Earth's atmosphere originated from outer space, new study finds

Scientists from the University of Manchester and the University of Houston have conducted a study that shows gases from the atmosphere to have come from outer space.

The Earth's atmosphere and its oceans were though to have come from inside the planet, but the study, reported in the journal Science, claims otherwise. According to the team of scientists, the thought that the early atmosphere originated from volcanoes is not correct.

By testing volcanic gases using world-leading analytical techniques, the scientists uncovered this new evidence. They found a clear meteorite signature in the volcanic gases, said Dr Greg Holland, the lead scientist of the project.

This finding indicates that volcanic gases could not have significantly contributed to the Earth's atmosphere. The oceans and atmosphere had to come from somewhere else, Dr Holland added, possibly from comet-like materials rich in gas and water that bombarded Earth.

This is the first time that anyone has been able to use instruments that are capable of finding such subtle sample signatures inside the Earth. The team could measure trace gases from volcanoes such as Krypton and Xenon, which are unreactive. These gases showed isotopic features that matched those in meteorites and that were different that that of 'solar' gases.

Dr Martin Cassidy and Professor Chris Ballentine are also in the discovering team. Prof Ballentine, from the University of Manchester and the project director, said: "Many people have seen artist's impressions of the primordial Earth with huge volcanoes in the background spewing gas to form the atmosphere. We will now have to redraw this picture."