Carnegie Institution researchers claim much of the water in our Solar System likely comes from interstellar space

Sep 26, 2014 07:00 GMT  ·  By
Illustration of water in our Solar System through time from before the Sun's birth through the creation of the planets
   Illustration of water in our Solar System through time from before the Sun's birth through the creation of the planets

Earlier this week, researchers with Carnegie Institution for Science in the US published a paper that will forever change the way you look at a glass of water, a cup of tea and pretty much everything else on this planet.

In their paper, available in the journal Science, these brainiacs argue that, according to their investigations into the matter at hand, it is possible that the water on Earth is much older than the Sun.

In fact, the Carnegie Institution scientists argue that, all things considered, it might be that all the water in the Solar System was once ice in interstellar space, and is therefore way older than we imagine.

The birth of the Sun

In their paper in the journal Science, the researchers explain that, when very young, the Sun was surrounded by a so-called protoplanetary disk, otherwise known as the solar nebula. This disk packed the elements that eventually got together to form planets.

By the looks of it, ice counted itself among the elements that comprised the Sun's protoplanetary disk. Hence, it was incorporated into the planets that came into being around this star.

What puzzled scientists for quite a while was whether the ice in the Sun's protoplanetary disk was the result of reactions taking place in the nebula or if maybe it was leftovers from the interstellar molecular cloud that birthed the Sun.

Simply put: did this ice form around the Sun on its own accord, or did it use to be part and parcel of the Sun's parent interstellar molecular cloud and was left behind when this star formed?

Solving the puzzle

Looking to solve this mystery, researchers turned their attention to hydrogen and deuterium. Now, hydrogen and deuterium might sound like they are two completely different things, but the fact of the matter is that they are one and the same element.

Thus, hydrogen and deuterium have the same number of protons, and only differ in the number of neutrons they carry. In fact, deuterium is sometimes referred to as heavy hydrogen.

Because they have different masses, hydrogen and deuterium behave differently when engaged in chemical reactions. Scientists say that, by studying how much hydrogen there is in water molecules when compared to deuterium, they can figure out how the molecules formed.

Having analyzed several models based on what they already knew about hydrogen and deuterium behavior, the scientists found that the composition of the Earth's oceans, together with that of comets, could only be explained if the Solar System did not form all the water from scratch, and instead inherited at least some from interstellar space.

“Our findings show that a significant fraction of our Solar System’s water, the most-fundamental ingredient to fostering life, is older than the Sun,” researcher Conel Alexander with the Carnegie Institution for Science said in a statement.

Importance of this study

The discovery that at least some of the water in our Solar System actually comes from interstellar space is bound to help scientists better understand which planets might harbor life forms similar to the ones here on Earth.

Thus, this find sheds new light on how environments that encourage the emergence of life come into being, and should make it easier for researchers to figure out where exactly they should go looking for alien life.

“Why this is important? If water in the early Solar System was primarily inherited as ice from interstellar space, then it is likely that similar ices, along with the prebiotic organic matter that they contain, are abundant in most or all protoplanetary disks around forming stars.”

“But if the early Solar System’s water was largely the result of local chemical processing during the Sun’s birth, then it is possible that the abundance of water varies considerably in forming planetary systems, which would obviously have implications for the potential for the emergence of life elsewhere,” explained Conel Alexander.