ASTR 201 Assignment 1Due 2.30pm (in class) Tuesday 24st September

1. Given that the velocity of light is 3 x108 m/s , define a light-second, a light-hour and a light-year in metres. Express your answer scientic notation. How long does it take light to travel from the surface of the Sun to the Earth? Show your work (5 marks).

2. Short answer questions. Each question is worth 5 marks. Answers to each question should be no more that 150 words.

(a) How do Terrestrial planets differ from Jovian planets in our Solar System?

(b) Why might life in the Universe be common?

(c) What is the difference between an hypothesis and a theory in science? Given an example.