NASA plans to return samples from Mars by 2031. They believe that there is no surface life in Jezero crater but astrobiologists can’t yet rule out surface microhabitats, where life might survive from a more habitable early Mars. NASA agrees it needs to protect Earth from the possibility of native Martian life in the samples.Most of our laws to protect Earth’s biosphere didn’t exist in 1969. The Apollo sample returns had no legal review. With many lapses of containment, they are now seen as an example of how not to protect Earth.NASA's proposal will get careful scrutiny. We find that this may change build requirements. The sample return study by the European Space Foundation from 2012 requires 100% containment of starvation stressed nanobacteria. These pass through 0.1 micron nanopores, far beyond the limits of testing for HEPA or ULPA filters. If this becomes a legal requirement, the technology doesn't yet exist, even as experimental filters in laboratories.NASA is not permitted to risk such a high level of public funds (~$500 million), until they know if their proposed design will be accepted or modified. The requirements could change through to the end of the legal process of 8+ years. Adding 11+ years for the build, we find that NASA won't be ready for unsterilized samples from Mars before 2039 with delays likely.It's possible to sterilize samples at a level sufficient for planetary protection while preserving astrobiological and geological interest. This becomes an unrestricted sample return; a relatively simple process under the Outer Space Treaty.However, there may be interest in the possibility of viable present day life in the samples. If so, we propose NASA return them to a holding satellite in a stable inclined orbit above GEO in Earth's Laplace plane or "ring plane". This particular orbit has many advantages for protection of Earth, the Moon, and other satellites. Sterilized subsamples can be returned to Earth immediately, so there's no delay for geological studies. If the unsterilized samples are of astrobiological interest, scientists can study them from Earth, teleoperating instruments already designed to search for life in situ on Mars, but with almost no latency. We can decide what to do next based on what they discover.This article examines specific worst case scenarios, such as a blue-green algae with everything flipped as in a mirror: DNA spirals the other way; amino acids, carbohydrates, sugars, all are in their mirror forms. A mirror cell should function identically to a normal cell but most ordinary terrestrial life can't make any use of its mirror organics.Synthetic biologists have started a step by step process to flip a terrestrial cell of normal life to mirror life. They warn that such life, if released from the lab, could gradually transform organics in terrestrial ecosystems to indigestible mirror organics giving it a competitive advantage over terrestrial life.To keep Earth safe, synthetic mirror cells will depend on chemicals only available in the laboratory. We might have to leave any Martian mirror life in orbit to achieve a similar level of safety.In the worst case scenarios Mars's biosphere can never mix safely with Earth's. Sometimes quarantine of returning astronauts is also insufficient to protect our biosphere. In other scenarios Martian life is harmless.Future possibilities, and opportunities, open to us depend on whether there is life on Mars and what it's like. Answering this seems a top priority for space colonization enthusiasts and astrobiologists alike.With a combined effort, astronauts could conduct rapid surveys of the most important potential habitats from orbit around Mars, via telepresence. Humans in orbit could control surface robots with minimal latency. This would help resolve these questions as fast as possible.We also suggest that the ESA fetch rover is modified to return a sample of dirt, including the brine layers discovered by Curiosity, to resolve the puzzling Viking lander results. Are these the result of complex chemistry or native life? We also suggest collecting some of the dust to study whether terrestrial microbes could propagate in dust storms and to start a search for dust storm resistant Martian propagules.There is no other terrestrial planet within reach, to study chemical processes on a planet left for billions of years without life. If the apparent circadian rhythms in the Viking experiment are due to complex chemistry, could this be relevant to understanding the chemistry of planets before the first living cells?This mission can easily miss present day life even if it exists in the region explored by Perseverance. However, we can maximize chances of success. Whatever we detect is a useful first step to inform future searches.This article concludes that the complex laws already in place to protect Earth’s biosphere are both understandable and necessary.

