Free Astronomy Magazine May-June 2023

21 MAY-JUNE 2023 ASTRO PUBLISHING T his artist’s impression shows the planet- forming disc around the star V883 Orio- nis. In the outermost part of the disc water is frozen out as ice and therefore can’t be easily detected. An outburst of energy from the star heats the inner disc to a tempera- ture where water is gaseous, enabling astronomers to detect it. The inset image shows the two kinds of water molecules studied in this disc: normal water, with one oxygen atom and two hydrogen atoms, and a heavier version where one hydrogen atom is replaced with deuterium, a heavy isotope of hydrogen. [ESO/L. Calçada]