Astronomy. Mark Scheme 1. Save My Exams! The Home of Revision For more awesome GCSE and A level resources, visit us at

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1 Astronomy Mark Scheme 1 Level Edexcel Subject Physics Exam Board GCSE(9-1) Topic Astronomy Sub Topic Booklet Mark Scheme 1 Time Allowed: Score: Percentage: 58 minutes /48 /100

2 Answer For more awesome GCSE and A level resources, Acceptable visit us at answers Mark 1(a) C Herschel discovered infrared radiation 1(b)(i) (km) (even if calculated value from this is incorrect) accept (b)(ii) An explanation linking any two of 1. change of relative positions in orbits on same side and opposite sides of Earth may be shown by calculation or diagram (2) 2. different radii orbits different distances (from Earth) moon is further away 3. different (orbital) {speeds / times} (moon/hubble) moves faster than other mention of {not perfect circle / elliptical / different orbital planes} on its own is insufficient needs qualifying one moves faster than the other and overtakes it = 2 marks 1(c)(i) Correct plotting +/- ½ a small square if line is drawn exactly through the point accept for the mark even if point is not obvious

3 1(c)(ii) Line of best fit drawn straight line to be within lower two printed dots and upper 3 printed dots does not need to pass through origin ignore line below the given points 1(d) A description including (2) 1. expansion (of space) and any one of 2. continuing (expansion) ignore expansion of Earth, particles and other objects unqualified explosion is insufficient, a reference to expansion is needed (this point only is dependent on first) 3. from very {hot/dense} start 4. from a {point /small volume} 5. origin of Universe singularity {Universe / Space} still expanding = 2 marks Total for 2 = 8 marks

4 2(a)(i) X amplitude (2) Y wavelength 2(a)(ii) A 2(b)(i) mirror linked to: (which is) converging / concave / parabolic reflector (reflection / reflects is insufficient) curved ignore any reference to lenses, converging lenses and eyepieces (2) 2(b)(ii) magnifies makes it (look) bigger ignore closeness, clearness, more detail etc. ignore focus the image ignore zoomed in

5 QWC *2 (c) Indicative Content A description including some of the following points evidence for idea of Sun, Moon, stars or planets moving across the sky (not just orbiting) in the same direction pattern is repeated appear to be going around the Earth same every day evidence against moons of {Jupiter/ other planet (with moons)} appear to {orbit/ go around} {Jupiter/ other planet} movement of Sun etc. not quite the same each day planets do not move in a simple path retrograde (west-east) motion of planets If no other marks scored heliocentric model = Level 1 Mark (6) Level 0 No rewardable content a limited description stating one fact for or against e.g. for the Sun / stars move across the sky OR against - Jupiter has moons OR against - (Galileo) produced the {heliocentric / sun-centred} model the answer communicates ideas using simple language and uses limited scientific terminology e.g. some correct names for the moving objects spelling, punctuation and grammar are used with limited accuracy a simple description involving (linked) facts e.g. the Sun and stars move across the sky AND do the same thing each day OR moons orbit Jupiter OR one fact for AND one against e.g. the sun moves across the sky but changes from day to day the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately e.g. correct names for the moving objects spelling, punctuation and grammar are used with some accuracy a detailed description of arguments for AND against, including at least one link. e.g. the Sun and stars move across the sky. Galileo observed moons, which orbit Jupiter. the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors Total for 5 = 12 marks

6 3(a)(i) Description including any two of: (2) gravity (causes the) nebula to collapse/contract (causes the) temperature to increase Pulls {particles/gas} together Forms protostar ke transferred to thermal energy KE/GPE ->thermal GPE -> KE until it was hot enough to start the reaction until fusion starts 3(a)(ii) D white dwarf 3(b)(i) Y drawn anywhere to the right of X e.g Accept any clear indication of where line should be line doesn t have to be labelled Reject lines both sides of X 3(b)(ii) explanation linking: (distant) galaxy moving away (2) (so) line shifted to longer λ shifted to red/redshift/lower frequency λ (appears to be) increasing Do not allow: galaxy appears red λ and f contradictions

