Well, crap.
I hit a wallaby shortly after leaving the observatory. It bolted out of the scrub on the right side of the road, I saw it straight away and slammed on the brakes but on wet road there was no way I could stop in time and I had nowhere to swerve either. It died... but not instantly. Horrible. The rental car was damaged, but fortunately still drivable.
The wet gloomy weather was bringing out all the animals that are normally hidden away in the middle of the day. Later I had a near miss with a turtle, and an uncomfortably close encounter with a wombat, all before reaching my first rest stop in Merriwa. The rain continued non-stop all the way to Kurri Kurri, making for a very stressful drive. The usual wet weather driving stuff, plus rampant anxiety about normally crepuscular animals poised to leap out from behind every bush.
This is only the second time I've inadvertently killed an animal with a car. The previous time was also driving back to Sydney from Siding Spring Observatory, also in a rental car, near the M1 end of the Hunter Expressway quite late at night. That was bad, but in a way slightly less distressing as I didn't see the kangaroo after the impact. It got flung away into the darkness and I opted not to go walking down the road to find it while cars were flying past at 110+ kph.
The car on that occasion was hired from the same place. I wonder if they're going to realise that this is the second time I've returned one of their cars with macropod induced damage to the front end? I expect to get a not fun phone call from them when they open up at 8 am tomorrow.