cambridge IELTS 9 full book

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For IELTS help http://letfl.com

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Cambridge IELTS 9

Authentic examination papers

from Cambridge ESOL

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s E C T I O N 1 Quesfions 1-10

Complete the nofes below

Write NO MORE THAN THREE WORDS AND/OR A NUMBER for each answer

J O B E N Q U I R Y

Example

Work at: a resTaurant

Type of work: 1

Number of hours per week: l2 hours

Would need work permit

extra pay when you work on 5

transport home when you worl< 6

Qualities required:

7

a b i l i t y t o 8

Interview arranged for: Thursday 9 at 6 p.rn

Bring the names of two referees

Ask for: Samira 10

10

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S E C T I O N 2 Q u e s f i o n s 1 1 - 2 0

Quesfio ns 11-1 6

Write ONE WORD AND/OR A NUMBER for each answer

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A You need to reserve a place.

B lt is free to account holders

C Y o u g e t a d v i c e o n h o w to i m p r o v e y o u r h e a l t h

D l t t a k e s p l a c e i n a s p e c i a l c l i n i c

E l t i s c h e a p e r t h i s m o n t h

12

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24 How does Spiros feel about his performance in tutorials?

A not very happy

A consulted reference materials

B had extra tutorials with her lecturers

C borrowed lecture notes from other students

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A learn more vocabulary.

B read more in their own subject areas

C develop better reading strategies

14

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s E C T I O N 4 Q〃esⅡo刀s3仁犭o

Write NO MORE THAN TWO WORDS for each answer

35 f}om rnrlitary tests are linked to sorrre recent strandings

The Baharnas (2000) stranding was unusual because the w'hales

o \\ crc all 36

were not irr a 37

Mass strandings: srtuations where groLlps of ri'hales, dolphins, etc su'ir-rt onto the beach

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R E A D I N G P A S S A G E 1

You should spend about 20 minutes

Passage 1 below

on Questions 1-13, which are based on Reading

At the time, quinine was the only viablemedical treatment for malaria Tht:

drug is derived from the bark of thecinchona treet, native to South Arnerica,and by 1856 demand fbr the drug wassurpassing the available supply Thus,when Hofmann made some passingcomments about thc desirability of asynthetic substitute for quinine, it wasunsurprising that his star pupil wasmoved to take up the challengc

During his vacation in 1856, Perkinspent his timc in the laboratory on thetop flclor of his family's hcluse IIe wasattompting to manufacture quininefrom anilincl, an inexpensive and readilyavailable coal tar waste product Dospitchis best efforts, however he did not end

up with quinine Instead, he produced amysterious dark sludge l.uckily, Perkin'sscientific training and nature promptedhim to investigate the substance f'urther.Incorporating potassium dichromatc andalcohol into the anilinc at various stages

of the experimental process, he finally

p r o d u c e d a d e e p p u r p l e s o l u t i o n A n d ,proving the truth of thc lamous scientistLouis Pasteur's words'r:hanc:e l'avoursonly the prepared mind', Perkin saw thcpotential of his unexpccted find

William Henry Perkin

The man who inuented synthetic dyesWilliam Henry Perkin was born on

M a r c h 1 2 , 1 8 3 8 , i n L o n d o n , E n g l a n d

As a boy, Perkin's curiosity prompted

early interests irr the arts, sciences,

photography, and engineering tsut it was

a chance stumbling upon a run-down,

yet functional, laboratory in his late

grandfather's home that solidified the

young man's enthusiasm fbr chetmistry

As a student at the City of l.ondon School,

Perkin became immersed in the study of

chemistry FIis talent and devotion to the

subject were perceived by his teacher,

Thomas Flall, who encouraged him to

attend a series of lectures given by the

eminent scientist Michael Faraday at the

Royal Institution Those speeches fired

the young chemist's enthusiasm further,

and he later went on to attend the Royal

College of Chemistry, which he succeeded

in entering in 185.3, at the age of 15

At the time of Perkin's enrolment, the

Royal College of Chemistry was headed

by the noted German chemist August

Wilhelm I{ofmann Perkin's scientific

gifts soon caught Hofmann's attention

and, within tr,vo years, he becams'

