Stretching Twelve AstroEthical Issues within our Solar Ghetto to Address Warfare in the Milky Way Metropolis


By Ted Peters, METI International Advisory Council

METI scientists need to defend their message-sending to possible new neighbors on planets elsewhere in the Milky Way metropolis. Fearing that hostile aliens will receive these messages and order their armies to conquer and colonize Earth, METI critics such as Stephen Hawking raise a challenging ethical question. How might we connect this question with a dozen other astroethical questions formulated to deal with space exploration within our solar ghetto? (1) does planetary protection require protection of off-Earth ecospheres? (2) do extraterrestrial microbial life and of off-Earth ecosystems have intrinsic value? (3) should space scientists invoke the Precautionary Principle? (4) should earthlings clean up space junk? (5) what should we do about satellite surveillance? (6) should we weaponize space?  (7) how should we adjudicate the competition between scientific research and economic interests, including space tourism? (8) should we terraform Mars? (9) should we colonize Mars? (10) how can we protect Earth from extraterrestrial threats such as solar flares, asteroid collisions, and gamma bursts? (11) does astroethics require a single planetary community of moral deliberation? (12) should we stretch the common good into a cosmic commons? Can we stretch these existing ethical issues drawn from within our immediate solar ghetto to include the entire Milky Way metropolis, including our first encounter with exoplanetary civilizations?

METI's objective to understand and communicate the societal implications and relevance of searching for life beyond Earth warrants ethical deliberation and even speculation. Here is a whopper of an ethical question: might METI transmissions lead earthlings into an inter-planetary war? Stephen Hawking tells us to worry about this. The crux of Hawking’s warning is that if there are malevolent aliens out there, we had best hush up, or we risk an invasion from their conquering armies (Hawking). In short, shut down METI! John Traphagan tells us not to worry. If aliens are like earthlings and even have warfare in their history, they may still have a self-understanding of being peaceful (Traphagan). In short, continue with the METI mission! So, we ask: how should earthlings prepare for first interstellar encounter? Might this question fit side-by-side with others on the astroethicist's agenda?

In what follows I would like to list twelve already existing ethical issues--smaller than whoppers yet still important--arising from space exploration. Might the METI debate regarding possible interplanetary warfare connect with the more modest astroethical agenda? If so, how?

1. Does Planetary Protection Apply to Earth Alone?

NASA already sponsors a Planetary Protection desk due to the threat of interplanetary contamination. 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. Back contamination would occur if a returning spacecraft brings home rocks or soil samples that contain life forms not easily integrated into our terrestrial habitat. A quarantine program will be required to determine the safety of newly introduced non-intelligent life.

Prevention of backward contamination has trumped protection against forward contamination in actual practice. After the first landing on Mars, subsequent Mars landers were not decontaminated before takeoff. Decontamination is expensive. What should become terrestrial policy for extraterrestrial exploration?

If the METI interstellar war question should gain moral traction, should we place it within the existing planetary protection orbit? Or, would protecting our planet from alien armies become an independent concern? On whose shoulders does the moral duty to protect Earth from interstellar invaders rest?

2. Does Extraterrestrial Life Have Intrinsic Value?

This is the dignity question. We treat terrestrial Homo sapiens with dignity--that is, it is morally right for us to treat each person as an end and not merely a means to a further end. Modern Western morality proscribes treating human beings as mere instruments for some higher goal or value.

What about non-human life? On Earth we value life just because it is life, to be sure; but we do not value life absolutely. When we wash our hands or dishes in detergent, we kill microbes by the millions. At what point is it moral to protect life and what justifies destroying life? We need to become clear on what we presuppose before we can formulate policies for treating whatever simple life forms we discover on Mars or the moons of Saturn.

Even if exoplanetary intelligent creatures might become enemies of Earth, should we earthlings confer on them intrinsic value? Will intelligent creatures in space warrant our treating them with dignity even if they become our enemy?

3. Should Space Explorers Invoke the Precautionary Principle?

Because of our present ignorance regarding off-Earth ecospheres and the risk that we might destroy an extraterrestrial habitat, should intra-solar space explorers adopt the Precautionary Principle? Formulated by United Nations' eco-ethicists in 1992, the Precautionary Principle reads like this: “When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. In this context the proponent of the process or product, rather than the public, should bear the burden of proof" (Appell, 2001, 18). Might the Precautionary Principle provide ethical guidance for at least the next decade of intra-solar space exploration?

The Precautionary Principle, despite its name, applies only to terrestrial science. It does not seem to have any application to the interstellar warfare question.