In the late 2020s to 2030s, China, and NASA / ESA and Japan plan to return samples from Mars. We need to keep Earth’s biosphere safe from any Martian microbes. Japan’s agency JAXA has the simplest mission, to return samples from the top few centimeters of Mars’s innermost moon Phobos. JAXA can safely return unsterilized samples without any precautions, because any microbes already withstood ejection from Mars, most recently, 700,000 years ago. Then on Phobos they were sterilized similarly to martian meteorites arriving at Earth today from that ancient impact.JAXA warned this meteorite argument is not valid for samples from the Martian surface. NASA’s draft EIS incorrectly says any life from Jezero crater can get here faster and better protected in a meteorite than in a sample tube. Surface dirt and dust can’t get here at all.NASA’s EIS also proposes to return its samples to a Biosafety Level 4 facility. However, the European Space Foundation study in 2012 set size limits well beyond capabilities of a BSL-4 and indeed beyond any current air filter capabilities.We can avoid all these issues and keep Earth 100% safe by sterilizing samples before they get here, with the equivalent of a few hundred million years of Mars surface ionizing radiation. This has virtually no effect on geology, while terrestrial contamination in Perseverance’s samples makes most astrobiology impossible.We can greatly increase science value with contamination free samples in a sterile container returned to a martian gravity centrifuge in an unmanned satellite above GEO, to start Sagan’s “vigorous program of unmanned exobiology”. This is a review of central results in planetary protection literature, with new worst case scenarios such as mirror life, to encourage space agencies to ensure Earth’s biosphere is adequately protected when they return samples from Mars.

The cites for this draft NASA EIS are so flawed that it’s unsalvageable. The statements they make contradict the findings of numerous panels of experts in the Mars sample return studies including the ones they themselves cite.If NASA uses this as their final EIS, and it gets taken to the courts, NASA won’t have a case, It will fail basic review, just checking the EIS’s own cites.However, I suggest with some changes the proposed action can go ahead in a way that is safe for the environment and maximizes return for astrobiology and geology.What this EIS proposes is similar to building a house without smoke detectors. But a house for nearly 8 billion people, most of whom are not aware that this decision is being made for them by NASA. This smoke detector analogy is from Margaret Race from her contribution "No Threat? No Way" (Rummel et al., 2000) We need to examine this properly and if it is needed we need to install those smoke detectors. To do this requires an adequate EIS that uses the sources correctly and it needs to consider alternatives designed to protect Earth with 100% safety, and not just “no action”In this proposal NASA plan to return unsterilized Mars samples to a biosafety level 4 facility on Earth – and to examine them for life sciences using BSL-4 precautions and then sterilize samples that are taken out of the BSL-4 facility.The European Space Foundation determined in 2012 that Mars samples should be contained to far higher standards than BSL-4 to protect Earth. This draft EIS doesn’t cite the ESF report which reduced the size limit from 0.25 to 0.05 microns. Even a decade later the technology the ESF require doesn’t yet exist even for experimental filters in laboratories, today. For details see this section and the following sections (below):We do know how to contain known hazards such as anthrax safely. However until we know what’s in the sample we can’t discount the possibility of something far harder to contain than anthrax.The worst case would be starvation limited ultramicrobacteria which have been observed to pass through 0.1 micron nanopores, or perhaps even a hypothetical ribocell which may be able to pass through a 0.02 micron nanopore. Research since 2012 makes ribocells more plausible than it was then and the ESF study in 2012 said it needs regular review. It is not at all clear that a new review would decide that a 0.05 micron standard is sufficient.NASA haven’t commissioned any new review and they haven’t even consulted the 2012 review. In this EIS they are relying on a review conducted in 2009 which is 13 years ago. A lot has changed in scientific understanding of microbes, extremophiles and the possibilities for extraterrestrial life in those 13 years.This proposal surely shouldn’t go ahead until we have had an updated review of what is needed. It is impossible to evaluate the technology requirements until we know the size limit that needs to be targeted.A simple way to install those “smoke detectors” is to require the lab for UNSTERILIZED materials and potentially viable martian microbes to be in orbit or somewhere unconnected with Earth's biosphere - unless we can prove that -there is no life in the sample OR -the life can’t harm Earth in any way OR-we know how to contain the life after return to Earth with truly zero risk.The lab also has to have no connection with Earth’s biosphere so all sample handling has to be done remotely from Earth using telerobotics. Quarantine won’t work to protect Earth from, say, a mold that is harmless to humans but attacks crops, or mirror ultramicrobacteria.Sterilized samples can return to Earth and be studied in normal labsThis leads to 100% safe sample return. Why have less than 100% safety when there is even a tiny chance of large scale effects for the whole Earth in an ultra low probability worst case?As Carl Sagan once put itThe likelihood that such pathogens exist is probably small, but we cannot take even a small risk with a billion lives.