7 3(c)(i) 3(c)(ii) D..is expanding... did not have a beginning Cosmic Microwave Background (Radiation) [order of words unimportant] CMB(R) reject CMB and red shift Total for 2 = 8 marks

8 4(a)(i) B red giant 4(a)(ii) C the Milky Way 4(a)(iii) D Proxima Centauri 4(b) description to include: method Telescope (inc. radio telescopes) Lander (e.g. robots/drones) Orbiter / Satellite relevant detail has camera / takes photos / collecting samples (e.g rocks) / analyse atmosphere / climate / signs of water / gases that will support life / can test for water/nutrients ignore repeat of stem (2)

9 4(c)(i) explanation linking two from: (on Earth) image is distorted / image not bright enough (ORA) Reverse arguments apply throughout (above atmosphere gives) more defined / clearer / better image planets very small / far away atmosphere (in way) / light pollution can detect different parts of em spectrum (that are not detectable on Earth) obscured by clouds waves can be detected (that are not detectable on Earth) can keep it pointed at the same spot more easily not affected by Earth s rotation (2) 4(c)(ii) Suggestion: planet takes 150 days to orbit the star has 150 days in a year (Total for 2 = 8 marks)

10 5 (a)(i) A a black hole 5 (a)(ii) A description including three from: gas / gas and dust MP1 in a nebula MP2 (particles) attracted / come together by (force of) gravity MP3 pe/ke transferred to thermal/heat energy (gas begins to glow and forms protostar) MP4 until {hot / pressure / dense} enough to start nuclear reaction /fusion core becomes hot / pressure increases / density increases until fusion of hydrogen starts hydrogen starts to become helium condone hydrogen burning (3) 5 (a)(iii) A suggestion involving two from: MP1 the oldest star had not yet appeared when the {Big Bang happened / universe started} MP2 the Universe is older than the oldest star MP3 star takes time to form MP4 can t be certain of this time stars formed after the Big Bang the age of the oldest star is the minimum age of the Universe estimation is not the same as accurate measurement can t be sure there isn t an older star (2)

11 Indicative Content QWC *5( ) An explanation including some of the following points Mark light shifted to red end of spectrum light waves are stretched so wavelength increases reference to black or spectral lines moving to red end (of absorption spectrum) frequency of wave from a moving source changes decrease in frequency means source moving away increase in frequency means source moving towards us red shift shows galaxies are moving away from us greater red shift indicates galaxy moving away faster further away galaxies give greater red shift (nearly) all galaxies show red-shift red shift shows decrease in frequency blue shift shows increase in frequency therefore galaxies are moving apart [mention of Doppler effect] [outline of Doppler effect] (6)

12 Level No rewardable content a limited explanation e.g. (light from) {galaxy / planet /object} moving away from us is shifted to red end of the spectrum OR red shift means {galaxy / planet /object) is moving away from us the answer communicates ideas using simple language and uses limited scientific terminology e.g. correct use of change of colour and movement spelling, punctuation and grammar are used with limited accuracy a simple explanation involving detail of meaning of different red shifts OR involving frequency / wavelength e.g. red shift shows galaxies moving away from us. More distant galaxies give greater red shift showing they are travelling faster away. OR light from galaxies/stars moving away is shifted to red end of the spectrum because of an (apparent) {increase in the wavelength/decrease in the frequency} (of light). the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately e.g. correct use of the terms galaxy/star, frequency, wavelength spelling, punctuation and grammar are used with some accuracy a detailed explanation correctly interpreting the (apparent) drop in frequency / increase in wavelength e.g. light from (most) galaxies is shifted towards the red end of the spectrum because of an {increase in the wavelength/decrease in the frequency}. This indicates that (most) galaxies are moving away from us, hence showing the Universe is expanding the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately e.g. linkages must be clear between red-shift, movement and expansion of the Universe spelling, punctuation and grammar are used with few errors (Total for 6 = 12 marks)

