Answer Happy

A new type of object, called a Quercusar, has been discovered. The Quercusar appears to be a bright explosion that generates a bright pulse of light with a regular period. Observations of these type of objects in nearby galaxies suggest that the brightness of the object and the flickering period of the object are related. At the same distance, if Quercusar A is 0.7 times as bright as Quercusar B, then it flickers 1.1 times as quickly. a) Can these new objects be used as 'standard candles' to determine cosmological distances? Describe what properties of the Quercusar you are using to make your decision, and describe how standard candles are used to determine distances in astronomy. [4 marks) b) Is there a limit to the distances we can probe using these standard candles? Justify your answer [2 marks]
c) Name two other methods we have to measure cosmological distances in the Universe. How are they limited in terms of the distances they can probe? [4 marks]