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Astronomy GCSE
Exam revision
Question | Answer |
---|---|
The planet Uranus was discovered by | William Herschel |
A star that regularly changes it brightness is called a | Variable star |
The region around a star where planets may be able to support life is called | The Goldilocks zone |
The sun crosses the celestial equator on the | 21st March |
Do exoplanets orbit the sun? | No |
What does the aurora borealis appear as to the naked eye? | A colourful band or curtain of light across the sky. |
What does an artificial satellite appear like to the naked eye? | A point of light moving quickly across the sky. |
What does a a fireball appear like in the night sky. | A fast moving bright streak of light. |
What does a start with an apparent magnitude of +5 appear like to the naked eye? | A very faint object. |
Which planet orbits the sun in the shortest time? | Mercury |
Which gas giant orbits nearest to Kuiper's belt? | Neptune |
Which planet passes closest to Earth? | Venus |
Which is the largest inferior planet? | Venus |
Which feature on the moon? A long narrow channel. | Rille |
Which feature on the moon? A Highland area. | Terra |
Which feature on the moon? A smooth dark plane. | Mare |
Describe two differences in the dark side of the moon. | More craters, more mountains. |
What is the approximate temperature of a typical sunspot in Kelvin? | 5K |
Describe a method for using a telescope to view sunspots safely. | Projection |
Which object in the Solar System out of the Earth, Jupiter the Moon and the Sun has the smallest diameter? | The Moon |
Which object in the Solar System out of the Earth, Mars, Mercury and the Moon is closest to the Sun? | Mercury |
Which object in the Solar System out of the Earth, Neptune, Pluto and Venus takes the longest to orbit the Sun? | Pluto |
What is the name of the dwarf planet that orbits closest to the Sun. | Ceres |
What is the value of 1 AU? | 15,000.000 km |
What is the name of the Earths orbit around the Sun? | Ellipse |
What is the name plane of the Earth's orbit around the sun? | Ecliptic |
How many hours and minutes does it rake the Earth to rotate on its axis once? | 23 hours and 56 minutes |
How long does it take the moon to spin on its axis once? | 27.3 days |
What is the phase of the Moon during a lunar eclipse? | Full moon |
Name two planets that have ring systems? | Neptune and Jupiter, Saturn |
Which planet has two small satellites that astronomers believe are captured asteroids? | Mars |
The atmosphere of Venus can be used to demonstrate the danger of extreme global warming on Earth. | Extremely high temperatures. High Concentration Co2 |
A student is observing Polarus, which direction would they be looking? | North |
State the declination of Polaris. | 90 degrees |
What is the angle of elevation of Polaris if the student is observing from 55 degrees N? | 55 degrees |
What are circumpolar stars? | Stars that do not set from Earths Vantage point. |
Would a star that is +60 degrees be circumpolar from 55 degrees latitude? | No because this star would move out of view at certain times. |
Describe the appearance of sunspots. | Dark patches on the suns surface, |
Name a suns feature that an Astronomer might observe. | Solar flares |
Does a H-filter improve the astronomer's observations of sunspots? | The filter provides a better contrast. |
How do Astronomers use sunspots to determine the Sun's rotation period? | Galileo concluded that the Earths rotation carries the sunspots around. Observing the sunspots enables the observer to calculate the suns rotation period. |
Describe the appearance of aurorae. | It is a glowing coloured curtain of lights in the sky. |
Explain the connection between aurorae and solar winds. | Charged particles in the solar wind excites and interacts with gas molecules in the atmosphere. |
Where is the origin of most short-period comets? | Kuiper's Belt |
What is the name of the point from which meteors diverge? | radiant of the shower |
In which constellation does the point for this meteor occur? | Persius |
What is the difference between a meteor and a fireball? | A fire ball is exceptionally large and bright whereas a large meteoroid has a magnitude of _3. |
What is the approximate diameter of our galaxy? | 30 KPC |
Describe two meths Astronomers use to detect the presence of exoplanets. | 1. Astronomers look for small wobbles in the position of a star. 2. Look for radial velocity meths - doppler shifts in stars. |
Explain why Astronomers find it difficult to detect individual planets. | The star is much brighter than the planet or there may be dust disk or gas around the planet. |
Name the Space mission that visited Mars on the 20th July 1976. | Viking Lander 1 |
State two problems that Astronauts are likely to face during a manned expedition. | 1. Brittle bones 2. Communication time delay. |
State the difference between a binary star and an optical double star. | A binary star is physically close and gravitationally associated. An optical double star is in line of site but only appears close together, |
Name one major source of light pollution. | Street lights |
