission, Ihope it will be aboard this station.

Not only do astronauts have to deal with the feel-ing of weightlessness, but they also have to beable to work under extra g-forces during launch.Try this activity. Crumple up a piece of paper andtoss it into a basket five times. Then hang a 2 kgweight on your wrist and try again. Finally, removethe weight and toss the paper for a third set. Didthe addition and the removal of the weight affectyour accuracy? How is this exercise similar towhat an astronaut might experience on a missionto space?

The Neutral Buoyancy Laboratory is a large pool at theJohnson Space Centre. Here, astronauts train for space walks.


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An Arm of Your Own

Canada has designed the Canadarm for the shut-tles, and a giant arm for the International SpaceStation. Gears move the “joints” of the Canadarm.The arms move as the gears turn. The Canadarmhelps launch and recover satellites. As you learnedat the beginning of Unit 5, the Canadarm helpedrepair the Hubble space telescope.

Remote manipulation technology is importanton Earth too. Many materials are too dangerousto handle directly. For example, radioactive mate-rials, toxic waste, and hot metals cannot be han-dled directly by humans.

ChallengeDesign and construct a device that can removetwo objects from the centre of a 6 m diameter cir-cle without you going into the circle.

Safety Precautions Be careful of sharp objects and tools while constructing your device.

MaterialsYou may use any materials that your teacherdeems safe. Look around your house or garage forold pipes, wood, long-handled tools, and evencurtain rods might come in handy.

Design SpecificationsA. The two objects will be placed at the centre

of the circle, either on the floor or on a table.(Your teacher will tell you which.)

B. You will know in advance what the twoobjects are. One will be heavier and largerthan the other.

C. At your turn, you and your group may posi-tion yourselves anywhere outside one third ofthe circle to operate your device. At no timemay anyone in the group step into the circle.

D. You may change the grasping end of yourdevice after retrieving one of the objects.

E. A successful retrieval occurs if an object isremoved from the circle without the devicetouching the floor, and is set down outsidethe circle undamaged.

F. You have 5 min to remove the objects fromthe time your teacher calls on your group.

Unit 5 Project • MHR 433

Plan and Construct1. This is a big project. You and your group will

need to brainstorm ideas well in advance ofthe day of the event. A good rule of thumb isthat you want to be able to lift the objects oneweek before the event. This gives you a weekto fine-tune your arm.

2. There are many ways to do this. Brainstormfor lots of ideas. Sometimes a crazy idea willtrigger an excellent one.

3. Your arm will need to reach the centre of thecircle and grasp the objects. Keep both ofthese things in mind.

Evaluate1. Most designs start out complicated, and a

simplifying idea comes from hard work. Wasthere a point in your design where a simplify-ing idea emerged? Explain the process youwent through to come up with your finaldesign.

2. How many completely different ways didyour class solve this problem? How are yourclassmates’ designs like the one your groupdesigned? How are they different?

3. What would you change about your design ifyou were to begin again?

4. Think of three places on Earth where adesign like yours would be useful to people inreal-life situations.

5. What modifications would you have to makeif you were asked to make a prototype for oneof these applications?

Research one specific application of a remote manipulator on Earth (for handlingtoxic waste, for example). Design (or re-design your existing manipulator) to suitthe specific needs of this application. For example, will you need to reduce thechances of the item being dropped? How can you re-design your manipulator toincrease its hold reliability? Will you have to shield your device from its environ-ment? What other considerations will you have to take into account? You do notneed to build your new design, just create technical drawings of your new plans.

For tips on problem-solving, turn to Skill Focus 7. For help with technologicaldrawing, turn to Skill Focus 11.

Unit at a Glance• Ancient astronomers learned a lot about the

heavens without much, if any, technology.• Earth was the first frame of reference people

used.• Careful measurements of planetary motions led

to two conflicting theories of the universe —geocentric and heliocentric.

• The invention of the telescope enabledastronomers to make more precise measure-ments of celestial objects, and the heliocentrictheory won out.

• The invention of the spectroscope enabledastronomers to infer the composition of stars.

• Spectroscopy also enables astronomers to findout the direction of motion of celestial bodiesbecause of the Doppler effect.

• The distances to the nearest stars are found withparallax.

• Radio signals come from the sky. Radioastronomers made many more discoveries aboutcelestial bodies.

