Flight Tan Son Nhat International Airport departs from Ho Chi Minh City Tan Son Nhat International Airport at 21:15 and arrives at Melbourne Melbourne Airport at 08:35.
The flighttime is about 8h 20m. The distance travelled ("as the bird flies"): 5004 Km. So the average speed is roughly 600 Km.
There is an 3 hour time difference between Ho Chi Minh City and Melbourne