Which Greek Geographer and Mathematician calculated the circumference of the Earth. | Eratosthenes |
Which two cities did Eratosthenes use to calculate the circumference of the Earth. | Alexandria and Syene |
Which city that Eratosthenes used to calculate the e circumference of the Earth is on the Tropic of Cancer? | Syene |
What day did Eratosthenes measure the position of the sun to look at the different shadows when calculating the e circumference of the Earth. | Summer Solstice. |
What was the angle of the shadow between Syene and Alexandria? | Measured angle of the shadow. -7.2 degrees 1/50 circle |
Define Longitude | The angular distance of a place east or west of the Greenwich meridian usually expressed in degrees and minutes. |
Define latitude | The angular distance of a place north or south of the earth's equator usually expressed in degrees and minutes. |
Define the electromagnetic spectrum | The electromagnetic spectrum is a continuous range of wavelengths. The types of radiation that occur in different parts of the spectrum have different uses and dangers, which depend on their wavelength and frequency. |
Name the electromagnetic spectrum in order of wave lengths | Gamma Rays, X rays, Ultraviolet rays, Visible light, Infrared, Microwaves, Radio waves |
Why do astronomers use 21cm radio waves rather than visible light to determine the rotation of our galaxy? | Radio waves will penetrate dust in spiral arms. Visible light is unable to penetrate dust. |
Give three facts about Cosmic Microwave Background radiation. | 1..In 1965 discovered by Penzias and Wilson. 2.Echo of a big bang. 3. Corresponds to 3 K temperature. |
Describe how astronomers use the Hubble Constant to determine the age of the Universe. | Hubble discovered the further away a galaxy is, the faster it is receding. You convert the value of H into inverse of time units. |
Give two facts about active galaxies. | 1. A lot of strong X ray emissions. 2. Active black hole at centre. |
Define Quasars. | Quasars are distant galaxies with high redshift. |
Describe briefly how Quasars were discovered. | They gave out a strong radio source and were matched to faint star like objects observed by optical astronomers. |
Which planet is known to support life? | Earth |
Which planet is a god giant with a prominent ring system? | Saturn |
Which is the Earths's 'twin' planet with a dense atmosphere of Co2? | Venus |
A heavily crated planet that closely resembles the moon. | Mercury |
Which rocket was used to launch the Apollo 11 spacecraft into an orbit around the Earth before it went to the Moon. | Saturn V |
What is the difference between a rocket and a spacecraft? | A rocket is a launch vehicle which is powered whereas a spacecraft continues to orbit and is unpowered. |
What was the main purpose of the Apollo space programme? | To send humans to the moon and to collect samples and return them safely back again. |
Why up until now have humans been confined to the immediate vicinity of Earth in terms of space exploration. | It has been difficult to provide enough fuel and food for a longer journey. There are greater health risks in terms of bone density. |
Which constellation contains three stars that point to Sirius? | Orion |
Which constellation contains two stars that point to Polaris? | Ursa Major |
Name four properties of light and all other forms of electromagnetic radiation. | 1. Interference 2. Reflection 3. Refraction 4. Scattering |
Which properties of light is responsible for the Earth's blue sky during the day? | Scattering |
Which properties of light causes the starts to appear higher in the sky than the should? | Refraction |
Which properties of light allows the radar technique to determine distances to nearby objects? | Reflection |
Which properties of light makes the planets' visible? | Reflection |
What are sunspots? | Cooler darker regions associated with localised magnetic fields. |
State the approximate call in years for the solar cycle. | 11 years |
During one solar cycle state how the sunspots change. | The number of sunspots increase and decrease. |
During one solar cycle state how the latitude of most sunspots change. | They drift to lower latitudes. |
Mant astronomers believe that Mars's two moons are captured asteroids. Give to reasons why this might be so. | They are similar in their irregular shape and surface features to asteroids. |
In which two planets are the most asteroids located? | Mars and Jupiter |
Describes how asteroids have been formed. | The splitting of a large rock. |
Give two reasons why most asteroids are not bright enough to be seen with the naked eye. | 1. They are too far away 2. There is too much light pollution. |
Name the parts of a comet. | Nucleus, Coma and a tail. |
What causes a Comet's dust tail to be visible? | Reflecting sunlight. |
Why does a Comet's dust tail point away from the sun? | Radiation, pressure from the sun. |
hat causes a Comet's ion to be visible? | Sometimes, the gas tail disappears and later reappears when the comet crosses a boundary where direction of the sun's magnetic field is reversed. |
Which of a Comet's tail appears straight? | Ion tail |
What is meant by a sidereal day? | The time taken for the Earth to spin. |
