Tag Archive for 'Oxygen-18'

This chart shows the average chemical signatures in the tooth enamel of different animal groups from the Cretaceous period. The vertical axis tracks carbon: the higher an animal’s carbon-13 reading, the more its diet likely came from the sea. The horizontal axis tracks oxygen, which reflects the local water the animals drank, such as a river, lake or seaway. Image credit: Forster et al., doi: 10.3389/fevo.2026.1895247.

Dinosaurs May Have Dined on Seaweed, Study Suggests

Oct 1, 2026 by Enrico de Lazaro

Paleontologists studying Cretaceous fossils have repeatedly found that the teeth of many ancient animals contain more of a heavier carbon isotope, carbon-13,...

Mirror nuclei, such as oxygen-18 and neon-18, have the same number of protons and neutrons (18), but while oxygen-18 has 8 protons and 10 neutrons, neon-18 has 10 protons & 8 neutrons. When they absorb enough energy, they can decay and emit an alpha particle (2 protons and 2 neutrons). Image credit: M. Barbui.

Nuclear Physicists Find Evidence of Superradiance in Mirror Nuclei

Jun 28, 2023 by News Staff

Superradiance occurs when an atomic nucleus reaches a high excitation energy. Mirror nuclei, such as oxygen-18 and neon-18, have the same number of protons...

This schematic shows the layers of Earth’s atmosphere, from the troposphere to the thermosphere. SOFIA observes from within the stratosphere and studied the ratio of main oxygen to heavy oxygen in the mesosphere and lower thermosphere, up to an altitude of about 200 km (124 miles). Image credit: NASA / SOFIA / L. Proudfit.

SOFIA Makes First Detection of Oxygen-18 in Mesosphere and Lower Thermosphere of Earth

Mar 8, 2023 by News Staff

In the lower atmosphere of Earth, oxygen contains a higher fraction of the heavy isotope 18O than ocean water does. This enrichment is a signature of biological...

An artist’s impression of a water-world planet. Image credit: Sci-News.com.

Archean Earth Was Covered by Global Ocean, New Study Suggests

Mar 3, 2020 by News Staff

The surface of Earth was likely covered by a global ocean 3.24 billion years ago (Archean Eon), according to a new study published in the journal Nature...