Reservoir of Water in Deep Space

​Astronomers have discovered the largest known reservoir of water vapour in deep space, surrounding the quasar APM 08279+5255. This massive cloud, located 12 billion light-years away, contains about 140 trillion times more water than all of Earth’s oceans combined. The finding dates back to 2011, led by Caltech astronomers using telescopes like the Z-Spec at Caltech Submillimeter Observatory and the Combined Array for Research in Millimeter-wave Astronomy (CARMA). 
 
The two teams: one led by Matt Bradford using the Z-Spec instrument at Caltech’s Submillimeter Observatory in Hawaii, and another led by Dariusz Lis with the Plateau de Bure Interferometer in the French Alps. Lis’ team serendipitously spotted a single water spectral signature in 2010 while observing the quasar. Bradford’s group then detected multiple water emission lines, enabling precise mass calculations. These observations leveraged the quasar’s high redshift (z=3.91), shifting water’s rotational transitions into detectable submillimeter wavelengths. Follow-up used CARMA to map the cloud’s extent across hundreds of light-years. 
 
The quasar powers a supermassive black hole 20 billion times the Sun’s mass, heating gases to form the vapor across hundreds of light-years at around -63°F (-53°C).  This water existed just 1.6 billion years after the Big Bang, showing water’s early prevalence in the universe. The cloud holds 4,000 times more water vapour than the Milky Way, though much of our galaxy’s water is ice-bound.  It highlights water’s role in early galaxy formation and complex molecule presence near black holes.  
 
References
Space.Com Staff. (2011, July 23). Astronomers Find Largest, Oldest Mass of Water in Universe. SPACE:COM.
 
Woo, M. (2011, July 22). Caltech-Led Astronomers Discover the Largest and the Most Distant Reservoir of Water Yet. Caltech.