Sentences with phrase «deuterium ratios»

The temperature record is inferred from hydrogen / deuterium ratios in the ice itself.

Researchers used a multicollector ion microprobe to study hydrogen - deuterium ratios in lunar rock and on Earth.

Moon samples had the same hydrogen - deuterium ratio as found in asteroids and Earth's oceans.

This is the case for the hydrogen / deuterium ratio.

The Vostok or EPICA ice cores deep in Antarctica use the deuterium ratio's because those will resolve at that distance since so little heavy oxygen makes it that far.

Not exact matches

However, the Rosina mass spectrometer aboard Rosetta found that the ratio of deuterium to hydrogen in the comet is far greater than that found on Earth, adding to the growing body of evidence that the water on Earth was delivered not by comets, as previously thought, but by asteroids.

Next, Agee and his colleagues used a laser to extract water molecules trapped within minerals in the meteorite and fed them into a mass spectrometer to calculate the ratio of deuterium, a heavy isotope of hydrogen, to ordinary hydrogen.

To determine the ratios that would currently be found deep in the moon's interior, Van Orman and Saal modeled the loss of gasses from inside melt inclusions and the influence of degassing on the deuterium.

The investigators found that the deuterium / hydrogen ratio in the melt inclusions was relatively low and matched the ratio found in carbonaceous chondrites.

Because comets formed so far from the sun, they tend to have high deuterium / hydrogen ratios — much higher ratios than in the moon's interior, where the samples in this study originated.

The discovery's telltale sign is found in the ratio of an isotopic form of hydrogen, called deuterium, to standard hydrogen.

But when Curiosity's Sample Analysis at Mars experiment (SAM) vaporised Martian soil, it found a ratio five times higher: one deuterium for every 1284 hydrogens.

Brown University's Alberto Saal and colleagues measured the ratio of hydrogen to deuterium (hydrogen with an extra neutron) in lunar rock samples from the Apollo missions.

And ROSINA, a Rosetta instrument that uses spectrometers to measure gas abundances, has obtained a highly sought after result: the so - called deuterium - to - hydrogen ratio of water in the comet's thin atmosphere, or coma.

So, if large amounts of water had disappeared from Venus over the years, there should be a larger ratio of deuterium to regular water left behind.

Although many scientists believe that Venus may once have had oceans of water on its surface (in part because its ratio of deuterium to ordinary hydrogen is now measured to be around 150 times that of the Earth's), most of it has been lost the past five billion years.

Finally, Webb will look at ratios of heavy water — water molecules that contain a deuterium atom instead of hydrogen — to water in the planet - forming disks, helping trace how the water formed and under what conditions.

«The D / H [deuterium - to - hydrogen] value [for water locked in Martian clays] is 3.0 (± 0.2) times the ratio in standard mean ocean water.»

D / H is the ratio of heavy hydrogen (also called deuterium, or D) to normal hydrogen (H).

By measuring the ratio of «normal» hydrogen to the heavier deuterium, Dr Robert Mulvaney and his team were able to make a detailed reconstruction of temperatures spanning the last 15,000 years.

The 8 ppmv/degr.C comes from ice cores, where the ratio between a temperature proxy (deuterium against hydogen or 18O / 16O) and CO2 level is quite linear over 800,000 years.

The problem with your analysis is that the ice cores already reflect the ocean temperature by measuring the ratio of Deuterium to Hydrogen based on the difference in the relative evaporation of each, vs. temperature.

The light oxygen with the deuterium can make it that far though and those ratios can be used instead of oxygen.

«[Siegenthaler et al. (2005)-RSB- analyzed CO2 and proxy temperature (äD, the ratio of deuterium to hydrogen) data derived from an ice core in Antarctica.