Questions on the Earth in Space

Q11.

Until 1781 scientists thought there were only six planets in the solar system. Then a scientist called Herschel looked through a very large telescope that could turn to follow objects in space. He watched a bright object in the night sky for a few months and made drawings of what he saw. He concluded it was a planet.

(a) What method did Herschel use to discover the new planet?

A: He carried out practical tests in the laboratory.

B: He asked scientists' opinions.

C: He observed the environment.

D: He gathered data from books.

1 mark

(b) Scientists today use satellites as well as telescopes to observe the universe. Suggest one way that developments in equipment have changed the information scientists collect about planets.

any one from

  • data from further away can be collected.
  • data from fainter objects or smaller details can be collected.
  • data is clearer because there is no distortion of the Earth's atmosphere (accept 'telescopes can be sited outside atmospheric).
  • more information is collected
  • more detailed or more accurate information
  • wider spectrum of information including photographs or pictures of planet
  • other types of radiation can be detected (microwave, infra red, ultraviolet, X-ray, gamma ray) that gives even more information than the visible light

1 mark

(c) Before 1781, scientists believed there were 6 planets in our solar system. Now scientists believe there are 8 planets. What do these ideas suggest about our knowledge of our solar system?

any one from

  • our knowledge is increasing
  • our knowledge is changing
  • accept 'we probably do not know everything about the solar system'

1 mark

(d) What causes scientists to reject an idea and replace it with a new one?

any one from

  • New evidence from observations or experiments may be collected that challenge accepted ideas
  • There might be a new way of thinking about how the facts fit together - a new interpretation of evidence
  • Old ideas do not explain a new observation

1 mark

maximum 4 marks