Astronomers have uncovered an extraordinary water reservoir surrounding a quasar more than 12 billion light-years away, representing the farthest and largest known source of water in the universe. The light from this quasar, named APM 08279+5255, began its journey not long after the universe’s formation, providing a window into the cosmos’ earliest days.
This vast water supply contains about 140 trillion times the amount of water found in Earth’s oceans. It exists near a supermassive black hole at the quasar’s center, which is approximately 20 billion times the mass of the sun. The quasar radiates energy equivalent to a thousand trillion suns, creating an extraordinary environment where molecules, including water vapor, thrive.
“The environment around this quasar is very unique in that it’s producing this huge mass of water,” said Matt Bradford, a scientist at NASA’s Jet Propulsion Laboratory and leader of one of the research teams. “It’s another demonstration that water is pervasive throughout the universe, even at the very earliest times.”
The black hole at the centre of APM 08279+5255 draws surrounding gas and dust inward, heating it up and forming a dense and warm region filled with molecules. The temperature in this region is about -63°F, and the gas density is 300 trillion times lower than Earth’s atmosphere, yet it is significantly hotter and denser than the interstellar medium in most galaxies.
Quasars, among the most luminous and energetic phenomena in the universe, were first observed over half a century ago. They are powered by supermassive black holes, whose accreting gas and dust emit intense radiation across various wavelengths. Observing quasars helps astronomers reconstruct the universe’s early history, revealing how galaxies formed and evolved, how matter dispersed, and how cosmic structures took shape.
The water vapour in this quasar spans hundreds of light-years, suggesting that its environment is bathed in radiation that keeps the gas relatively warm. Alongside water, astronomers detected carbon monoxide, indicating an abundance of raw material capable of fueling the black hole’s growth or forming new stars. Scientists estimate that the black hole could grow six times its current size if all the available gas were to feed it.
This discovery, achieved through years of observations by multiple teams, underscores the importance of water in cosmic evolution. Bradford’s team began data collection in 2008 using the Z-Spec instrument at the California Institute of Technology’s Submillimetre Observatory in Hawaii. Additional confirmations came from the Combined Array for Research in Millimetre-Wave Astronomy (CARMA) in California and a separate team led by Dariusz Lis of Caltech, which used the Plateau de Bure Interferometer in the French Alps.
The findings expand our understanding of the role water plays in the cosmos. Water is not only essential for life as we know it but also critical in cooling gas clouds, enabling them to collapse and form stars. Its presence in such a distant quasar demonstrates that the building blocks of life and galaxy formation existed when the universe was still young.
This extraordinary water reservoir offers insights into how galaxies evolved, how black holes grew, and how molecules like water influenced the cosmos’ earliest structures. By studying such distant phenomena, scientists continue to unravel the vast, intricate story of the universe.