13 Astronomy Mark Scheme 2 Level Edexcel Subject Physics Exam Board GCSE(9-1) Topic Astronomy Sub Topic Booklet Mark Scheme 2 Time Allowed: Score: Percentage: 51 minutes /42 /100

14 1(a)(i) Milky Way Accept any spelling 1(a)(ii) D white dwarf 1(b)(i) (2) Mercury Venus Mars km km km Three correct (2) One or two correct + or one square Judge by eye

15 1(b)(ii) Correct information from table 1.52 Seen anywhere in the answer (2) Conversion to kilometres (1.52) x Incorrect information shown to be used correctly Correct answer, no working scores full marks / 2.28 x 10 8 (km) 228 to any power of 10, allow 1 mark if no other mark awarded / 2.25 x 10 8 (km), allow max 1 mark if no working shown.

16 Indicative Content QWC * ) A description including some of the following points Mark In Solar System Use of telescopes Search for evidence of conditions needed for life e.g. water/oxygen/bacteria on other planets Manned missions (to the Moon) Unmanned missions/probes to other planets e.g. Mars, Jupiter, Saturn, Mercury Landers / robots / rovers sample soil Information transmitted back to Earth Throughout the Universe Search for extra-terrestrial intelligence (SETI) Use radio telescopes Search for (regular pattern of) radio signals Search for other planetary systems Discovery of other planetary systems (capable of supporting life) Broadcasting signals/ sending out messages (to extra terrestrial intelligences) (6) Level 0 No rewardable content A limited description giving a (named) way of searching for evidence e.g. SETI OR using telescopes OR send messages to space OR spacecraft The answer communicates ideas using simple language and uses limited scientific terminology Spelling, punctuation and grammar are used with limited accuracy A simple description of any TWO of the searches for evidence e.g space probes go to other planets and telescopes are used OR radio telescopes and looking for radio waves from space. The answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately Spelling, punctuation and grammar are used with some accuracy A detailed description of searches for evidence within AND outside the solar system e.g. Unmanned space probes go to other planets and radio telescopes search for radio signals from space. The answer communicates ideas clearly and coherently uses a range of scientific terminology accurately Spelling, punctuation and grammar are used with few errors

17 2(a)(i) cosmic microwave background (radiation) all three words needed 2(a)(ii) (the) Big Bang (theory) 2(a)(iii) change in the (observed) frequency or wavelength of light/radiation (received from a distant galaxy) light/absorption lines is/are shifted toward red end of spectrum light/radiation has longer wavelength/lower frequency waves are more spread out/stretched Ignore references to sound or colour of light eg galaxies/light appear(s) red(er) 2(a)(iv) An explanation linking the following:- It/the Universe is expanding they/ galaxies are moving further/away (from the Earth/us) some galaxies are (moving)faster (than others) the further away the galaxy is the greater the red-shift/the faster the galaxy is moving (some galaxies) are moving away faster (than others) gains 2 marks (2) IGNORE references to planets/stars 2(b)(i) D red giant then white dwarf

18 2(b)(ii) an explanation linking two of the following: Different/more wave(length)s/frequencies (now) detected/collected because telescopes positioned above Earth s atmosphere or by radio telescopes named type of em radiation accept CMB for microwave space telescope or named space telescope OR weaker signal(s) (now) detected/collected because modern telescopes are more powerful/have greater magnification or positioned above Earth s atmosphere/ on top of mountains (because) less or no light/radiation is absorbed by Earth's atmosphere Accept named space telescope eg Hubble/Planck/Compton etc If no other marks awarded allow 1 mark for idea that: Electronic(s)/computers can process/improve the data/signal information/waves/radiation Ignore references to clearer images/more detail/can see further/photographs (2)

19 3(a)(i) Universe 3(a)(ii) Milky Way 3(b)(i) A description including: change in wavelength / frequency Correct change(s) wavelength increases (2) frequency decreases (2) (2) 3(b)(ii) An explanation linking two of the following points red shift universe expanding (cosmic) microwave (background)(radiation) Accept initials (eg CMB) (2)