How long is a sidereal day on the Earth? | 23 hours and 56 minutes |
An astronomer observes Polaris from a latitude of 57 degrees N. The declination of Polaris is +90 degrees. What is the angular distance of Polaris above the northern horizon? | 58 degrees |
What is the solar wind? | Streams of charged particles ejected at high speed from the sun. |
Which part of the sun has the highest temperature? | Core |
What are aurorae? | Glowing curtains of light moving across the sky. |
Which part of the Earth can aurorae? | Arctic and Antarctic |
A planetary nebula represents the final stages of a star with a mass approximately equal to that of the Sun.Briefly describe the final stages of a star that has a much greater mass. | The star explodes and ejects material into space. The core contracts, implodes and forms a black hole. |
Describe the observational evidence of black holes. | Studying the speed of gas clouds, The hubble Space telescope measured the mass of an unseen object at the centre of M7. Object estimated to be 3 billion times the mass of the Sun concentrated into a small hole. |
Outline the discovery of Neptune. | Planet predicted by wobbles in Uranus by Vernier. Searched successfully by Galle and D'Averst. |
Give 2 astronomical reasons why Pluto should be regarded as a planet. | 1. Spherical in shape. 2. Has moons. |
Give 2 astronomical reasons why Pluto should not be regarded as a planet. | 1. Too small to be seen as a planet. 2. Has not cleared its orbit. |
Describe how the Lovell Telescope extracts information that can be used from the incident waves. | The dish collects radio waves, the ariel converts the radio energy into electric signals which is processed later. |
The first Quasar was discovered by astronomers using a radio telescope. Give two key facts about Quasars. | 1. They have high redshift. 2. They are early galaxies and give off non thermal radiation. |
Describe the evidence astronomers give for the big bang. | The red shift of distant galaxies suggests the universe is expanding. The evidence for cosmic microwave background radiation and the light from distant galaxies that are further away and more redshifted. |
Which astronomer was one of the first to propose a theory of the Solar System where the Sun rather than the Earth was at the centre. | Nicholaus Corpernicus |
What name to astronomers give to any theory that places the Sun at the centre of the Solar System. | Helliocentric theory |
In what other ways did Copernicus' theory improve on earlier theories of the Solar System. | It explained retrograde motion of the planets and enabled motion of the planets to be predicted. |
Corpernicus' theory was further supported by the discoveries of the astronomer Gallileo Galilei. Name two of these discoveries. | 1. Galileo found that Venus went through phases, just like our Moon. But, the nature of these phases could only be explained by Venus going around the Sun, not the Earth. 2. Moons of Jupiter went around Jupiter and not the Earth. |
Name Who invented the telescope? | Galileo |
Which astronomer discovered sunspots? | Galileo |
Name the terrestrial planets. | Mercury, Venus, Earth, Mars, |
Name the planet which orbits the sun in the shortest time. How many days does it take? | Mercury, 88 days |
What does inferior planet mean? | "Inferior planet" is used in reference to Mercury and Venus, which are closer to the Sun than the Earth is |
Superior Planet | Superior planet" is used in reference to Mars, Jupiter, Saturn, (and later additions Uranus and Neptune), which are farther from the Sun than the Earth is. |
Explain what it means we a planet is in transit. | When something passes the Sun. Only Mercury and Venus transition the Sun. |
When is the only time Venus can be seen in transit? | When it is in conjunction. (Objects close together) |
Define elongation | Furthest from the Sun. |
Define opposition | Earth between plant and Sun. |
Define Occultation | An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer |
Why was the first record of a transit of Venus not made until 1693? | Transit was not accurately predicted. |
Why are traits of venus so rare? | Earth and Venus' orbits are very slightly differently inclined. |
Why were the first probes to the moon unmanned? | Because it was not known if it was dangerous to put humans on the moon. |
State the first space mission to land a human safely on the moon. | Apollo11 |
Give one feature of the Moon that means a spacecraft is likely to reach its surface travelling more slowly than on Earth. | The Moon has much less gravitational pull. |
Give one feature of the Moon that means a spacecraft is likely to reach its surface travelling more quickly than the Earth. | The Moon has very little atmosphere to slow down an object falling to the surface. |
Explain why the sky appears black, rather than blue during daytime on the Moon. | The moon has no atmosphere which means that no scattering of light takes place. |
Who discovered Neptune? | Galileo was the first to discover it but thought it was a star. Neptune was supposedly discovered in 1846 by Johann Gottfried Galle using calculations by Urbain Le Verrier and John Couch Adams, making it a joint British-French-German discovery. |