While observing the Halley-type comet 12P/Pons-Brooks with ALMA and NASA's Infrared Telescope Facility, researchers determined that the comet's water is strikingly similar to the water on Earth.

'Devil Comet' contains 'strongest evidence yet' that comets delivered water to Earth

Source: space
Source Link: https://www.space.com/astronomy/comets/devil-comet-contains-strongest-evidence-yet-that-comets-delivered-water-to-earth