(A) Paper 2 wrong pt 2 mocks Flashcards
Some of the meteorites that have been discovered on the Earth are thought to
have originated from the planet Mars.
Describe how material from Mars could become a meteorite on Earth.
- a large asteroid/astronomical object collided with/struck the surface of Mars early in the life of the Solar System (1)
- with a force that was large enough for some (small) rocks to escape from Mars’ gravitational pull (1)
- the Earth passed through the debris and some of the rocks fell to Earth/survived their journey through our atmosphere to land on
Earth (1)
Some astronomers have proposed that there may be life on Titan, because it has an atmosphere.
State two other features of Titan that would be necessary to support life.
- Liquids present (1)
- Internal source of heat/energy (1)
- Suitable temperature range (1)
Explain why the sunspots appear dark on the Sun’s surface.
- they radiate less than the surrounding area (1)
- as they are relatively cooler regions (1)
- because sunspots are areas of strong magnetic fields (1),
- which reduce convection from gases in the Sun (1)
Explain what can be deduced about the relative ages of maria and the
highlands on the near side of the Moon
- Seas/maria have fewer craters (1), which means that they are younger (1)
- Highlands have more craters (1), which means that they are older
Suggest an explanation for lack of maria on the far side of the Moon
- The main reason for lack of maria on the far side is due to Earth’s tidal influence on the Moon early in its life (1).
- This resulted in the near side having a thinner crust and therefore more volcanic eruptions leading to the formation of the maria/the far side’s thicker crust prevented or reduced volcanic eruptions which resulted in no maria forming (1).
Explain why the observed physical properties of red giants require them to have a large surface area.
Red Giants are very luminous but cool stars (1) even though cool stars are usually dim (1), which means the surface area has to be large enough to compensate for its relatively low temperature (1)
Explain two reasons why the Big Bang Theory has overtaken the Steady State Theory as the accepted theory.
- The evidence of Cosmic Microwave Background Radiation (CMBR) shows that there is background radiation in all directions which suggests that ‘a single event’ created the Universe
- Hubble Deep Field image and quasar distribution show that the oldest stars observed are 13.8 billion years old
- however the Steady State Theory predicted older stars would exist (1)
- Theoretical models of the Big Bang Theory predict that hydrogen and helium were produced in the ration 3:1 (1). Observations are in good agreement with this prediction
Give three advantages of connecting radio telescopes together as an array.
- It can detect weaker sources (of radio waves)
- It gives a higher resolution/amount of detail, due to larger baseline (1)
- It enables greater collaboration between astronomers
State two reasons why there are no future plans to send a manned mission to Venus.
- Very high surface temperature
- Very high atmospheric pressure
- Very long day/night
- No chance of water
What are the advantages of a lander
- Can take samples of the water/surface (1)
- and test for the presence of life
- Higher resolution images (closer)
What are the disadvantages of a lander
- Could contaminate the environment (with bacteria etc. from Earth) (1)
- More difficult to land softly on the surface
- More expensive to land softly on the surface
The energy requirements for sending a space probe to Europa or Enceladus are
much greater than those required to orbit the Earth. State a reason for this.
Must reach escape velocity
It is possible for water to exist as a liquid below the surface of Enceladus and Europa. Explain this statement
The moons generate internal heat (1)
from tidal gravitational forces (1)
Liquid water is not thought to exist in the nucleus of the comet 67P. Explain this statement
- Comet does not generate internal heat
- does not experience tidal forces (1)
- because it does not orbit close to a gas giant planet (1)
- Comet has no atmosphere (1)
Describe the observational evidence that the Milky Way galaxy is classified as spiral rather than elliptical.
- More stars observed in a band (Milky Way) across the night sky.
- Indicating a flat spiral shape – looking down the plane of this spiral.
- Elliptical galaxies stars more uniformly distributed. (1)
- If our galaxy were elliptical we would not observe a band of stars/ Milky Way running across the night sky. (1)
Name one method other than using magnitudes of stars that astronomers use to measure stellar distances.
(Heliocentric) Parallax (1)
or
Use of HR Diagram (1)
Explain how to find stellar distances using the heliocentric parallax
- Measure the change in position of a star (astrometry) (1)
- after a long (6 month) period of time as Earth orbits the
Sun (1)
Explain how to find stellar distances using the HR diagram
- Measure surface temperature of a star (spectral type) (1)
- determine its absolute magnitude (and distance) from the HR diagram (1)
