Churyumov-Gerasimenko

"Comet emits ancient molecular oxygen from its nucleus"
The origin of life on Earth has been one of the most mysterious questions scientists have investigated. One theory called the 'impact-origin hypothesis' says that life's evolution could originate in a cataclysmic collision.
In its early days, our planet saw numerous impacts from asteroids. Thousands of these space rocks crashed into the young Earth, and they came primarily from the asteroid belt, which was perturbed by the evolving orbits of the Solar System's more giant planets.
European Space Agency started a research program to learn more about asteroids and their role in discussing the origin of life. The agency launched the Rosetta mission, and the ESA probe Rosetta was sent to enter an orbit around a comet's nucleus and release a lander onto its surface. In 2014, after a 10-year journey, comet 67P/Churyumov-Gerasimenko became the first comet to be accompanied by a spacecraft for two years (2014–2016) and the first to have a lander land on it. The Rosetta mission provided a resource of minimally altered material with known origin whose structural properties can be used to further the investigation of our early Solar System. The properties of the cometary dust contain information on their basis and clues to the formation of planets. The comet emits ancient molecular oxygen from its nucleus, and the European's Rosetta probe sensor found abundant molecular oxygen. This discovery could also shed light on how early organic matter and molecules found their way to solid bodies in the solar system.