Gaia spore
Gaia spore is the concept that Gaia can reproduce via space colonization. Despite the ecological damage caused by the emergence of humanity and human technology within Gaia, their emergence is an essential part of Gaia's reproduction via spreading of earth's ecosystems to other planets. The Gaia spore concept is an explanation of the purpose of human industry within the broader Gaia-ecological value perspective.  This concept is an extension of the Gaia hypothesis that proposes that living and nonliving parts of the earth are viewed as a complex interacting system that can be thought of as a single organism.

# History
The Gaia spore concept was first formulated in the year 1998 as a framework to help the moral interpretation for the inherent conflict between the emergent ecological value systems and predominant techno-economic value systems.

# Theories
The Gaia spore concept is largely a moral tool to interpret the value of human technology within a moral system which places significant value on helping to preserve and protect Earth's ecological systems. Such a Gaia-centric moral system is antagonistic of human progress because of the increased ecological footprint and strain on Earth's ecosystems with social and technological development. 
The gaia spore theory provides a context to answer the question "what is the value of human progress" from an ecological perspective.

# Interpretation
The Gaia Spore concept can be interpreted on a number of different levels. Technological, humanistic and moral.
From a technological perspective, the Gaia spore concept represents a number of engineering and scientific challenges. These challenges are largely being addressed by NASA in exploring other planets, searching for habitable planets beyond our solar system, spacecraft propulsion and human spaceflight. Specific technologies like life support systems and antimatter propulsion may be required to successfully develop the Gaia spore vessel.
From a humanistic perspective, the Gaia spore concept represents a critical insurance for humanity's survival. Well known Physicists Professor Stephen Hawking has warned that the human race must move to a planet beyond our Solar System to protect the future of the human species. 
From a moral interpretation perspective, the Gaia spore concept has value in resolving the conflict between ecological and humanistic value systems. Human activity which is necessary to sustain the economic wealth required for the development of the Gaia spore is acceptable to Gaia as would be the physical hardship incurred in the process of reproduction by other living organisms. This framework provides a guideline for economic development but also environmental stewardship.

# Technological Challenges
Because of the complexity and interdependence of Earths life forms, there are a number of challenges to space colonization.

## Gaia Reproduction
Gaia is a highly complex interaction of plant and animal biology. Developing a biosphere which is capable of sustained survival is challenging. The failure of the biosphere 2 experiments which began in 1985 and had difficulty maintaining a balanced environment.

## Potential Gaia Progeny
Gliese 581 c is a "super-earth" extrasolar planet orbiting the red dwarf star Gliese 581. It appears to be the first terrestrial extrasolar planet discovered in the hypothetical habitable zone surrounding its star, where surface temperatures might maintain liquid water and therefore be suitable for life as known on Earth. This makes it a potential habitable location to support earth's ecology. The planet is astronomically close, at 20.4 light years (193 trillion km or 119 trillion miles) from Earth in the direction of the constellation of Libra. Its star is identified as Gliese 581 by its number in the Gliese Catalogue of Nearby Stars; with respect to Earth it is the 87th closest star system. Gliese 581 c is the first extrasolar planet believed to possibly have a surface temperature similar to that of Earth. It is the smallest extrasolar planet around a main sequence star discovered to date. The planet is about 50 per cent larger and five times heavier than Earth.
Mars, the fourth planet in our solar system, is a terrestrial planet which has a thin atmosphere which could potentially  support life. Currently, however the atmospheric pressure and temperatures on mars would not be able to support earth's ecology without significant terraforming.

# Strategic Approach
There are different strategic approaches to developing the technology and wealth
required to allow space colonization. 
An example of two different strategic approaches to space colonization are "the sprint" or
"the marathon".

## The "Sprint"
Humanity's current trajectory appears to be "the sprint" trajectory which involves a quick ecologically unsustainable build-up of wealth in order to allow the development of the gaia spore but in the end will lead to an exhaustion of Earth's resources and ultimately cause severe damage to Gaia. Gaia will no doubt recover from this abuse as it has in the past from the other extinctions, but humanity may not. This strategy has the advantage of reducing the Gaia's exposure time to the risk of major non-anthropogenic extinction events but is dangerous in that it risks humanity's own life support system.

## The "Marathon"
A "Marathon" trajectory may also be possible. This strategy is a low ecological impact method of space colonization which is more ecologically sustainable and ultimately reaches a steady state which could allow multiple colonizations over time. This strategy would first involve reducing Humanity's impact on the Earth to a stable and sustainable level and then gradually developing the wealth required to build the Gaia spore. This strategy has the advantage of protecting Gaia's life support system but could put Gaia at a higher risk of non-anthropogenic extinction events
before reproduction.