This paper focuses on the arguments in NASA’s draft EIS which claims that life can be transferred more easily from Mars to Earth in meteorites than in the sample tubes. It also claims that there is no significant risk of effects on the environment These statements are at odds with the cites they themselves cite on these topics. This paper shows that the literature doesn’t support their conclusions and that there are many papers that raise significant concerns for the potential for large scale effects on the environment which they don’t refer to.This paper focuses on the literature on whether life can be transferred from Mars to Earth on meteorites, the literature on the potential for large scale effects, on public involvement and on the legal process.This paper also includes for motivation a brief summary of why the published literature says that there is potential for extant life in Jezero crater either in microhabitats in a seemingly uninhabitable desert in biofilms similarly to the seemingly uninhabitable Mars analogues of the McMurdo dry valleys and the hyperarid core of the Atacama desert. This will be expanded on in a follow up paper.As Rummel at al wrote (Rummel et al, 2002:96)., “Broad acceptance at both lay public and scientific levels is essential to the overall success of this research effort.”This is part of a series of papers in which we find that the cites for NASA’s draft EIS are so flawed that a clean restart is needed with a properly peer reviewed study to assess the environmental impact correctly. If NASA uses this as their final EIS, and it gets taken to the courts, NASA won’t have a case, It will fail basic review, just through checking the EIS’s own cites. However, I suggest with some changes the proposed action can go ahead in a way that is safe for the environment and maximizes return for astrobiology and geology.What this EIS proposes is similar to building a house without smoke detectors. But a house for nearly 8 billion people, most of whom are not aware that this decision is being made for them by NASA. This smoke detector analogy is from Margaret Race from her contribution "No Threat? No Way" (Rummel et al., 2000) We need to examine this properly and if it is needed we need to install those smoke detectors. To do this requires an adequate EIS that uses the sources correctly and it needs to consider alternatives designed to protect Earth with 100% safety, and not just “no action”The issues that need to be addressed in this draft EIS are so many and so serious that they can’t be covered adequately in a single paper. The reason for writing these papers is to have credibility during the NEPA review process, for any potential legal appeals, and if necessary, for the presidential review for large scale effects. Other issues will be covered in subsequent papers.

We assume that NASA and ESA wait until the legal requirements are clear before they start work on the Mars sample receiving facility. In that case, it is a minimum of 19 years to complete the process of legal approval for a martian sample return, construct the facility and be ready to receive samples. Ideally we should have started the legal process well before 2010 for ESA’s 2026 sample retrieval mission. However NASA’s Perseverance rover has not been equipped with the astrobiological instruments designed to detect present day life in situ. It also can’t drill deep enough for a proper search for past life. Any organics in its samples are more likely to come from meteoritic and comet infall, and to be as ambiguous for central questions in astrobiology as the organics in ALH84001. It is important not to raise public expectations. By its design, Perseverance is primarily a geological mission, and only a technological demonstration for astrobiology. With that background, the simplest way to protect Earth’s biosphere is to sterilize the sample, which would then not need any special precautions to protect Earth’s biosphere. Geologists could account for the sterilizing radiation for radiometric dating, just as they do for martian meteorites. Meanwhile if there is life in the sample it can still be recognized as such. However, it would be of astrobiological interest to “grab some dirt” as Chris McKay once suggested. The dust might contain spores of wind dispersed martian life, and could answer many questions about survivability of spores in the dust. Another interesting sample would be a scoop of material from a depth of a few centimeters, to sample the brine layer found by Curiosity. This would help us understand the Viking labeled release experimental data from the 1970s. This layer is of astrobiological interest whether or not it returns life. If observations suggest the samples have a significant chance of containing life, we propose returning them unsterilized, initially to a high orbit above GEO, as part of a measured step by step process that keeps Earth protected at all stages in an evidence based approach. At each stage we only build what is needed, minimizing legal complexities and cost, and maximizing science return. We look briefly at worst case scenarios such as sample return of a mirror biology cyanobacteria. We suggest that extreme caution is needed until the samples are well characterized. We conclude that the complex legal process is both understandable and necessary.