IJofmann's youngest assistant Not long

after that, Perkin made the scientific

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Historically, textile dyes \\,ere made

from such nertural sources as plants

and animal excretions Somet of these,

such as the glandular mucus of snails,

were difficult to obtain and outrageously

expensive Indecd, the purple colour

extracted from a snail was once so costly

that in society at thet time clnly tht,' ricl-r

could afford it Furthcr, natural dyes

tended to be muddy in hue and fade

quickly It was against this backdrop that

Perkin's disr:overy was made

Perkin quickly grasped that his purple

solution could be used to colour

fabric, thus making it the world's first

synthetic dyc Realising the importance

of this breakthrough, he lost no time

in patenting it But perhaps the most

fascinating of all Perkin's reactions to his

find was his nearlv instant recognition

that the new dye had commercial

p o s s i b i l i t i e s

Perkin originally named his dye'Iirian

Purple, but it later became cclmmonly

known as mauve (from the French fbr

the plant used to makc the colour violet)

He asked advice of Scottish dye works

owner Robert Pullar, who assured him

that manufacturing the dye would be

well worth it if the colour remained

fast (i.e would not fade) and the cost

r,vas relatively low So, over the ficrce

ob.jections of his metntor Ilofmann, he

left college to give birth to the modorn

chemical industrv

With the hclp of his father and brother,Perkin sct up a factorv not far frclm

L o n d o n U t i l i s i n g t h e c h e a p a n d p l e n t i f u lcoal tar that was an almost unlimitedbyproduct of l-ondon's gas street lighting,the dyc works began producing theworld's first svnthctically dyed matrtrial

i n 1 8 5 7 ' l ' h e c o m p a n y r e c e i v e d acommercial boost from thc EmpressEugdnie of Iirance, \.r,hen shel decidedthe new colour flattered hc.r Very soon,mauvo was the necessetry shade fbr allthe fashionablet ladies in that country.Not to ber outdonc, lingland's QueenVictoria also apperared in public wearing

a mauve gown, thus making it all therage in England as well The dye r,vasbold and fast, ernd thc public clamouretdfrrr more Perkin went back to the

drawing board

Although Perkin's fame was achievedand fortune assured by his firstdiscovery, the chemist continuedhis rr-'search Among olher dyes hederveloped and introduced were aniline

r e d ( 1 8 5 9 ) a n d a n i l i n c b l a c k ( 1 8 6 3 ) a n d ,

in the latc 1860s, Perkin's green It isimportant to note that Perkin's syntheticdyc discoveries had outcomes far betyondthe mcrely decorativc.'l'he dyes alsobecamc vital to medical research inmany ways For instance, they were used

to slain previouslv invisible microbes andbactcria, allowing r()searchcrs to iderntifysuch bacilli as tubercuktsis, choletra,arnd anthrax Artificial dyes continue tcrplay a crucial rolc todav And, in whatwould have been particularly pleasing tctPerkin, their current use is in the searr:hfor a vaccine against malaria

18

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Quesfio ns 1-7

Do the following statements agree with the information given in Reading Passage 1?

ln boxes 1-7 on your answer sheef, write

TRUE if the statement agrees with the information

FALSE if the statement contradicts the information

NOT GIVEN if there is no information on this

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Test 1

Quesfio ns 8-13

Answer the questions below

Choose NO MORE THAN TWO WORDS from fhe pass age for each answer

Write your answers in boxes B-13 on your answer sheef

8 Before Perkin's discovery, with what group in society was the colour purpleassociated?

9 W h a t p o t e n t i a l d i d P e r k i n i m m e d i a t e l y u n d e r s t a n d t h a t h i s n e w d y e h a d ?

1 0 W h a t w a s th e n a m e fi n a l l y u s e d to r e f e r t o t h e fi r s t c o l o u r P e r k i n i n v e n t e d ?

1 1 W h a t w a s th e n a m e o f t h e p e r s o n P e r k i n c o n s u l t e d b e f o r e s e t t i n g u p h i s o w n d y eworks?

