Not Frozen Ice, But Uranus And Neptune May Contain Methane, Claims New Study

In 1980, NASA’s Voyager 2 spacecraft made a big revelation about the two important planets of the solar system, Uranus and Neptune. At that time, based on the information received from Voyager, scientists had concluded that there was a large amount of ice frozen on the two planets. As is usually the case, ice was meant to be frozen water. But, a new study has shown that these planets may also contain substantial amounts of methane ice.

It is being said that this discovery can help in solving the puzzle of how both planets were formed. Uranus and Neptune have been a source of mystery due to their distance from Earth and the limited data available. Astronomers have developed models based on these observations, which suggest that the planets have a thin hydrogen and helium envelope, a buried superionic layer of water and ammonia, and a rocky core, with a water component making them “ice giants”.

The new study challenges this notion by considering the formation of Uranus and Neptune. According to the report, as these planets formed from the primordial dust cloud around the young Sun, they may have swallowed bodies similar to present-day comets, also called planetesimals.

These small celestial bodies are thought to contain high levels of carbon, unlike the presumed water-dominated materials suggested in existing models. “How can we explain the formation of an icy giant using building blocks lacking in ice?” queries Uri Malamud, a planetary scientist at Technion–Israel Institute of Technology and the lead author of the study.

To reconcile this inconsistency, the researchers developed numerous models of Uranus and Neptune’s internal structures, examining different compositions such as iron, water, and methane. They discovered that models incorporating methane, either as solid masses or in a semi-liquid state under immense pressure, most accurately matched the observed characteristics of the planets. The presence of methane may help resolve the paradox of how these ice giants came to be. Scientists propose that methane ice formed when hydrogen in growing planets chemically reacted with carbon, which would have grown in greater quantities in developing planets. Future missions sent to these planets will be able to confirm these results.