what are two ways that scientists have studied space debris as a possible origin of organic compounds on Earth? What did they discover in each case? (2) What is the evidence that the first life may have evolved around geothermal vents?

1) One way is through radiographs. Scientists have studied the spectrum that distant nebulas give off and they have managed to identify molecules that can be found in there. Among them there is hydrogen and various nitrogen and carbon molecules; even alcohol has been found some of them. Another way is by sending probes to asteroids that check not only for simple organic molecules but also aminoacids and nucleotides. A third way was the Urey Miller experiment. There, some basic atoms that can be found in space (nitrogen, hydrogen and carbon) where put together with a spark in a flask. The mixture turned brown and produced complex organic molecules quite soon. This finding makes a case for complex organic molecules being produced in space and thus it is possible that they were transferred to Earth.

2) Geothermal vents are a source of hot water and raw nutrients such as sulphur. The main theory about the genesis of life around vents is that the cells started exploiting the pH or the thermal gradient near those vents and thus had a way to produce energy. The experimental set up for this is a chemical garden, an environment that simulates those alkaline and metallic conditions and yields hollow, plant-like structures. Also some metals in the vents are great catalysts for chemical reactions in organisms. Also fossilised microbes have been found beneath such vents.