Biosignatures & Paleobiology: September 2015

By analyzing iron isotopes against the uranium content in the jasper rock from the ancient ocean of the Barberton Greenstone Belt in South Africa, scientists have found a defined vertical redox gradient, called a redoxcline, showing a change in the level of oxygenation from the deeper part of the ocean leading to the shallower portion.

The Earth's atmosphere contains oxygen because plants continuously produce it through photosynthesis. This abundant supply of oxygen allows life forms like animals to flourish.

We report a detection of water vapor in the protoplanetary disk around DoAr 44 with the Texas Echelon Cross Echelle Spectrograph - a visitor instrument on the Gemini north telescope.