Hello I've noticed on the last few pets I've encountered in explore that they have stars. I've seen 2 green stars and 2 pale blue stars. Do these mean anything?

The color of the stars on a pet represents the rarity of the pet you're encountering and how many trait points it has.

One thing to note is how trait points work, a carried trait is worth 1 trait point while a visible trait is worth 2 trait points.

Common/Grey Stars: No trait points.

Uncommon/Green Stars: 1 trait point. Can be only 1 carried trait.

Rare/Blue Stars: 2 trait points. Can be either 2 carried traits, or 1 visible.

Epic/Purple Stars: 4 trait points. Can be 2 visible, 4 carried, or 1 visible and 2 carried.

Legendary/Orange/Yellow Stars: 6 trait points. Can be 3 visible, 2 visible and 2 carried, 1 visible and 4 carried, or 6 carried.

Mythical/Red Stars: 8 trait points. Can be 4 visible, 3 visible and 2 carried, or 2 visible and 4 carried.

Outside of the Lost Grove, the only way to trap a Legendary or Mythical Pet in battle is with a Masterful Snare Trap, which can be purchased from the diamond shop, from other users on the trade broker, or earned through Seasonal Festival(Spring, Summer, Fall, and Winter) task of catching 50 themed pets. Masterful Snare Traps immediately catch the pet it's used on.

Any traps from the areas outside of the Lost Grove can fail when attempting to use them to catch a pet. This may lead to multiple traps used or a pet running away from the battle to avoid being caught. I remember reading that the lower you make a pet's health, the higher your chance you have of catching it.

Common pets can be caught with any type of trap.

Uncommon pets need a Lesser Snare Trap at least to catch it. Standard and Strong Snare Traps can be used for them as well.

Rare pets need a Standard Snare Trap at least to catch it. Strong Snare Traps can be used on them as well.

Epic pets need a Strong Snare trap to catch them.

You can use a Masterful Snare Trap on any rarity outside of Legendary and Mythical, but they're rarely worth using on anything below that rarity unless it's a valuable themed pet.

In the Lost Grove, the traps you use are effective based on the pet's health. The higher rarity of the trap, the less health you need lower from the pet to attempt to catch them. Though it can still take multiple attempts to catch the pet.
Also, the higher rarity a pet is in the Lost Grove, the stronger it is.
You can also use Masterful Snare Traps in the Lost Grove.

Sorry for the long post! I wanted to try explaining the best I could. ^^

ah. Thats probably why I couldn't catch the blues. I only had the lesser snares I think. Thank you! I noticed that and was so confused.

Edit: Wait no those are common then. I thought those were pale blue. Never mind ingnore that. But thank you for the information

Edit Edit: Does the number of stars mean anything? Ive seen some commons with 1 and some with 2

If I remember right, the number of stars relates to how strong the pet/enemy is. The more stars, the more likely the enemy is to be strong and have higher health.
Themed pets, encountered in the Lost Grove and Fest Zones, also have a higher amount of stars. ^^

we cover star colour and number here