1 2 I n w h a t c o u n t r y d i d P e r k i n ' s n e w l y i n v e n t e d c o l o u r f i r s t b e c o m e f a s h i o n a b l e ?

13 According to the passage, which disease is now being targeted by researchers

u s i n g s y n t h e t i c d y e s ?

20

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You should spend about 20 minufes on Quesfions th26, which are based on ReadingPassage 2 on the following pages

Quesfio ns 14-17

Reading Passage 2 has five paragraphs, A-E

Choose the correct heading for paragraphs B-E from the list of headings below

Write the correct number, i-vii, in boxes 14-17 on your answer sheet

v Reasons for the search for extra-terrestrial intelligence

vi Knowledge of extra-terrestrial life forms

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Th∷ 0∷ {s0a|o∷ h fo冖 E炖p由七色r冖 est冖 iaI InteⅡ igence

The question of whether we are alone rn the

Universe has haunted humanity for centurres,

but we may now stand poised on the brink of

the answer to that questron, as we search for

radio signals from other tntelltgent civrltsatrons

This search, often known by the acronym SETI

fsearch for extra-terrestrial intelligenceJ, is a

difficult one Although groups around the world

have been searchrng intermittently for three

decades, it is only now that we have reached

the level of technology where we can make a

determined attempt to search all nearby stars

for any sign of life

A

The pnimany neason fon the search is basic curiosity - the same curiosity about the natunal

wot"ld that dr-ives all pune science We want to know whethen we ane alone in the Univense

We want to know whether life evolves naturally if given the night conditions, or- whether- ther.e

is something very special about the Earth to have fostened the variety of life forms that

we see anound us on the planet The simple detection of a radio signal will be sufficient to

answer this most basic of all questions In this sense, SETI is another cog in the machiner-y

of pure science which is continually pushing out the horizon of our knowledge However,

there ane othen neasons for being intenested in whether" life exists elsewhere For- example,

we have had civilisation on Eanth fon perhaps only a few thousand years, and the [hreats of

nuclean wan and pollution over the last few decades have told us that our survival may be

tenuous Will we last another two thousand yeans or will we wipe ounselves out? Since the

lifetime of a planet like ours is sevenal billion yeans, we can expect that, if other civilisations

do sut"vive in oun galaxy, their ages will nange fr"om zero to several billion years Thus any

other" civilisation that we hear from is likely to be far olden, on aver.age, than ounselves The

mene existence of such a civilisation will tell us that long-term survival is possible, and gives

us some cause for" optimism lt is even possible that the olden civilisation may pass on the

benefits of thein expenience in dealing with thneats to sur-vival such as nuclean war and global

pollution, and other thneats that we haven't yet discovered,

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with it In othen words, the life form we ane looking fon may well have two gneen heads

a n d s e v e n f i n g e n s , b u t i t w i l l n e v e n t h e l e s s n e s e m b l e u s i n t h a t i t s h o u l d c o m m u n i c a t e w i t h

i t s f e l l o w s , b e i n t e n e s t e d i n t h e U n i v e n s e , l i v e o n a p l a n e t o n b i t i n g a s t a r l i k e o u n S u n , a n dpenhaps most r^estrictively, have a chemistr"y, like us, based on canbon and waten

c

E v e n w h e n w e m a k e th e s e a s s u m p t i o n s , o u r u n d e r s t a n d i n g o f o t h e n li f e fo r m s i s s t i l lsevenely limited We do not even know, fon example, how many stars have planets, and we

of transmitted power-, r"adio waves in the fnequency nange l OOO to 3OOO MHz tnavel thegr"eatest distance, and so all seanches to date have concentnated on looking for r"adio waves

in this fr"equency nange So fan thene have been a numben of seanches by various gnoupsanound the wor-ld, including Austnalian seanches using the radio telescope at Pankes, NewSouth Wales Until now there have not been any detections fnom the few hundned slanswhich have been seanched The scale of the seanches has been increased dr-amatically since

