Rosetta Space Probe And Philae Module, 67P/Churyumov–Gerasimenko Comet, European Space Agency

Previous observations have shown that comets contain complex organic compounds. These are molecules that are rich in carbon, hydrogen, oxygen, and nitrogen. These are the elements that make up nucleic acids and amino acids, essential ingredients for life as we know it. Comets are thought to have delivered a vast quantity of water to Earth, and they may have also seeded Earth with organic molecules. Rosetta and Philae will also search for organic molecules, nucleic acids (the building blocks of DNA and RNA) and amino acids (the building blocks of proteins) by sampling and analysing the comet's nucleus and coma cloud of gas and dust, helping assess the contribution comets made to the beginnings of life on Earth.
• Amino acids
Upon landing on the comet, Philae will also test some hypotheses as to why essential amino acids are almost all "left-handed", which refers to how the atoms arrange in orientation in relation to the carbon core of the molecule. Most asymmetrical molecules are oriented in approximately equal numbers of left- and right-handed configurations (chirality), and the primarily left-handed structure of essential amino acids used by living organisms is an anomaly. One hypothesis that will be tested was proposed in 1983 by William A. Bonner and Edward Rubenstein, Stanford University professors emeritus of chemistry and medicine respectively. They conjectured that when spiralling radiation is generated from a supernova, the circular polarization of that radiation could then destroy one type of "handed" molecules. The supernova could wipe out one type of molecules while also flinging the other surviving molecules into space, where they could eventually end up on a planet.