Earth’s water explained by gas giant gluttony 

Posted: July 19, 2017 by oldbrew in Astrophysics, research, solar system dynamics

Niagara Falls [image credit: Saffron Blaze / Wikipedia]

The author of this theory says “Jupiter and Saturn’s growth naturally pollutes the inner Solar System with water-rich planetesimals. In my mind the mechanism is very clear”. The theory does seem to bear a resemblance to this summary from the Hans Rickman Uppsala Astronomical Observatory.

Water on Earth, Mars and everywhere within the inner Solar System can be traced back to the rapid waist-expanding growth of Jupiter and Saturn, which knocked inwards a local population of icy planetesimals, as Sci-News reports.

This is according to a new model, which could also explain the current makeup of our modern asteroid belt.

Whilst Earth is often described as the blue marble, with over 70% of its surface covered in oceans, seas, rivers and lakes, water actually makes up less than 0.1% of our planet by mass.

The majority of H2O in the inner Solar System actually can be found in the asteroid belt — particularly within the outer belt’s carbonaceous asteroids. Meteorites from these so-called C-type asteroids have contained up to 10% water by mass.

However, for scientists, a bigger surprise is the fact that water exists at all this far inside the orbit of Jupiter, where temperatures should have restricted planetary bodies to grow out of little more than rock and iron.

Debates over the origin of this inner solar system water go back decades, focusing initially on icy comets.

However, at the dawn of the 21st century that preference has to be rethought after comparisons of a particular chemical fingerprint of water, known as its D-H ratio, between samples from Earth and those collected from asteroids, comets and free solar system gas showed it was the C-type asteroid water that matched most closely with Earth’s.

“It suggested that C-type asteroids and whatever delivered Earth’s water came from the same population,” says astronomer and solar system modeler Sean Raymond at the Laboratoire d’Astrophysique de Bordeaux in Bordeaux, France.

“They are brothers and sisters from the same parent population.”

Now all that was lacking was an origin of these celestial siblings and an explanation of why they packed up and left their colder outer solar system home.

Continued here.

  1. Roger,

    water actually makes up less than 0.1% of our planet by mass.

    Here is something to think about.

    Water makes up a much larger percent of the crust. The crust and core rotate at different speeds and changes to ice and water volumes influence the spin rate of earth much more because it only influences changes in spin rate of the crust. More ice is close to the spin axis and more water is further from the spin axis. Less leap seconds are added now than in the seventies when we first we started using the atomic clock. Spin rate has increased so there is more ice on land an less water in the oceans.


  2. BoyfromTottenham says:

    I still don’t know where the Earth’s water came from, before the asteroids apparently deposited it on Earth. Any ideas anyone?

  3. oldbrew says:

    Where did any solar system body get its water from? An oxygen source is necessary to put the O in H2O.

  4. dscott says:

    Where from? The sun of course:


    We analyze the physical origin of plasmas that are ejected from the solar corona. To address this issue, we perform a comprehensive analysis of the elemental composition of interplanetary coronal mass ejections (ICMEs) using recently released elemental composition data for Fe, Mg, Si, S, C, N, Ne, and He as compared to O and H. We find that ICMEs exhibit a systematic abundance increase of elements with first ionization potential (FIP) < 10 eV, as well as a significant increase of Ne as compared to quasi-stationary solar wind. ICME plasmas have a stronger FIP effect than slow wind, which indicates either that an FIP process is active during the ICME ejection or that a different type of solar plasma is injected into ICMEs.

    Everyone is so wedded to the cloud disk formation theory that they miss the 800 lbs gorilla in the room…the sun.

    While Jupiter may have shepherded the water ice toward the inner solar system, it came from somewhere. What people miss here is that in order to accept the cloud disk formation theory, you must accept that the matter for the cloud MUST have been free floating in interstellar space before being trapped in the gravitational well of the forming cloud system. So either the Oort Cloud is the rim of that cloud disk that didn’t get pulled closer to the center of the forming system OR the sun ejected the material. This leaves us with an intriguing question, why are there any space borne materials at all orbiting the sun in the inner solar system when there are 4 inner planets to scoop up all the material over time? Isn’t the rational explanation that new material is being introduced?

  5. oldbrew says:

    Oxygen in the Sun

    Andrew M. Davis, Ko Hashizume, Marc Chaussidon, Trevor R. Ireland, Carlos Allende Prieto, David L. Lambert
    DOI: 10.2138/rmg.2008.68.6
    First Published on February 06, 2008

    © The Mineralogical Society Of America

    ‘the Sun contains nearly all (~98%) of the Solar System’s oxygen’

  6. J.S. Pailly says:

    I’m sort of amused by the idea that Jupiter and Saturn “polluted” the inner Solar System with water. That was really inconsiderate of them. 😉

  7. Tim Spence says:

    I thought it was now established that neither Asteroids nor Comets were the source of our water (H2O) because their water (like some of Jupiters moons) is not Hydrogen water but Deuterium or some other isotope. Anyhow, it’s fascinating stuff. And if the first earth atmosphere was mainly CO2 where did the Oxygen come from?

  8. oldbrew says:

    Even if the Earth did get bombarded by water-ice-bearing small bodies, that would still leave the question of where they got their H2O from.

  9. p.g.sharrow says:

    One more lame theory from “educated” savants.

    Look at the facts on the ground! Terrestrial water is boiling out of the earth’s crust, as it has since the creation of the Earth/Luna pair from the remains of a near collision of the gas planet, Mu, and and an errant in the early days of our Solar system. The Sun is slowly blasting the Earth’s atmosphere and water away into the outer reaches of that system. The outer planets are collectors of water, not transporters into the inner solar system…pg