Stardust makes up 97 per cent of our bodies
http://www.asianage.com/life/more-features/090117/stardust-makes-up-97-per-cent-of-our-bodies.html
The six most common elements of life on Earth - including more than 97 per cent of the mass of a human body - are carbon, hydrogen, nitrogen, oxygen,
sulphur and phosphorus. It is an undeniable fact that most of the essential elements of life are made in stars, researchers said. "For the first time,
we can now study the distribution of elements across our Galaxy," said Sten Hasselquist of New Mexico State University in the US.
"The elements we measure include the atoms that make up 97 per cent of the mass of the human body," Hasselquist said. The new results come from a catalogue
of more than 150,000 stars; for each star, it includes the amount of each of almost two dozen chemical elements.The new catalogue includes all of the "CHNOPS
elements" - carbon, hydrogen, nitrogen, oxygen, phosphorous, and sulphur - known to be the building blocks of all life on Earth.
This is the first time that measurements of all of the CHNOPS elements have been made for such a large number of stars. Researchers used spectroscopy to make
measurements. Astronomers in the Sloan Digital Sky Survey have made these observations using the APOGEE (Apache Point Observatory Galactic Evolution
Experiment) spectrograph on the 2.5 metre Sloan Foundation Telescope at Apache Point Observatory in New Mexico.
This instrument collects light in the near-infrared part of the electromagnetic spectrum and disperses it, like a prism, to reveal signatures of different
elements in the atmospheres of stars. A fraction of the almost 200,000 stars surveyed by APOGEE overlap with the sample of stars targeted by the NASA Kepler
mission, which was designed to find potentially Earth-like planets.