article_snippet: Scientists found traces of nitrogen compounds known as nitrates, a vital source of nutrients for living things on Earth.
article_snippet: Nasa scientists in California found nitrates - a source of nitrogen for life on Earth.
article_snippet: nitrates - a source of nitrogen for life on Earth was likely created by asteroid impacts or lightning in volcanic plumes .
article_snippet: The Earth’s nitrogen-rich atmosphere made life possible, but the origins of the air we breathe have long been a mystery.
article_snippet: Now, scientists believe scientists have found the answer: that tectonic forces responsible for creating mountains and volcanoes, also made the atmosphere habitable.
article_snippet: Geoscientists studied tectonic chemistry and found that nitrogen started building up in Earth’s atmosphere three billion years ago.
article_snippet: researchers explained in October 2014 that the chemistry of the air we breathe is the result of billions of years of photosynthesis, as well as tectonic activity.
article_snippet: While scientists knew that plant life was responsible for the build up of oxygen, which makes up one fifth of the Earth’s atmosphere, the nitrogen content - which accounts for 80 per cent of air - had remained a mystery.
article_snippet: The discoveries note that this particular nitrate likely resulted from an asteroid impact, or lightning in a volcanic plume.
highlights_snippet: Nasa scientists in California found nitrates - a source of nitrogen for life on Earth .
  
highlights_snippet: nitrates - a source of nitrogen for life on Earth was likely created by asteroid impacts or lightning in volcanic plumes .
  