and shall be the province of all mankind” [2.85]. This has come to be known as the Common Heritage of Mankind Principle or CHP. The principle “confers on a region the designation of domino util or beneficial domain that should be legally defined as a res communis humanitatis, a common heritage that is not owned by any nation, but from which all nations may garner profits and benefits” [2.71]. Rather than national interests, the UN works with planetary interests. What about the interests of extraterrestrials?
Hart lifts up for us the ethical norm of a cosmic commons which takes into account the interest of the extraterrestrials.
“The cosmic commons is the spatial and local context of interactions among corporeal members of integral being who are striving to meet their material, spiritual, social, and aesthetic needs, and to satisfy their wants….The cosmic commons includes the aggregate of goods which, beyond their intrinsic value, have instrumental value in universe dynamics or as providers for the well-being of biotic existence. In the cosmic commons, goods that will eventually be accessible on the moon, asteroids, meteors, or other planets should prove useful to humankind, to other intelligent life, and to biokind collectively” [2.32].
Might Hart’s notion of a cosmic commons help us move forward from quandary to responsibility? Yes.
Perhaps some elements of the Roman Catholic concept of the “common good” could bleed over into our concept of the cosmic commons. “The common good as sum of the goods possessed by many and directed toward the utility of individuals,” writes Sergio Bastianel, “will be the common reaching out to realize a way of living together that can be accurately called communion” [2.6]. Or, the common good “indicates an ultimate goal of society, its utopia, in such a way that the intermediate aims will be critically evaluated in their being conformed toward such an aim of communion” [2.6]. For the near future, the commons will be shared by all of us who live on planet Earth. Perhaps in the more distant future, after we will have encountered extraterrestrial life and incorporated that life into our commons, the community of moral discernment will broaden. In short, our ethical vision directs our gaze toward a future communion shared by earthlings and spacelings.
Hart is not alone in proffering the idea of a cosmic commons as an ethical category. Like Hart and Dick, Mark Lupisella at NASA’s Goddard Space Flight Center proposes a “cosmocentric ethic,” which he contends “may be helpful in sorting through issues regarding the moral considerability of primitive extraterrestrial life as well as other ethical issues that will confront humanity as we move into the solar system and beyond” [2.42].
Arnould uses the term “Greater Earth” to communicate the same basic notion, although perhaps more limited in space. “Greater Earth defines the area, the space territory that surrounds the Earth and where most future space activities could take place” [2.3]. The Greater Earth within our solar system would host economic activities and provide the sphere of terrestrial moral responsibility. What we see here is a growing convergence toward the vision of a cosmic commons—whether called “Greater Earth” or a “cosmocentric ethic”—that makes the entire human community on Earth responsible for ethical deliberation and includes in our sphere of moral responsibility everything in space we can influence.
My preferred term, as I’ve already indicated, is “galactic commons” or “galactic common good.”
2.3 Astroethical Quandaries Arising Within the Solar Neighborhood
The discipline of astroethics responds to earthlings going to space whether or not we meet new extraterrestrial neighbors. “Clearly, the ‘holy grail’ of astrobiology would be the actual discovery of life elsewhere in the Universe, and such a discovery would have profound scientific and very likely also philosophical and societal implications,” exclaims Ian Crawford; “Needless-to-say, there will also be significant scientific and philosophical implications if extraterrestrial life is not discovered, despite ever more sophisticated searches for it” [2.20]. If “astrobioethics” within “astroethics” would focus directly on quandaries arising from engaging off-Earth life, then the more encompassing category of “astroethics” would include matters that may or may not involve off-Earth life forms.
We turn now to ten astroethical quandaries arising within our solar neighborhood, quandaries already familiar to astrobiologists: (1) planetary protection; (2) intrinsic value of off-Earth biospheres; (3) application of the Precautionary Principle; (4) space debris; (5) satellite surveillance; (6) weaponization of space; (7) scientific versus commercial space exploration; (8) terraforming Mars; (9) colonizing Mars; and (10) anticipating natural space threats [2.65].
2.3.1 Does Planetary Protection Apply Equally to Both Earth and Off-Earth Locations?
Our mandate for Planetary Protection (PP) is made clear in Article IX of the 1967 UN Outer Space Treaty. “Parties to the Treaty shall pursue studies of outer space including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of the Earth resulting from the introduction of extraterrestrial matter and, where necessary, shall adopt appropriate measures for this purpose…” [2.85]. This version of the PP principle seems to make it clear: we are morally obligated to protect both Earth and other celestial bodies.
The risk of contamination goes in two directions, forward and backward. The possibility of “forward contamination” alerts us to the risk of disturbing an already existing ecosphere; the introduction of Earth’s microbes carried by our spacecraft or equipment could be deleterious to an existing habitable environment. During the SARS-CoV-2 pandemic, NASA issued two interim directives (NIDs) to protect both the Moon and Mars from forward contamination brought by earthlings [2.53]. “Back contamination” would occur if a returning spacecraft brings rocks or soil samples that contain life forms not easily integrated into our terrestrial habitat. When Apollo 11 returned to Earth in 1969 from its Moon landing, it brought Moon Rocks which President Richard Nixon divided into rice grain sized pieces and distributed to each of the 50 states and 135 nations as souvenirs. To this date, no earthling has suffered from back contamination.
Are we earthlings equally concerned about both our own planet and each off-Earth site? Not in practice. In practice, prevention of backward contamination trumps protection against forward contamination. Although forward contamination is a matter of concern, some forward contamination is permissible, opine NASA scientists Catharine Conley and John Rummel. What is not at all permissible is backward contamination. Preventing harmful contamination of the Earth must be of the “highest priority” for all missions [2.73].
Even so, PP in principle includes moral concern for protecting off-Earth bodies from Earth’s contamination. “Planetary protection covers explicitly the search for extraterrestrial life and also the potential for Earth life to interfere with future human objectives” [2.17] [2.18]. As we proceed to refine astroethics, we should ask: Might one or another off-Earth biosphere hold intrinsic value? And, if so, might this heighten our responsibility for protecting it from contaminants from our home planet?
2.3.2 Does Off-Earth Life Have Intrinsic Value?
In 2020 a possible biosignature was spotted on Venus. It is not life itself, to be sure. Rather, it is a spectral fingerprint, a light-based signature of phosphine in Venus’ harsh sulfuric atmosphere. Even if there is no life on the 900-degree surface, perhaps microbes make their home in the Venusian clouds.
NASA scientists have long given credence to the panspermia hypothesis, namely, that a wandering asteroid entered our solar system during planet formation and seeded both Mars and Earth with life. This means life on Mars and Earth would turn out to be sisters, so to speak. But life on Venus and Earth would be strangers.
On the one hand, if the panspermia hypothesis gets confirmed, we could work with the assumption that the universe underwent a single origin of all life. This would make Martian life like Earth life. On the other hand, if the Venusian hypothesis gets confirmed, then this would mark a 2nd genesis of life. The sulfuric origin