Scientists have discovered oxygen molecules in deep space in a region of the Orion nebula, some 1,500 light years from Earth. The findings, published in the Astrophysical Journal, are the same molecules that make up one-fifth of the air breathed on Earth.

The discovery was made with the European Space Agency's Herschel Space Observatory, which used its large telescope and infrared detectors to find the elusive molecules.

Atomic oxygen (individual oxygen atoms) is common in space, and although scientists believe oxygen molecules (two bonded oxygen atoms) also to be common, it is the first time the existence has been confirmed with certainty, ending a 230-year long search, to the relief of researchers.

"Oxygen gas was discovered in the 1770s, but it's taken us more than 230 years to finally say with certainty that this very simple molecule exists in space," said Paul Goldsmith, NASA's Herschel project researcher at the agency's Jet Propulsion Laboratory (JPL) in Pasadena, California. He is also the lead author of the report.

For decades, astronomers searched for oxygen molecules using balloons and telescopes from earth and space. The molecule was spotted in 2007 by the Swedish Odin telescope but has not been confirmed until now. With this discovery, scientists will begin exploring other star-forming regions for more oxygen molecules.

Must Read: First Oxygen Molecules Found in Orion Nebula [PHOTOS]