Illustration of the T Tauri star (TTS) PDS 70 (white) and its surrounding protoplanetary disc (red). A TTS is a class of stars that are less than 10 million years old, relatively young for a star. A protoplanetary disc is a collection of dust, gas, asteroids and other objects which orbit young stars, and the site of eventual planet formation. The James Webb Space Telescope (JWST) discovered water vapour in the inner region of this disk in 2023. The inner region is where rocky, terrestrial planets can form. This is of interest as the Earth is in a similar region relative to the Sun, so this discovery may help us understand how water reached the Earth.