he excitement of new horizons in Space beckons, driven by both an escape from earthly apocalypses and by the potential of new resource frontiers. As the articulations of the off-planetary military-industrial complex of so-called New Space and national interests gather pace, we should guard against hubris shaping our off-planetary practices. Those eagerly hailing Space as a solution to a ‘post-scarcity’ world, might do well to reflect on the current state of Earth; any solution to planetary dilemmas that continues the export of capitalism and its environmental imprint off-Earth should proceed with caution. We only need reflect on the damage extraction has wrought on various Earthly frontiers- now including the deep ocean, a space about which we know so very little, to appreciate the need for care and humility. In what follows, we want to offer two examples of how a twinned geographical manoeuvre of thinking upwards- but also downwards might contribute to our thinking about the politics of Space and off-planet capitalism and colonialism. We argue that, just as we turn eagerly upward and outward from Earth’s surfaces towards new horizons, we might benefit from simultaneously turning our eyes and minds inward and downward. There is, we propose, much to be learnt from entangling our looking up and out, with looking down and within, whether on or ‘off’ planet.  

Whilst our imaginaries of Space tend to privilege horizon scanning –  the extent of the farthest star, the outermost planet – these horizons are increasingly twinned with those below the surfaces of planets, moons and asteroids. Indeed, the current portfolio of NASA missions seems orientated downward. This includes Viper’s robotic lunar drilling project TRIDENT (The Regolith and Ice Drill for Exploring New Terrains); the PSYCHE mission to explore if the nickel-iron rich asteroid Psyche is the exposed core of a planet; and, the exploration of the ‘inner space’ of Mars that drives the Mars InSight Mission, including sensing marsquakes. For others, it is beneath the surface, protected within caves or locked within the composition of rocks, that the best chances of finding life off-planet exist (Boston, 2010; Perkins, 2020). Alongside such scientific missions, the capitalist potential of the subterranean frontier often tends the Earthly minds of New Space downward. Whilst early asteroid mining proposals were framed by the dream of returning rare materials to Earth, more recently extraction has been understood as primarily for in-situ use; enabling off-planet habitation and further exploration. In what follows we use two images to anchor some thoughts about the politics of thinking down and within whilst thinking up and out, entangling off-on planet undergrounds. In the first instance, we explore space dirt, building on Arboleda’s (2020) ideas to consider the lunar subsurface as part of the evolving interplanetary mine. In the second instance, we turn to lunar sky-lights and their associated caves, so-called safe havens for non-human and potentially human life off-planet. In doing so query what it might mean to re-situate terrestrial associations of caves with the origins and politics of life to lunar and even Martian subsurface spaces. 

Space Dirt : Cuius Est Solum 

Still from a NASA promotional video for the Artemis Mission, tweeted by Jim Bridenstine

At 2.31 pm on 10th September 2020, Jim Bridenstine of NASA tweeted a promotional video from the agency’s Artemis mission. The 1min 8 seconds of video began benignly enough, affirming the mission’s goals, to land the first woman and next man on the Moon by 2024, and to build a sustainable human presence on the Moon in the next decade. But then, 18 seconds in came the tweet’s point, to announce: ‘NASA is looking for companies to collect lunar samples.’ On screen, a mocked-up rover landed, and its extendable arm scooped up some soil, we were told,

to meet NASA’s requirements, a company would need to collect a small amount of lunar soil or rocks from any location on the lunar surface, provide imagery to NASA of the collection with location data, and, transfer ownership to NASA. 

Cuius est solum, eius est usque ad coelum et ad inferos, or ‘whoever’s is the soil, it is theirs all the way to Heaven and all the way to Hell,’ is an oft-quoted start point for discussions of Earthly underground ownership. Yet, developed in 18th century English law (as the translation betrays), numerous recent accounts have demonstrated this maxim’s ineffectual application to the earthly subsurface. This is due, in part to what Gavin Bridge (2013, 56) has described as the ‘split estate’, a condition of surface-sub-surface alienation, ‘so that each may be held separately.’ But also, due to the geographical variegation and general uncertainty in contemporary sub-surface regulation which challenges both utilisation and conservation (Bricker, 2017; Garrett et al. 2020; Melo Zurita, 2020; Yuan et al. 2019). In the midst of these complexities and the ongoing underground dispossessions of the colonial present on Earth, what hope for off-planet undergrounds? 