1 9 9 2 , w h e n th e U S C o n g r - e s s v o t e d N A S A $ 1 O m i l l i o n p e n y e a n f o n te n y e a n s t o c o n d u c t athorough seanch for extna-tennestnial life Much of the money in this pnoject is being spent

on developing the special hardwane needed to search many fnequencies at once The projecthas two par-ts 0ne parl is a tar-geted seanch using the wor"ld's largest radio telescopes, lheAmenican-openated telescope in Arecibo, Puerto Rico and the Fr"ench telescope in Nancy

in Fnance This pant of the project is seanching lhe neanest l OOO likely stans with highsensitivity fon signals in the fnequency nange l OOO to 3OOO MHz The othen pant of theproject is an undinected seanch which is monitor-ing all of space with a lowen sensitivity, usingthe smallen antennas of NASAs Deep Space Networ"k

E

T h e r e is c o n s i d e n a b l e d e b a t e o v e r h o w w e s h o u l d n e a c t if w e d e t e c t a s i g n a l f n o m a n a l i e n

c i v i l i s a t i o n E v e r - y b o d y a g n e e s t h a t w e s h o u l d n o t r e p l y im m e d i a t e l y G u i t e a p a n t fr o m t h eimpr"acticality of sending a neply over such lar-ge distances at shor't notice, it raises a host

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Test 1

Quesfio ns 1 8-20

Choose NO MORE THAN THREE WORDS AND/OR A NUMBER from fhe pass age foreach answer

Write your answers in boxes 1B-20 on your answer sheet

18 What is the life expectancy of Earth?

1 9 W h a t k i n d o f s i g n a l s f r o m o t h e r in t e l l i g e n t c i v i l i s a t i o n s a r e S E T I s c i e n t i s t s s e a r c h i n g

f or?

20 How many stars are the world's most powerful radio telescopes searching?

Quesfio ns 21-26

Do the following statements agree with the views of the writer in Reading Passage 2?

ln boxes 21-26 on your answer sheet, write

yES if the statement agrees with the views of the writer

NO if the statement contradicfs the views of the writer

NOT GIVEN if it is impossible to say what the writer thinks about this

2 1 A l i e n c i v i l i s a t i o n s m a y b e a b l e to h e l p the human r a c e to o v e r c o m e s e r i o u s

p r o b l e m s

2 2 S E T I s c i e n t i s t s a r e tr y i n g t o f i n d a l i f e fo r m ' t h a t r e s e m b l e s h u m a n s i n m a n y w a y s

23 The Americans and Australians have co-operated on joint research projects

24 So far SETI scientists have picked up radio signals from several stars

25 The NASA project attracted criticism from some members of Congress

26 lf a signal from outer space is received, it will be important to respond promptly

24

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You should spend about 20 minufes on Quesfions 27-40, which are based on ReadingPassage 3 below

Tne nistoty ol the tortoise

If you go back far enough, everything lived

in the sea At various points in evolutionary

history enterprising individuals within

many different animal groups moved out

onto the land, sometimes even to the

most parched deserts, taking their own

private seawater with them in blood and

cellular fluids In addition to the reptiles,

birds, mammals and insects which we

see all around us, other groups that have

succeeded out of water include scorpions,

snails, crustaceans such as woodlice and

land crabs, millipedes and centipedes,

spiders and various worms And we

rnustn't forget the plants, without whose

prior invasion of the land none of the other

migrations could have happened

Moving from water to land involved

a major redesign of every aspect of life,

including breathing and reproduction

Nevertheless, a good number of

thoroughgoing land animals later turned

around, abandoned their hard-earned

terrestrial re-tooling, and returned to

the water again Seals have only gone

part way back They show us what the

intermediates might have been like, on

the way to extreme cases such as whales

and dugongs Whales (including the small

whales we call dolphins) and dugongs,

with their close cousins the manatees,

ceased to be land creatures altogether

and reverted to the full marine habits of

their remote ancestors They don't evencome ashore to breed They do, however,still breathe air, having never developedanything equivalent to the gills of theirearlier marine incarnation Turtles wentback to the sea a very long time ago and,like all vertebrate returnees to the water,they breathe air However, they are, in onerespect, less fully given back to the waterthan whales or dugongs, for turtles still laytheir eggs on beaches

