Biosphere

The biosphere (which is technically a spherical shell) is virtually a closed system with regard to matter,[1] with minimal inputs and outputs.

[2] By the most general biophysiological definition, the biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the lithosphere, cryosphere, hydrosphere, and atmosphere.

[5] The term "biosphere" was coined in 1875 by geologist Eduard Suess, who defined it as the place on Earth's surface where life dwells.

It is an interdisciplinary concept for integrating astronomy, geophysics, meteorology, biogeography, evolution, geology, geochemistry, hydrology and, generally speaking, all life and Earth sciences.

Geochemists define the biosphere as being the total sum of living organisms (the "biomass" or "biota" as referred to by biologists and ecologists).

[22][23][24][25] According to biologist Stephen Blair Hedges, "If life arose relatively quickly on Earth ... then it could be common in the universe.

[26][27][28] Marine life under many forms has been found in the deepest reaches of the world ocean while much of the deep sea remains to be explored.

[32] Barophilic marine microbes have been found at more than a depth of 10,000 m (33,000 ft; 6.2 mi) in the Mariana Trench, the deepest spot in the Earth's oceans.

[33] In fact, single-celled life forms have been found in the deepest part of the Mariana Trench, by the Challenger Deep, at depths of 11,034 m (36,201 ft; 6.856 mi).

Experimental biospheres, also called closed ecological systems, have been created to study ecosystems and the potential for supporting life outside the Earth.

Based on observations by the Kepler Space Telescope team, it has been calculated that provided the probability of abiogenesis is higher than 1 to 1000, the closest alien biosphere should be within 100 light-years from the Earth.