20 Indicative content QWC *3(c) A description including some of the following points Mark Life cycle of a star similar of mass similar to that of our sun a. nebu / stellar nursery clouds of dust and gas pulled together or collapsed by gravitational forces b. Ou sun / main sequence stable state hydrogen being converted to helium, nuclear fusion huge amounts of heat and light produced continues for many millions of years c. r giant hydrogen runs out star expands star gets colder uses up all its helium outward forces decrease d. white dwarf eventually collapses due to own gravity becomes much smaller and very dense e. Sequ ce: Nebula / stellar nursery (Protostar) Star (main sequence) Red Giant White Dwarf (Black Dwarf) ignore references to planetary nebula) Credit is given for correctly labelled diagrams. Level 0 no rewardable material (6) 1 1- a limited description including naming one of the stages (star alone is insufficient) e.g. A star can be a red giant the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy 2 3- a simple description including two consecutive stages in the correct sequence OR a description of one of the stages e.g. a nebula forms a (main sequence) star / Nebulae are clouds of dust and gas the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy a detailed description including naming three consecutive stages in the correct order AND a description of one stage e.g. A nebula is a cloud of gas and dust that forms a star which then becomes a red giant. the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors

21 4(a)(i) the explosion of a massive star 4(a)(ii) Answer longest wavelength shortest wavelength Mark infrared visible light X-rays All three must be correct 4(a)(iii) An explanation linking three of the following points discovery of objects not detectable by visible light more information / data can be collected different (electromagnetic) waves can give different types of information produce magnified images (space telescopes) produce clearer images / images unaffected by Earth s atmosphere allow specific examples e.g. (discovery of) black holes/cmb / pulsars different telescopes provide different data/ images brighter/more detailed images ignore idea can see further unless qualified (3)

22 4(b) Any two of the following points Spitzer observes /uses infrared ignore idea to protect telescope from heat/damage infrared is heat Sun produces (large amounts of) heat / infrared small amount of heat from distant galaxies would not be detected (amongst radiation from the Sun) infrared (waves)/heat from the Sun would interfere with/swamp/ruin image (of distant galaxies) (2) 4(c)( i) calculate one distance accept or e.g x 10 8 or 3.96 x evaluation e.g. (3.96 x x 10 8 ) = e.g. inverse (1.49 x x ) 3.77 x 10-6 e.g. from comparison of times ( ) = Give 2 marks for a correct evaluation with no working shown or no distance calculation Give 2 marks for two correct distances and a correct comparative statement (2) 4(c)(ii) the stars are so distant that a large unit of distance is needed the numbers (of km or miles) would be too big (to understand)/ too long (to write down) (numbers of) light years are more manageable/ easier to understand

23 Astronomy Mark Scheme 3 Level Edexcel Subject Physics Exam Board GCSE(9-1) Topic Astronomy Sub Topic Booklet Mark Scheme 3 Time Allowed: Score: Percentage: 53 minutes /44 /100

24 1(a)(i) A 1(a)(ii) A description including any two of the following above the/no atmosphere above the clouds / no clouds/no weather image is clearer/ more detailed/ not distorted/not blurred no light pollution no absorption (by atmosphere) of other named radiations e.g. X- rays no air/dust/pollution can see further /wider field of view/can use anytime IGNORE it is closer (to the stars/planets) IGNORE references to improving understanding / knowledge of space (2) 1(b)(i) Either one of the following radio (waves) microwaves

25 1(b)(ii) a description including any two of the following collect more information / waves /data greater resolution /detail/ magnification other regions of the EM spectrum are used mention of specific data e.g. black holes/ red shift discover /new planets/stars/ galaxies etc (see) clearer/better images /closer view (can) see further (into space)/ smaller objects accept idea that they are not restricted to light e.g. (can) detect radiation /radio waves (from Big Bang/stars)/CMB IGNORE any references to hearing. (2) 1(c)(i) (cloud of) dust and/or gases Accept hydrogen/helium Accept idea that it is where stars/planets are formed Ignore rocks/smoke