There is evidence that all modernturtles are descended from a terrestrialancestor which lived before most of thedinosaurs There are two key fossilscalled Proganochelys quenstedlt andPalaeo chersi s ta\amp ay ensi s clatingfrom early dinosaur times, which appear

to be close to the ancestry of all modernturtles and tortoises You might wonderhow we can tell whether fossil animalslived on land or in water, especially ifonly fragments are found Sometimesit's obvious Ichthyosaurs were reptiliancontemporaries of the dinosaurs, with flnsand streamlined bodies The fossils looklike clolphins and they surely lived likedolphins, in the water With turtles it is alittle less obvious One way to tell is bymeasuring the bones of their forelimbs.Walter Joyce and Jacques Gauthier,

at Yale Llniversity, obtained threemeasurements in these particular bones

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Test 1

of 7I species of iiving turtles and tortoises

They usecl a kind of triangular graph paperr

to plot the three measurements against

one another All the land torloise species

formed a tight cluster of points in the upper

part of the triangle; all the water turtles

cluster in the lower part of the triangular

graph There was no overlap, except when

they aclded sonle species that spend time

both in water and on land Sure enough,

these amphibious species show up on the

triangular graph approximately half rn'ay

between the 'wet cluster' of sea turtles and

the 'dry cluster' of land tortoises The next

step was to detennine where the fossils

fell The bones of P cluertstedlr and P

tctlcrrn.paye'nsis leave us in no doubt Their

points on the graph are right in the thick

of the dry cluster Both these fossils were

dry-l:rnd tortoises They come from the era

before our turtles returned to the water

You might think, therefore, that modern

land tortoises have probably stayed on

land ever since those early terrestrial

times, as most n-rammals did after a few of

them went back to the sea But apparently

not If you draw out the family tree ofail modern turtles ancl tortoises, nearlyall the branches are aquatic Today'sland tortoises constitute a single branch,cleeply nestecl among branches consisting

of aquatic turtles This suggests thatmodern land tortoises have not stayed

on land continuously since the time of P.quettstedli and P talantpayensis Rather,their ancestors \ rere among those whowent back to the water, and they then re-emerged back onto the land in (relatively)nlore recent times

Tortoises therefore represent aremarkable double return In commonwith all manmals, reptiles ancl birds, theirremote ancestors were marine fish andbefore that various lltore or less worm-likecreatures stretching back, still in the sea, tothe primeval bacteria Later ancestors lived

on land and stayed there for a very largenumber of generations Later ancestors stillevolved back into the water and becantesea turtles And flnally they returned yetagain to the lancl as tortoises, some ofwhich now live in the driest of deserts

26

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Quesfio ns 27-30

Choose NO MORE THAN TWO WORDS from fhe passage for each answer

Write your answers in boxes 27-30 on your answer sheef"

27 What had to transfer from sea to land before any animals could migrate?

ln boxes 31-33 on your answer sheef, write

TRUE if the statement agrees with the information

FALSE if the statement contradicts the information

NOT GIVEN if there is no information on this

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Test 1

Quesfio ns 34-39

Complete the flow-chart below

Choose NO MORE THAN TWO WORDS AND/OR A NUMBER from fhe pass age foreach answer

Write your answers in boxes 34-39 on your answer sheef

Method of determining where the ancestors of

turtles and tortoises come from

Step 4Bones of P quenstedti and P talampayensis were examined in a similar way and the

71 species of living turtles and tortoises were examined and a total of 34

were taken from the bones of their forelimbs

O u t c o m e : T h e p o i n t s f o r th e s e s p e c i e s t u r n e d o u t to b e p o s i t i o n e d a b o u t 3 8

up the triangle between the land tortoises and the sea turfles

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Quesfio n 40

Choose the correct letter, A B, C or D

Write the correct letter in box 40 on your answer sheef

According to the writer, the most significant thing about tortoises is that

A t h e y a r e a b l e to a d a p t t o l i f e in e x t r e m e l y d r y e n v i r o n m e n t s

B t h e i r o r i g i n a l l i f e fo r m w a s a k i n d o f p r i m e v a l b a c t e r i a

C they have so much in common with sea turtles

D t h e y h a v e m a d e th e tr a n s i t i o n f r o m s e a to l a n d m o r e th a n o n c e

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t _ _

1 0 0 M e t r e s

3 0

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What games are popular i n y o u r c o u n t r y ? [ W h y ? ]

Do you play any games? [Why/Why not?]

