Water is essential for life as we know it – water makes up around 70% of the human body, covers about 70% of the planet Earth, has been found in the far reaches of our universe, and is at the centre of our search for habitable planets around other stars.
But how does this water find its way from interstellar space to the comets and planets it is found on? This was one of the questions that Professor Michel Fich from the Faculty of Science, and his international colleagues set out to research, using observations from the Herschel Space Observatory.
Measuring infrared light waves from its orbit around the Earth, this telescope had a unique eye on the stars, away from the water vapour in the Earth’s atmosphere. This let the telescope search the infrared wavelengths for signs of water in the far reaches of our universe.
Five years and over 100 academic papers later, this international group of researchers has published a summary and new analysis of their findings in the paper Water in star-forming regions: Physics and chemistry from clouds to disks as probed by Herschel spectroscopy.
“This paper paints the most complete picture ever done of how water is formed in space, and ultimately ends up in planets,” says Fich. “It’s very exciting to see the work of so many people around the world brought together in one place.”
Every molecule has a unique “fingerprint”, known as a spectrum, that can be studied and traced under different wavelengths of light. By identifying, isolating, and measuring the various spectra of water in its different molecular forms and at different temperatures, Fich and the other researchers were able to piece together the movement of water molecules in regions of space where stars and planets are still forming.