• Telescopes of all types have been made biggerover the years. They have been connectedthrough the use of computers. Some telescopeshave been placed in space.

• Rockets were designed for war and have beenturned to peaceful applications. All of the thingswe put in space need rockets to get them there.

• Computers are important for space technology.They are used to calculate orbits, store andmanipulate images, and to receive and act uponinstructions from Earth.

• The Hubble space telescope is one of a series ofspace-based observatories planned or launched.

• Scientists are studying Earth from space withsatellites. These satellites may be in low Earthorbits, or in geosynchronous orbits. This iscalled remote sensing.

• The global positioning system is a fleet of satel-lites used by people to locate their position onEarth.

• The Sun, Moon, and every planet (except Pluto)have been visited by at least one Earth spacecraft. We have some close-up data on these as a result.

• The main focus of a human presence in space atthis time is to occupy a space station. Canada isa partner in this endeavour, supplying manytechnological devices and astronauts as missionspecialists.


U N I TU N I T

5 Review5 Review

Understanding Key Concepts1. How did the ancient astronomers know the

planets were different than the stars?

2. How did the ancient astronomers account forday and night? How did Copernicus accountfor this?

3. Why did the ancient astronomers think thatEarth wasn’t moving?

4. Galileo observed four small stars that werealways near Jupiter. Why did he conclude thatthey were moons of this planet?

5. According to Newton, how does the Sun keepthe planets going in orbit around it?

6. How can astronomers know that two stars areof the same type?

7. Look at the spectra of these stars. What canyou say about the motions of the stars fromthese spectra?

8. Name one way astronomers have minimized,or eliminated, the twinkling of stars whenviewing through telescopes.

9. What is a radio object?

10. Give one advantage and one disadvantage ofradio waves over visible light waves for astro-nomical work.

11. What is the difference between a low Earthorbit and a geosynchronous one?

12. Give three uses for remote-sensing satellites.

13. How do computers help astronomers to getbetter images of celestial objects? Give twoexamples.

14. How were radio waves important in the studyof Venus?

15. What is the main difference between the firstfour planets from the Sun, and the next four?

16. Who was: the first human in space?_____________

the first man on the Moon? _____________

the first Canadian in space? _____________

the first Canadian woman in space?_____________

17. Canadian engineers built a lot of devices forspace missions. What is the most famous one?

18. When you pass a beam of white light througha prism, what colours are found in the result-ing spectrum?

19. What is a diffraction grating? Why are diffrac-tion gratings more useful than prisms?

20. Describe how the Doppler effect is used tomeasure the speed and direction of stars?

Unit 5 Review • MHR 435

laboratoryspectrum

star A

star B

Developing Skills21. For each star shown, give its altitude and

azimuth.

22. Answer questions (a) and (b) using the follow-ing spectra.

(a) What elements are present in each star?(b) Which star(s) are approaching us? How do

you know?

23. What value should the students in the diagramcalculate for the distance to the tree?

24. A group of students want to set up an experi-ment to show other students in their class howto find the distance to a distant building usingtriangulation. They want the measured anglesto be 88º at each end of the baseline. If thebuilding is 1.50 km away, then how long a base-line should they use for their demonstration?


W

60°

40°

30°

45°

E

S

N

XY

10.6 m

63°76°

hydrogen

sodium

mercury

A

B

C

D

Critical Thinking25. Suggest a reason why Canada was the first

country to place a geosynchronous communi-cations satellite into orbit.

26. Give an example of a technology designed forwar being used for a peaceful space sciencepurpose. Why do you think this happens?

27. Building and maintaining the InternationalSpace Station and a possible manned mission toMars will be incredibly expensive. Suggestsome arguments for and against doing theseprojects.

28. It is said that the engineering involved insending a mission to Mars with people onboard is easy, but it is the biology that is hard.What do you think this statement means?

29. Explain why using Earth as your frame of ref-erence is the most “natural,” or common senseway to view the stars.

Unit 5 Review • MHR 437

In your Science Log, compare the Hollywood image ofhuman space travel with the reality. What is it about theHollywood image that is so appealing? Does this say any-thing about why we have spent so much time, effort, andmoney on the quest to put humans in space?

Go back to the beginning of the unit on page 354 and checkyour original answers to the Focussing questions. How hasyour thinking changed? How would you answer these ques-tions now that you have investigated the topics in this unit?

topic 8 people in space - penny...

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