You can make some notes to help

Do you think that any recent changes in the way people live have affected general

s h o p p i n g h a b i t s ? W h y is t h i s ?

3 2

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s E C T I O N 1 Quesfions 1-10

Complete the form below

Write ONE WORD AND/OR A NUMBER for each answer

Accommodation Form - Student Information

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S E C T I O N 2 Q u e s f i o n s 1 1 - 2 0

Quesfio ns 1 1-1 3

Complete the table below

Write NO MORE THAN THREE WORDS for each answer

Parks and open spaces

H a l l a n d C o m m o n source of River Ouse 2 4 h o u r s

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Test 2

Quesfio ns 17-20

Label the map below.

Write the correct letter, A-1,

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s E C T l O N 3 Q 〃e s Ⅱo 刀s 2 仁3 0

Qt/es″ O门s2彳一 2亻

C f l o o s e r 幻 e c O r r e c r ∫ e r r e 巧 ^ , B o r c

Self-Access Gentre

21 Students want to keep the Self-Access Centre because

A they enjoy the variety of equipment

B t h e y li k e b e i n g a b l e to w o r k o n t h e i r o w n

C i t i s a n i m p o r t a n t p a r t o f t h e i r s t u d i e s

22 Some teachers would prefer to

A close the Self-Access Centre

B move the Self-Access Centre elsewhere

C restrict access to the Self-Access Centre

2 3 T h e s t u d e n t s ' m a i n c o n c e r n a b o u t u s i n g t h e li b r a r y w o u l d b e

A the size of the library

B d i f f i c u l t y i n g e t t i n g h e l p

C t h e la c k o f m a t e r i a l s

24 The Director of Studies is concerned about

A the cost of upgrading the centre

B t h e la c k o f s p a c e in t h e c e n t r e

C the difficulty in supervising the centre

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Test 2

Quesfio ns 25-30

Complete the nofes below.

Write NO MORE THAN TWO WORDS for each answer.

Necessary improvements to the existing Self-Access Centre

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sECTION4 Q″esJOns3仁亻o

Write ONE WORD ONLY for each answer

l a r g e , m a n y 3 5 s p e c i a l i s e d d e p a r t m e n t s r u l e s a n d p r o c e d u r e , e g j o b

3 6 a n d r u l e s f o r

d i s c i p l i n e

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l i k e s t o w o r k in g r o u p s

4 0

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6 the estimated proportion of children in New Zealand with auditory problems

Quesfio ns 7-10

Choose NO MORE THAN TWO WORDS AND/OR A NIJMBER from fhe pass age foreach answer

Write your answers in boxes 7-10 on your answer sheet

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Test 2

Quesfio ns 11 and 1 2

Choose TWO letters, A-F

Write the correct letters in boxes 11 and 12 on your answer sheef

The list below includes factors contributing to classroom noise

Which TWO are mentioned by the writer of the passage?

Choose the correct letter, A, B, C or D

Write the correct letter in box 1 3 on your answer sheef

What is the writer's overall purpose in writing this article?

A to compare different methods of dealing with auditory problems

B t o p r o v i d e s o l u t i o n s f o r o v e r l y n o i s y l e a r n i n g e n v i r o n m e n t s

C to increase awareness of the situation of children with auditory problems

D to promote New Zealand as a model for other countries to follow

44

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Iune 2004 saw the first passage, known as a'transit',

of the planet Venus across the face of the Sun in

122 years Transits have helped shape our view of

the whole Universe, es Heather Cooper and l,{igel

Henbest explain

On 8 |une 2004, more than half the population of the world were treated to a rareastronomical event For over six hours, the planet Venus steadily inched its way over thesurface of the Sun This'transit'of Venus was the first since 6 December 1882 On thatoccasion, the American astronomer Professor Simon Newcomb led a party to SouthAfrica to observe the event Th.y were based at a girls' school, where - it is alleged - thecombined forces of three schoolmistresses outperformed the professionals with theaccuracy of their observations

