The "night sky" itself isn't something that was "created" in a specific moment. It's a product of several natural phenomena that have been in place since the very beginning of the universe:

* The Universe: The Big Bang occurred approximately 13.8 billion years ago, creating the universe and all its matter.

* Stars and Galaxies: Stars began to form within the first few hundred million years after the Big Bang, eventually grouping together to form galaxies.

* Planets and Solar Systems: Our solar system, including Earth, formed around 4.5 billion years ago.

* Earth's Rotation: Earth spins on its axis, causing day and night, making the night sky visible.

So, while we don't have a specific "creation date" for the night sky, we can say it's been around for at least 4.5 billion years, and is constantly evolving as the universe expands and stars continue to form and die.