Astronomers have discovered a reservoir of water vapor 12 billion light-years away, containing 140 trillion times more water than all of Earth’s oceans combined, surrounding a quasar that releases as much energy as a thousand trillion suns.

In July 2011, NASA’s Jet Propulsion Laboratory announced that two teams of astronomers had discovered a massive reservoir of water vapor around the quasar APM 08279+5255. The agency translated the typical mass into a number that continues to be repeated: roughly 140 trillion times all the water in Earth’s oceans.

The same story said that the quasar released energy equivalent to a thousand trillion suns. Both comparisons are based on published observations, but neither is as straightforward as it seems. The “reservoir” is gas spread across hundreds of light-years, not a liquid ocean, while the quasar is magnified by forward gravitational lensing.

This is also a 2011 result, and not a new discovery. Her interest now lies in what measurements actually proved about water in the young universe, and how a handful of spectral lines became one of the biggest comparisons of water in astronomy.

The notes were fingerprints in the radio light

APM 08279+5255 has a redshift of 3.91. Light has traveled from the system for about 12 billion years, so astronomers see it as it was when the universe was only about 1.6 billion years old.

Matt Bradford of NASA’s Jet Propulsion Laboratory led one of the teams. In a paper published in Astrophysical Journal LettersAs reported by Bradford and colleagues Six rotational transitions of water were observed using Z-Spec At the Caltech Submillimeter Observatory in Hawaii. Their monitoring program covered 13 nights between 2008 and 2009, for a total of 25.3 hours, and one transmission was examined using the CARMA radio array in California.

A separate group led by Darius Lees used the interferometer at the Plateau de Bure in France. that it Independent detection of excited water transmission It reached the same red shift. That paper also gave a caveat regarding the giant cluster claim: a single radioactively excited line does not provide a good measure of water abundance on its own.

The telescopes did not photograph a swimming pool or weigh the water directly. They measured the radiation emitted at specific frequencies when water molecules change rotational energy states.

The number 140 trillion is a typical inventory

The Bradford team had several water lines in addition to carbon monoxide lines, allowing for a broader model of the molecular gas. The authors compared the spectrum with the much closer ultra-luminous galaxy, Mrk 231, and estimated an average water abundance of about 1.4 water molecules per 10 million hydrogen molecules.

This sounds sparse because it is. The total becomes enormous only because the region contains an extraordinary amount of molecular gas. The combination of abundance and this gas reservoir resulted in the equivalent of 140 trillion Earth’s oceans, or roughly 100,000 times the mass of the Sun in water vapor.

Original JPL ad He described the gas as extending hundreds of light-years around the central black hole. It had a temperature of about minus 53 degrees Celsius, and its density was much lower than Earth’s atmosphere, although it was warmer and denser than the molecular gas typical of the Milky Way.

Thus the perimeter conversion is a communication device of volume, not a tank measurement. This depends on the adopted water abundance, the total molecular gas mass, the excitation model and the gravitational lensing correction.

A black hole is not what shines

A quasar is the luminous center of a galaxy whose supermassive black hole is actively feeding. The black hole itself does not emit any light. Matter in the surrounding accretion flow becomes extremely hot as it loses energy and moves inward, producing radiation across much of the electromagnetic spectrum.

JPL’s description of 2011 APM 08279+5255 has a black hole mass equivalent to 20 billion suns and a luminosity equivalent to a thousand trillion suns. This is a comparison of energy output, not a statement that the object contains that many stars.

The water helped show what this radiation is doing to the surrounding galaxy. Bradford’s paper modeled a region about 550 parsecs in size, or roughly 1,800 light-years. The X-rays heated the molecular gas, while the intense far-infrared glow from the dust pumped water molecules into higher energy states. Their subsequent transitions created the lines detected by telescopes.

In my reading, this is the most useful scientific finding. Water was not only present; It served as a probe of the radiation field, density and temperature around an active black hole in the early universe.

Gravitational lensing holds every giant figure

APM 08279+5255 appears as multiple images because the foreground galaxy bends and amplifies its light. This is gravitational lensing, the same broad effect used by astronomers Time delay measurements of cosmic expansion.

For this source, the magnification factor is discussed. Early work considered the amplification to be around 40 or more. The Bradford team adopted a later model with a magnification of about four. Lower magnification means that the quasar must be substantially brighter and more massive to produce the observed signal.

The estimate of a thousand trillion suns fits within this lower magnification image. It should still be treated as model dependent because changing the lens geometry changes the inferred intrinsic luminosity. Water mass and physical dimensions inherit associated uncertainty.

Lenses do not create false spectral lines. It amplifies the light already emitted. The safe conclusion is that water vapor was present at a redshift of 3.91; The lens model determines how the observed flux is translated into intrinsic mass and luminance.

“Twelve billion light-years away” is short for light travel

For nearby objects, the distance in light years and the time it takes light to arrive are roughly interchangeable. At redshift 3.91, cosmic expansion makes language less ordered. Quasar light has been traveling for about 12 billion years, which is why NASA used “more than 12 billion light-years.”

The galaxy is now more than 12 billion light-years away in current distance convention because space expanded as the light traveled. Astronomers use several distance definitions for cosmic objects, each of which fits different calculations.

The monitoring statement is not based on the selection of a single popular language space. The measured redshift places the emission at a period when the universe was a fraction of its current age.

The discovery was about circumstances, not just quantity

Astronomers have already predicted the presence of water in the distant universe. Previous generations of stars have made oxygen, and ordinary chemistry can combine it with hydrogen. What the team has not measured before at this distance is the spectrum of water that reveals this warm, dense, highly irradiated molecular gas.

A related 2011 study led by Paul van der Werff revealed Four water lines in the same lensed quasar host. Likewise, her excitation model found that intense infrared radiation dominated the higher-energy transitions, and pointed to a mysterious nuclear region where stars form.

More lines and sharper lens patterns can improve stock. The confirmed result is narrower than the headline numbers but scientifically solid: Water vapor was already abundant enough to trace the physical environment around a supermassive black hole when the universe was about 1.6 billion years old.