4. Should We Clean Up Our Space Junk?

Like dirty birds, we earthlings befoul our nest. Ecologists fear that we are gradually making Earth uninhabitable. Will we also contaminate space?

We already have. Jacques Arnould, astroethicist for the French Centre Nationale d'Etudes Spatiales (CNES), warns us: “there are now 22,000 human-made objects larger than 10 centimeters across in orbit and half a million larger than 1 centimetre—and all pose a grave risk to space missions....Even if space agencies never launched another rocket, the cloud of debris will continue to grow as a pieces of space junk crash into one another” (Arnould, 2011, 92). Who should pay for the clean up?

The question of space junk seems to be just a circumterrestrial one, a local concern of earthlings. Now, if we proceed to invite exoplanetary aliens to come to Earth for dinner, then we might want to clean up our space junk before they arrive. Their arriving spacecraft should not have to tip toe through our debris. After all, we'd like to leave a good impression on our visitors.

5. What Should We Do About Satellite Surveillance?

Over the last sixty years, reconnaissance satellites or spy satellites have been deployed for purposes of military and other intelligence applications. The telescopes on board are pointed toward Earth, not toward the stars. Mission tasks include high resolution photography; measurement and signature intelligence; communications eavesdropping; covert communications; monitoring of nuclear test ban compliance; and detection of missile launches. With the improvements in technology, today's spy satellites have a resolution capacity down to objects as small as twelve centimeters. Surveillance satellites also provide us with efficient communications, weather reporting, Google maps, and many more public services.

How should we go forward? Here is what I recommend: an ethic of maximal information without discrimination. Rather than attempt to police information gathered from remote sensing, it would be healthier and easier to prevent such information from deleterious usage.

Could we turn orbiting snooper satellites outward to spy on intelligent aliens? Or, is this what SETI is already doing?

6. Should Nations Weaponize  Space?

Is it the responsibility of the spacefaring nations--perhaps with the United Nations as their vehicle--to secure and protect the peaceful use of Earth's stratosphere and orbitosphere? Peace and justice in our cosmic neighborhood inheres in ethical concepts such as the common good or the galactic commons. Traditional terrestrial warfare should not be exported to extraterrestrial locations. Should "Star Wars" be limited to the movie screen?

If we earthlings would take Hawking's alert seriously, would we arm our satellites with weapons to fend off exoplanetary invaders? Would our satellites become pawns in the interstellar game of chess?

7. Who Gets Priority: Scientific Research or Making a Profit?

Up until this point we have thought of outer space as a playground for Earth's scientists alone to play in. Governments have found the money to fund modest exploratory adventures; and scientists have organized to conduct experiments which have yielded an abundant harvest of new knowledge about our cosmos. Frequently, scientific goals have been mixed with military goals, because leaders in the military have been willing to share their budgets for scientific purposes.   Scientific experiments do very little damage, if any. The impact on our solar system by scientific activity is benign.

This situation is about to change. The private sector is now ogling space for profit. What about space tourism? Simply flying a few wealthy passengers high enough to experience weightlessness is not likely to provoke anyone's moral ire. But, what about tour busses roaming the surface of the Moon? Busses will leave tire tracks. Perhaps trash. Who will decide policy and what will be the criteria by which they decide?     

The Hawking alert regarding possible interplanetary warfare adds a third question of priority: science? business? or the military? But, then, the military is a form of business, isn't it?

8. Should Earthlings Terraform Mars?

Should we earthlings terraform Mars? Or, any other planet or moon, for that matter? Should we seed off-Earth sites with simple life, evolution, and then complex life forms? Should we make other bodies in our solar system habitable for humans? Can we earthlings rest content before we see the golden arches of McDonalds on the red planet?

NASA Mars researcher Christopher McKay addresses the issue of terraforming Mars with a prime moral axiom: life is better than non-life. "I suggest that the long-term goal for astrobiology and society is to enhance the richness and diversity of life in the Universe" (McKay, 2013) 159).  Virtually no one who mulls over the question of life's intrinsic value would challenge McKay's starting point: life is better than non-life. But, we ask: what comes next? Colonization?

The terraforming of Mars might deflect aggression against us on Earth. Mars might become so attractive that exoplanetary explorers might prefer to settle on the red planet instead of Earth.

9. Should Earthlings Colonize Mars?

There are on Earth ambitious organizations, such as the Mars Society in the U.S. and Mars One in the Netherlands, who are working like busy bees to prepare for colonizing the fourth planet from the sun. According to the National Geographic Channel on television, earthlings are on the way to the red planet (National Geographic, 2016). Is this moral?

