Flight Sydney Airport departs from Sydney Sydney Airport at 07:00 and arrives at Melbourne Melbourne Airport at 08:35.
The flighttime is about 1h 35m. The distance travelled ("as the bird flies"): 787 Km. So the average speed is roughly 497 Km.
The best day to arrive at Sydney is Tuesday and it would be best to avoid Saturday, as prices are on average 126.09% higher than on Tuesday. (Average prices, based on 36694744 datapoints.)
We have a lot more statistics for flights ZL9 and between Sydney and Melbourne.