26 1(c)(ii) A description linking three of the following when nebula reaches a critical mass correct sequence is not required when nebula or dust/gas cloud is big (enough) nebula collapses/contracts (due to) gravitational attraction (gets) hot/ (makes) heat gases/dust/nebula come together/pulled together/spiral /move faster gravity/gravitational (potential) energy transformed into thermal energy ignore starts to burn/explodes/friction forms a protostar emits/produces light /radiation starts nuclear reaction/fusion/ hydrogen turns into helium/new elements (3)

27 6(a)(i) B 2(a)(ii) radio waves are not absorbed by the atmosphere not affected by {light pollution / clouds} 2(a) (iii) an explanation including two of the following 1 mm waves are in the microwave region which is (completely) absorbed by atmosphere space flight enabled telescopes to be put above atmosphere /in space they are microwaves cannot be (easily) detected on Earth we needed to go above atmosphere / into space (2) 2(a)(iv) an explanation linking the following light might be shifted into infrared region (some) infrared is (strongly) absorbed by atmosphere (2)

28 Indicative For more awesome content GCSE and A level resources, visit us at QWC *2(b) A description to include some of the following facts: Mark observation of visible light led to discovery of red-shift. galaxies are moving away from each other CMBR detected in radio telescopes space telescopes (such as COBE) gave more detail of CMBR Big Bang and Steady State theories were proposed distances to galaxies could be determined Big Bang could explain red-shift Steady State could explain red-shift The description gives some of the following details: red-shift means lower frequency / longer wavelength red-shift was greatest for the most distant galaxies red-shift means universe is expanding Big Bang / Steady State can explain an expanding universe only Big Bang could explain CMBR CMBR is residual radiation from the Big Bang The description gives some of the following reasons for scientists beliefs observation of increasing red-shift with distance is a reason to believe in expanding universe (6) Level 0 No rewardable material 1 1- a limited description of either red-shift or CMBR, e.g. light from galaxies was red-shifted OR Red-shift is evidence for Big bang. the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy 2 3- a description giving full detail of either red-shift or CMBR OR some detail of both red-shift and CMBR, e.g. light was seen to be shifted towards a longer wavelength. This means that the galaxies are moving away from each other. the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy a detailed description of how both red-shift and CMBR give supporting evidence for the Big Bang theory, e.g. light was seen to be shifted towards a longer wavelength. This means that the galaxies are moving away from each other so the Universe must be expanding. This is evidence for the Big Bang theory. Cosmic Background Radiation coming from all directions provides further evidence for the Big Bang. the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors

29 3(a) D the Universe 3(b) (nebula) main sequence (star) AND red giant white dwarf All three in correct order for 2 marks Red Giant White Dwarf (Main sequence) (2) 3(c)i infrared (radiation)/(rays)

30 3(c)ii An explanation linking any two from Credit to be given for stating that all telescopes would be better in space, but size and weight may exclude e.g. Jodrell Bank from space. above the clouds / no clouds/ no weather image is clearer/more detailed/ not distorted/not blurred no {air/dust/pollution} wider field of view/ can use anytime no light pollution (some) telescopes use gamma/ X-rays/ultraviolet /infrared/microwaves (2) no absorption (by atmosphere) of gamma/ X- rays/ultraviolet /infrared/ microwaves IGNORE see further IGNORE it is closer (to the stars/planets) IGNORE: references to improving understanding / knowledge of space

