The most common noble gas in the universe (and therefore on the periodic table) is helium (He).

Here's why:

* Abundance: Helium is the second most abundant element in the universe after hydrogen. It's formed during nuclear fusion in stars.

* Rarity on Earth: While helium is common in the cosmos, it's less abundant on Earth because it's so light that it escapes our atmosphere.

Let me know if you'd like to know more about noble gases!