Oxygen in Planetary Biospheres Workshop

Earth, the only planet we know of with life (and with scientists who hold workshops to discuss planets and life) is thoroughly and anomalously oxidized – in its atmosphere, mineralogy and biosphere. Clearly, photosynthetically-released oxygen, fueled by a nearby star, is sufficient to support a robust and diverse biosphere. But is it necessary? If so, is it a “hard step” towards single-and multi-celled eukaryotes (animals and plants), or their extraterrestrial analogs (“complex life”), including cognitive and technological life? Oxygen is commonly discussed as a biosignature. The rise of oxygen, as both an energetic “fuel” and the source of an ozone UV screen, is seen as key to Earth’s development of complex life. Yet Earth’s biosphere predates its contemporary atmospheric composition, and given astrobiology’s “N=1” problem, do we know enough to generalize this requirement? Should Earth’s history, which is marked by a geologically sudden rise of metabolically important atmospheric oxygen, be mirrored elsewhere? Are there astrophysical contexts and locations which favor the development of oxygenated planetary biospheres?

This 3-day workshop at the Green Bank Observatory will focus on topics related to the role of oxygen in the universe, planets and life, and how the rise of oxygen on Earth may (or may not) likely have analogs on other planets. Attendance is limited to 50 participants, by application only, and all registration and travel expenses will be covered.

Recognizing the challenges the pandemic has presented for networking over the past several years, this workshop will have a strong focus on early career researchers, and will have broad international participation. Presenters are encouraged to gear their talks to an interdisciplinary audience, eschewing the trees of internecine disciplinary debates for the forest of broader understanding.

Topics covered may include:

– Oxygenation events in planetary histories.
– The origin of oxygenic photosynthesis.
– Planetary oxygenation and the development of biological complexity.
– Alternatives to oxygen: complex life and atmospheric radiation screens on abiotic planets?
– Oxygen as a biosignature.
– False positives.
– How do biosignatures change with atmospheric redox state?.
– Exoplanet modeling and observations.
– Atmospheric evolution.
– The astrophysical and astrochemical context for biological origin and evolution.

This list is not intended to be comprehensive or definitive; we encourage those working on any related problems not listed here to apply.