31 Indicative Content QWC 3(d) A description including some of the following points Mark improved QUALITY eg higher or better magnification/ detail/resolution or clearer/brighter image OR MORE INFORMATION (than with naked eye) of image/data eg new planets/stars/nebulae/pulsars (This could be extra detail for greater magnification/resolution only) detection of (non-visible) electromagnetic WAVES eg X- ray / UV / IR/ radio TECHNOLOGY that enable collection of more data eg reflecting telescope/arrays and/or additions eg computer-aided /photographic connections or larger (objective) lens/mirror (6) Exp POSITION of telescopes eg orbital/outside atmosphere/on top of mountains/away from atmosphere/rays not absorbed/obscured/scattered by atmosphere. Ignore Hubble or Compton. Level 0 No rewardable content a limited description e.g. mention of any one example such as magnifies stars/planets OR discovering new planets/stars the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy a simple description e.g. mention of either two of the improvements OR extra detail about one of the improvements eg improvement plus example (ie Magnifies planets so that craters/mountains may be seen) the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy a detailed description e.g. mention of three (or more) improvements OR two improvements plus extra detail about one of them (ie Telescopes in space can detect X- Rays that would be absorbed by the atmosphere) the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors (Suitable extra detail shown in italics in examples above) Total for 5 = 12 marks

32 4(a) D 4(b) An explanation linking any two of Accept reverse argument (presence of Earth s ) atmosphere causes light to be absorbed/reduced in intensity causes distortion of the image (more) light pollution (bigger) variations in temperature (more) air/ clouds/ pollution/ dust blocked / (more) difficult to see through blurs the image / refracts the light (2) 4(c) An explanation linking any three of galaxies moving away from Earth / Sun galaxy 2 (moving away) faster (than galaxy 1) galaxy 2 is (likely to be) most distant galaxy galaxies are (moving) at different speeds / away from each other / universe is expanding (3)

33 4(d) A description including the following stages (up to 3 marks) Protostar Main sequence star (super) red giant supernova neutron star (4) (even more massive star can become) black hole more massive stars have shorter life Three stages in the correct sequence

34 Astronomy Mark Scheme 4 Level Edexcel Subject Physics Exam Board GCSE(9-1) Topic Astronomy Sub Topic Booklet Mark Scheme 4 Time Allowed: Score: Percentage: 56 minutes /46 /100

35 1(a) A 1(b) C 1(c) reference to the connection between water and life water is needed for life see if we could live there could sustain life water gives possibility of life a definite statement that water shows life scores ZERO e.g. prove that there is life there shows signs of life 1(d) substitution e.g evaluation 3 (00 000) evaluation consistent with unit (km/s) Ignore powers of ten e.g. bald = 2 bald 0.3 = 2 give full marks for correct answer, no working { m/s (with some working) = 3 marks bald m/s =2} (3)

36 1(e)(i) An explanation linking any two from (telescope {above / out of}) {atmosphere/air} dust/clouds/obstructions etc (in atmosphere) no light pollution in space (2) 1(e)(ii) An explanation linking the following pulled together by gravity (converting) {potential / kinetic} energy to {thermal/heat} collisions create friction (not bald friction) friction produces {thermal/heat} (very) high pressure produced (2)

37 2(a)(i) A description including three of the following points Accept description of the process {gravitational (potential) energy / GPE} of gas and dust (GPE) changes to kinetic energy (ke) changes to thermal/heat/light (hot enough to release) nuclear energy {gas and dust / it / nebula} pulled together by gravity (particles) move faster core becomes hot (hot enough for) nuclear fusion/reaction accept description shown as chain gpe ke thermal nuclear (3) 2(a)(ii) A description including the following points reference to stars of different sizes {Sun/small/medium} becoming {white / black} dwarf more massive becoming a neutron star / black hole Sun and more massive/bigger star red giant / planetary nebula (red) supergiant / supernova (3)

38 Indicative content QWC *2(b) A discussion linking some of the following points Mark red shift CMB linked to movement both theories have expanding Universe redshift support both linked to ageing Universe Big Bang ageing, SS not CMB supports Big Bang only because only Big Bang has single origin (6) Level 0 no rewardable material 1-2 a limited discussion stating both pieces of evidence or limited detail about either red shift or CMB e.g. change in wavelength /red shift shows galaxies / stars moving away the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy 2-4 a simple discussion including both pieces of evidence and simple detail about either red shift or CMB e.g. a change in wavelength shows galaxies / stars moving away the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy a detailed discussion describing both pieces of evidence and drawing a conclusion e.g. a change in wavelength shows galaxies / stars moving away and CMB shows Universe has been changing with time and redshift supports both theories, CMB supports only Big Bang because Steady State has constant Universe the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors

