Recently in the Biosignatures & Paleobiology Category

If you were looking for the signatures of life on another world, you would want to take something small and portable with you.

An atmospheric haze around a faraway planet -- like the one which probably shrouded and cooled the young Earth -- could show that the world is potentially habitable, or even be a sign of life itself.

A new study shows that iron-bearing rocks that formed at the ocean floor 3.2 billion years ago carry unmistakable evidence of oxygen.

Oldest Known Redox Gradient Discovered

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.

We model the atmospheres and spectra of Earth-like planets orbiting the entire grid of M dwarfs for active and inactive stellar models with Teff = 2300K to Teff = 3800K and for six observed MUSCLES M dwarfs with UV radiation data.

Understanding whether M-dwarf stars may host habitable planets with Earth-like atmospheres and biospheres is a major goal in exoplanet research.

To find life in the universe, it helps to know what it might look like. If there are organisms on other planets that do not rely wholly on photosynthesis -- as some on Earth do not -- how might those worlds appear from light-years away?

Planets with volcanic activity are considered better candidates for life than worlds without such heated internal goings-on.