Yes, say members of the Mars Society and the Mars One project. The human race is being called by destiny to go, go, go. To spread our race throughout the solar system fulfills our inherited evolutionary mandate, to fill every niche with life. I ask: does such a moral mandate actually exist? Are terrestrial Homo sapiens actually called by evolution to a Promethean destiny of populating outer space? If the answer is affirmative, is colonization the right thing to do?

If earthlings begin to live on Mars, then this will provide Hawking's feared colonizers with the opportunity to take over two new planets rather than only one. This will mean more real estate for us to defend. But, it also will provide us with triangulation to increase the accuracy of our defense weaponry. This will require, of course, the militarization of Mars coincident with its colonization. In short, Mars will get everything we have developed in Earth's history, including weaponry.

10. How Should We Protect Earth from Natural Extraterrestrial Threats?

Regardless of whether some earthlings become Martians, Earth will continue to be a dangerous home. The heavens hold plenty of threats. The Sun occasionally launches solar flares, which fry electricity grids. In addition to solar threats, we need to anticipate the possibility of a large comet or asteroid strike. Once or twice every two million years Earth gets smacked by rocks two kilometers or more in diameter, leading to extinctions. It is widely believed among scientists that sixty-five million years ago an asteroid twelve kilometers in diameter hit Earth and triggered the mass extinction of dinosaurs. Can we protect Earth from future asteroid catastrophes? The UN's Science and Technical Subcommittee’s Near-Earth Object Working Group and its internal panel, Action Team 14, have been working on the details of an international approach since 2001 to anticipate and thwart such Near Earth Objects (NEOs) (Haubold and Nadis, 2014).

These damage scenarios prompt us to think ahead. We need to plan for our planet's future, and we need to incorporate such possibilities into our planning. With regard to solar flares, fortunately, there are ways to mitigate the damage should it occur: engineers can protect the grid with fail-safes or by turning off the power in the face of an incoming blast. With regard to a comet or asteroid strike, we will be given advanced notice. A diversion strategy could be effective, perhaps by hitting the object while it is yet far away with a nuclear bomb. We have no way to prevent gamma ray bursts from striking our Earth, but we could provide protective shields in sanctuaries for life forms we wish to restart following the event. These matters belong to our ethical quandary. Just how will we respond?

Asteroids, solar flares, and gamma bursts are unintelligent threats. Intelligent exoplanetary civilizations might constitute an intentional extraterrestrial threat. Should we extend the model of international spying to interplanetary spying in order to anticipate such threats?

11. Does AstroEthics Require a Single Planetary Community of Moral Deliberation?

Who should engage in ethical deliberation? Who should make public policy decisions? Because every moral commitment regarding space is simultaneously a commitment regarding the entire Planet Earth, it follows that the entire planetary community should become the unit for ethical deliberation (Peters, 2013). It follows further that it should be multi-generational; today's earthly community must incorporate tomorrow's into their moral deliberations (Vakoch, 2011, 483).

In my judgment, whether astroethics is pursued by intra-solar astrobiology, SETI, or METI, the matter of establishing a single planetary community of moral deliberation is urgent.  When confronting scenarios that have a planet-wide impact such as a threatening asteroid, the planet as a whole should become the community of moral deliberation and provide the network to shoulder the responsibility. Planetary plans to meet such threats should be international or supranational. The principle of distributive justice may require that each nation contribute to a coordinated effort in proportion to its capability by providing either technological expertise or funding for such expertise.

12. Should the Common Good Include the Galactic Commons?

Only the invocation of the common good can successfully trump the current competition between vested interests, cost-benefit priorities, industrial ambitions, and international conflicts. A single planetary community of moral deliberation could arise only if the common good becomes its agenda.

Further, we note that the commons we share is larger than Planet Earth alone. It is even larger than our solar system. Why? Because Earth is nested in a larger physical context, the Milky Way galaxy. Perhaps it would wisest for the time being to designate the galactic commons as the shared home for our common good. [The idea of a cosmic commons might not be viable, because the light year problem basically forbids interactive communication. A commons for our galaxy seems plausible, however.] Perhaps wishing well those new neighbors on exoplanets will become the first item METI space explorers will put on their astroethical agenda.


Astroethics is not quite an established field, but the need for the field is beginning to surface. I forecast astroethics will quickly morph into two divisions, one for astrobiologists searching for microbial life within our solar ghetto and one for SETI and METI scientists searching for intelligent life in the Milky Way metropolis. METI and SETI space ethicists will most likely be drawn toward the Milky Way metropolis.

Can the peoples of Earth think of themselves as a single planetary society shouldering responsibility for what happens at home, in our solar ghetto, and even on exoplanets?



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