39 3(a)(i) C 3(a)(ii) telescope (astronomical/refracting/light) telescope IGNORE any other type of telescope 3(b)(i) 4 (June) 4-6; 6-4 (UK/US dates) 20 (June); 20-6; (b)(ii) 16 (days) 3(b)(iii) (km) (2) OR (km) (2) OR {2 x } (km) (2) Power of 10 error max 1 mark Use of and (km)/ Use of and 2 x (km)/ 12 June marked correctly on the orbit for Ganymede/ answer of 399,000 with no working (2) gets 1 mark

40 QWC * ) (iv) Indicative Content A description including some of the following points reasons for the distance changing appreciation of a difference in time/speed/size of orbit smallest separation on 4/20 th June smallest separation km largest separation km largest separation on 12/28 June moon separation increases after 4 th June. Mark (6) distance between moons increases and then decreases as they orbit distance increased after 4 June which was smallest separation of km Distance increases from a minimum on4 th June to a maximum on 12 th June, back to a minimum on 20 th June and maximum on 28 th June distance change is not linear Leve 0 No rewardable content l a limited description giving 1 relevant piece of information taken from the diagram e.g. Europa orbits in a shorter time OR The moons have different sized orbits OR Europa orbits in 8 days the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy a simple description giving either the size or the date of smallest or largest separation OR giving increase and/or decrease of separation e.g. The moons are closest on the 4 th June OR Moon separation increases after 4 th June OR the distance between the moons increases then it decreases the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy a detailed description indicating an increase and decrease in separation plus a date or distance OR describes 3 orbits e.g. The distance between the moons increases till 12 June then it decreases OR the distance between the moons increases, then decreases, then increases again the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors

41 4(a)(i) Any one of radio visible microwave infrared / IR ultraviolet / UV 4(a)(ii) Any one of X-ray gamma ray far infrared infrared / IR ultraviolet / UV 4(b)(i) N = 39 (A.U.) P = 77 (A.U.) range inclusive range inclusive (2) 4(b)(ii) An explanation linking actual value for Neptune is {different from / lower than} predicted value actual value for Neptune put on to chart by cross or dot etc. (no need for label) with one of these (so) the rule does not work (for Neptune) (Neptune) is an anomaly the rule gives too high a value (so) Neptune might have been {captured / entered} from outside the original Solar System ignore references to age of Neptune (2)

42 Indicative Content QWC *4(c) A discussion including some of the following points Mark Methods o space probes o soil experiments by landers o SETI o telescopes o robotic machines Problems expense / international collaboration needed large distances involved o if problem difficult to correct o time to react to problem is long o time to respond to any communication would be long o complex technology for human visit for robot investigation fuel recognition of alternative life-forms pattern recognition o for SETI o communication if intelligent life-form (6) possibility of cross-contamination Level 0 No rewardable content a limited discussion including EITHER two named problems, OR two named methods, OR a named problem + a named method e.g. It would be expensive and the distances are large OR Space probes and SETI can be used OR can listen for communications, life beyond Earth may not be water based. the answer communicates ideas using simple language and uses limited scientific terminology. spelling, punctuation and grammar are used with limited accuracy a simple discussion including EITHER a problem with its associated method + some other named problem OR a detailed problem + one other named problem e.g. It is expensive to send a space probe to Mars; the distance to Mars very large OR It is difficult to search through the data from space because there is a huge amount of it. Also, any message would be hard to decode. the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately. spelling, punctuation and grammar are used with some accuracy.

43 3 5 6 a detailed discussion including EITHER two problems with their associated method(s) + some other named problem OR two detailed problems + one other named problem OR a problem with its associated method + a detailed problem + one other named problem e.g. We can analyse radiowaves from space, but they take so long to arrive that the aliens that sent them could have already died out. It is very expensive to develop the technology needed to go to other planets. Also, we might not recognise alien life-forms there. OR It is difficult to search through the data from space because there is a huge amount of it. Radiowaves in space take a long time to arrive because the distances are so vast. It all costs a lot of money. OR It is very expensive to develop the technology needed to go to other planets. It is difficult to search through the data from space because there is a huge amount of it. Also, we might not recognise alien life-forms there. the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately. spelling, punctuation and grammar are used with few errors.