For centuries, transits of Venus have drawn explorers and astronomers alike to thefour corners of the globe And you can put it all down to the extraordinary polymathEdmond Halley In November 1677,Halley observed a transit of the innermost planet,Mercury, from the desolate island of St Helena in the South Pacific He realised that,from different latitudes, the passage of the planet across the Sun's disc would appear todiffer By timing the transit from two widely-separated locations, teams of astronomerscould calculate the parallax angle - the apparent difference in position of an

astronomical body due to a difference in the observer's position Calculating this anglewould allow astronomers to measure what was then the ultimate goal: the distance ofthe Earth from the Sun This distance is known as the'astronomical unit'or AU

Halley was aware that the AU was one of the most fundamental of all astronomicalmeasurements |ohannes Kepler, in the early 17th century, had shown that the

distances of the planets from the Sun governed their orbital speeds, which were easilymeasurable But no-one had found a way to calculate accurate distances to the planetsfrom the Earth The goal was to measure the AU; then, knowing the orbital speeds ofall the other planets round the Sun, the scale of the Solar System would fall into place.However, Halley realised that Mercury was so far away that its parallax angle would bevery difficult to determine As Venus was closer to the Earth, its parallax angle would be

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Sun's distance to 1 part in 500 But there was a problem: transits of Venus, unlike those

of Mercury, are rare, occurring in pairs roughly eight years apart every hundred or soyears Nevertheless, he accurately predicted that Venus would cross the face of the Sun

in both 17 6l and I 7 69 - though he didn t survive to see either

Inspired by Halley's suggestion of a way to pin down the scale of the Solar System,teams of British and French astronomers set out on expeditions to places as diverse asIndia and Siberia But things werent helped by Britain and France being at war Theperson who deserves most sympathy is the French astronomer Guiilaume Le Gentil

He was thwarted by the fact that the British were besieging his observation site atPondicherry in India Fleeing on a French warship crossing the Indian Ocean, Le Gentilsaw a wonderful transit - but the ship's pitching and rolling ruled out any attempt atmaking accurate observations Undaunted, he remained south of the equator, keepinghimself busy by studying the islands of Mauritius and Madagascar before setting off

to observe the next transit in the Philippines Ironically after travelling nearly 50,000kilometres, his view was clouded out at the last moment, a very dispiriting experience.While the early transit timings were as precise as instruments would allow, the

measurements were dogged by the 'black drop' effect When Venus begins to cross theSun'.s disc, it looks smeared not circular - which makes it difficult to establish timings.This is due to diffraction of light The second problem is that Venus exhibits a halo oflight when it is seen just outside the Suns disc While this showed astronomers thatVenus was surrounded by a thick layer of gases refracting sunlight around it, botheffects made it impossible to obtain accurate timings

But astronomers laboured hard to analyse the results of these expeditions to observeVenus transits Johann Franz Encke, Director of the Berlin Observatory, finally

determined a value for the AU based on all these parallax measurements:

153,340,000 km Reasonably accurate for the time, that is quite close to today's value of149,597,870 km, determined by radar, which has now superseded transits and all othermethods in accuracy The AU is a cosmic measuring rod, and the basis of how we scalethe Universe today The parallax principle can be extended to measure the distances tothe stars If we look at a star in January - when Earth is at one point in its orbit - it willseem to be in a different position from where it appears six months later Knowing thewidth of Earth's orbit, the parallax shift lets astronomers calculate the distance

June 2004's transit of Venus was thus more of an astronomical spectacle than a

scientifically important event But such transits have paved the way for what mightprove to be one of the most vital breakthroughs in the cosmos - detecting Earth-sizedplanets orbiting other stars

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Look at the following statements (Quesfions 1B-21) and the tist of people below.

Match each statement with the correct person, A, B, C or D

Write the correct letter, A, B, C or D, in boxes 1B-21 on your answer sheet

1 8 H e c a l c u l a t e d t h e d i s t a n c e o f t h e S u n fr o m th e E a r t h b a s e d o n o b s e r v a t i o n s o fVenus with a fair degree of accuracy

19 He understood that the distance of the Sun from the Earth could be worked out by

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