About 2 billion years ago, the transition from the volcanic gas atmosphere to the current nitrogen-oxygen atmosphere occurred. The oxygen-carbon dioxide ratio has fluctuated during the past, reaching an oxygen-rich high of about 35 percent during the Carboniferous Period million years ago and an oxygen low of about 15 percent near the end of the Permian Period million years ago.
The modern atmosphere contains about 78 percent nitrogen, 21 percent oxygen, 0. This ratio, with some fluctuations of the oxygen-carbon dioxide ratio, has allowed the development of life on Earth. Conversely, the interactions between photosynthesizing plants and respiring animals maintain the current atmospheric ratio of gases. Karen earned her Bachelor of Science in geology. She worked as a geologist for ten years before returning to school to earn her multiple subject teaching credential.
Karen taught middle school science for over two decades, earning her Master of Arts in Science Education emphasis in geosciences along the way.
Water vapor Carbon dioxide Sulfur dioxide Hydrogen sulfide Carbon monoxide Sulfur Chlorine Nitrogen Nitrogen compounds like ammonia, hydrogen and methane. Climate of the Paleozoic Period. Important Facts About the Outer Planets. Jupiter's Core vs. Earth's Core. Why Is the Rock Cycle Important? How is the Sun Nuclear Energy? What Are the Elements of Uranus? For years, geologists have turned to the APS to study the composition of rocks and the oxidation state of the iron contained within them.
When the time came for the scientists to have their samples analyzed, there was an obvious place to go. The beamline he works on can focus its beams to as small as 1 micron across — about 50 times smaller than the width of a human hair — giving scientists the ability to make very precise and accurate measurements of their samples.
In the s, Stanley Miller conducted a groundbreaking experiment at the University of Chicago showing that amino acids — the building blocks of life — would form in an environment with liquid water and air rich in methane and ammonia when zapped with electricity to simulate lightning.
At the time, these were the conditions believed to exist on the early Earth. On Earth, liquid water formed out of this magma-made atmosphere, pulling carbon dioxide out of the air and into newly forming oceans.
Now that Sossi has figured out what type of atmosphere forms from a magma-Earth, he is setting his sights on the stars. Using a modification of this experimental technique, he hopes to find a way to measure atmospheric composition using infrared so that one day we can use satellites to study magma worlds that may actually exist in other solar systems today.
The U. The APS provides high-brightness X-ray beams to a diverse community of researchers in materials science, chemistry, condensed matter physics, the life and environmental sciences, and applied research.
For example, volcanoes release high quantities of carbon dioxide. Iron-based compounds are present in very old rocks that could only have formed if there was little or no oxygen at the time. So how did the proportion of carbon dioxide in the atmosphere go down, and the proportion of oxygen go up? The proportion of oxygen went up because of photosynthesis by plants. The proportion of carbon dioxide went down because:.
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