44 Astronomy Mark Scheme 5 Level Edexcel Subject Physics Exam Board GCSE(9-1) Topic Astronomy Sub Topic Booklet Mark Scheme 5 Time Allowed: Score: Percentage: 42 minutes /35 /100

45 number Answer Additional guidance Mark 1(a) An explanation that combines identification understanding (1 mark) and reasoning/justification understanding (2 marks): allow valid alternatives, e.g. references to comets at the time, there was only naked eye evidence which indicated Sun/Moon/planets appear to move across the sky in the same direction, same motion each day (3) number 1(b) Answer Additional guidance Mark An explanation that combines identification understanding (1 mark) and reasoning/justification understanding (2 marks): both theories predict an expanding universe and the Big Bang theory also predicts that the universe had a beginning the red shift theory indicates that the universe is expanding so supports both theories whereas CMB also indicates that the universe had a beginning, so supports Big Bang theory provided evidence that the steady state theory was incorrect (3)

46 number Answer Mark 1(c)(i) B number Answer Mark 1(c)(ii) B number 1(d) Answer An explanation that combines identification via a judgement (1 mark) to reach a conclusion via justification/reasoning (2 marks): galaxy C is furthest away because it has the greatest red shift and therefore it has the greatest speed Mark (3)

47 number 2(a) Answer Additional guidance Mark An explanation that combines identification understanding (1 mark) and reasoning/justification understanding (2 marks): allow valid alternatives, e.g. references to comets at the time, there was only naked-eye evidence which indicated Sun/Moon/planets appear to move across the sky in the same direction, same motion each day (3)

48 number 2(b) Answer Additional guidance Mark An explanation that combines identification understanding (1 mark) and reasoning/justification understanding (2 marks): both theories predict an expanding universe and the Big Bang theory also predicts that the universe had a beginning the red shift theory indicates that the universe is expanding so supports both theories whereas CMB also indicates that the universe had a beginning, so supports Big Bang theory provided evidence that the Steady State theory was incorrect (3) number 2(c)(i) Answer B Mark number 2(c)(ii) Answer B Mark

49 number 3(a)(i) Answer An explanation that combines identification via a judgement (1 mark) to reach a conclusion via justification/reasoning (2 marks): Mark galaxy C has the greatest red shift so this galaxy has the greatest speed since the galaxy with the greatest speed will be furthest away, then galaxy C is at the furthest distance (3)

50 number Answer Additional guidance Mark 3(a)(ii) 20 (nm) Allow answers in the range 19 to 25 number Answer Additional guidance Mark 3(a)(iii) Substitution v = 8 9 ( 3 10 ) ( ) ( ) Answer = (m/s) allow ecf from (c)(i) power of 10 error = max 1 accept (m/s) award full marks for correct numerical answer without working (2) number 3(b) Answer Additional guidance Mark Any two from the following improvements: allow use wider aperture telescope/camera better quality objective lens use longer exposure time while telescope is locked onto star move telescope to better seeing conditions, e.g. dry desert, higher up a mountain, dark skies improvements from photography, e.g. use longer exposure time use a satellite telescope ignore use pc to adjust the sharpness of the image (2)

51 4(a)(i) D 4(a)(ii) moons must be in correct order heliocentric (2) 4(a)(iii) A description including two of the following points Reflecting telescope has mirror(s) Galilean telescope has only lenses Reflecting telescope can gather more light / can have a larger objective Image viewed from the side of reflecting telescope Image viewed from end of Galilean telescope. refracting telescope reverse argument (2) 4(b)(i) 5 (cm) + - (2) 8 (cm) 0.08 m 80 mm 4(b)(ii) B