The Child of Helios is a space encounter in NMS. It’s a massive jellyfish-like creature and you first encounter it while on the Starbirth mission.
You can also occasionally encounter it later again in different star systems but you won’t be able to get anything other than it’s request to communicate with you and transmit ‘feelings of pure emotion’. 🙂
If you’re on the Starbirth mission, the creature will give you living water to complete the mission. You can’t aggro or damage it, but it does have collision so watch out if you fly near it.