NASA followed up their promotional video detailing payments of between $15,000 and $25,000 for ‘dirt’ samples of between 50 to 500 grams (roughly five times the November 2020 price of gold on Earth). The value of these samples lies not however in their interest for scientific testing, but for their status as a legal test case. As Bridenstine explains, for the private companies (US based or otherwise) the final 80% of payment is made on the transfer of ownership of the material on the lunar surface, not on return of the samples to Earth, indeed, many samples may never reach Earth. As Bridenstine argued, ‘we’re trying to prove the concept that resources can be extracted and they can be traded, and not just traded among companies or private individuals, but also among countries and across borders-private individuals in other countries.’ With the extension of the rover’s arm, its scooping of the lunar soil and that legal transfer, NASA seems to gesture towards an off-planetary ‘cuius est solum,’ where ‘whoever’s the soil’ is less a question of the surface coming to stand (or not) for what lies above and beneath, but instead this immediate lunar underground comes to stand for all resources, if you can transfer the soil, then you can transfer water, ice, minerals and more? 

In his interrogation of the political life of extraction infrastructures Martin Arboleda (2020) explores how the increasingly ‘smart’, ‘flexible’ and ‘autonomous’ extraction industry has created a geography of extraction he terms the ‘planetary mine’ (p.6). In his book-length study he directs us toward a re-imagination of the mine as a ‘dense network of territorial infrastructures and spatial technologies vastly dispersed across space’ (Arboleda, 2020, 7). Replacing the mine as a singular site, a ‘discrete sociotechnical object’ often framed through state-based stories, this is an imagination of extraction, and so of human and non-human violences, that ‘traverses the entire geography of the earth’ (ibid). Yet, NASA’s experiments with the ownership of lunar dirt intimates that even such planetary-wide imaginations of extraction are not expansive enough. Indeed, so advanced are autonomous mining practices, and so interwoven are mining and space technologies (with some companies even being off-shoots of one-another) that we might think of our infrastructures of extraction as already becoming interplanetary. For Arboleda, the planetary mine requires ‘new territorialities of extraction’ that move beyond the state-centric frames of political economy, including ‘resource curse, dependency, imperialism’ (2020, 5). As such, the interplanetary mine demands we consider urgently the novel modalities of territorial form needed to understand and manage the environmental, social and cultural implications of extraction off-planet. 

Lunar SkyLights: Safe Havens- A Politics of Life?

Still: 2.23 into Dr Laura Kerber’s introduction to the ‘Moon Diver’

Dr Laura Kerber of NASA’s JPL, opens her 2018 lecture at the KECK institute of Space Science by gesturing towards four images of a ‘hole’ in the Moon.  The lunar skylight, some 100 metres in diameter cuts a gaping hole, one of the three largest detected on the Moon, in the Mare Tranquillitas. The hole, like the Roman goddess the lunar sea is named after, appears in its textured grey-scale, tranquil and serene. The seemingly calmly empty grainy images allow approximations of depth through calculation of shadows (about twenty giraffes Kerber tells us). Yet, we should be careful not to reproduce in the apparent emptiness of these lunar pits the same sub terra nullius that Melo Zurita (2020, 269) warns us of with respect to Earthly urban undergrounds; an ‘epistemologically blank slate waiting to be exploited with necessary technology and funding’. For, just as the imagination of terra nullius has long enabled the displacements and violences enacted by colonial pasts and presents, we should not let it determine colonial space futures. 

Well before the Japanese SELENE orbiter confirmed skylights on the Moon’s surface in 2009, there were theories and discussions about how lunar lava tubes could offer locations for (hu)manned lunar bases. Providing shelter from cosmic radiation, micrometeorites and temperature fluctuations, these lava tubes are seen as a potential site for bases on the Moon and on Mars, and have even been discussed as speculative sites for lunar cities (Perkins, 2020). It is not just human life for whom interplanetary caves might offer safe havens. Astrobiologists have long thought that so-called ‘cave candidate’  on Mars are the most likely site for finding life on the Red Planet (Boston, 2010). Rather than human-scale aliens, this is life of a microbial scale (Perkins, 2020). As with terrestrial caves, mineral precipitation and microbial growth is both supported and preserved by the often relatively stable physical and chemical conditions within a cave (Popa et al. 2012). Yet, as cave explorers on Earth have made clear, to enter these often little known ecosystems, is to disrupt and destroy the balance that is there. Should such sites become safe-havens for humans off-planet, this could mean the destruction of these other forms of life. 

Evocations of the underground as interplanetary safe haven, whether for humans or non-humans, speaks to the tension of human relations with Earthly undergrounds. On the one hand caves have long been sites of inhabitation, of safety and protection, a key to human origins, but on they are sites of unease and reluctance, dwelling challenged by darkness and inhospitable environments (McFarlane, 2019; Williams, 2008). It is difficult to imagine how humans might, as a species, settle into a lightless subterranean of outer space. Indeed, it is perhaps telling that one of the most successful space analogues the European Space Agency runs for training international astronauts is their CAVES programme. Since 2011 CAVES has sent small groups of ‘cavenauts’ on two-week missions into caves on the Italian Island of Sardinia. In vlogs, sometimes framed as ‘field reports,’ Loredana Bessone (course director) and a series of cavenauts observe that these caves offer one of the best on-Earth analogues for their off-planet experiences. Against pictures of cave exploration, scientific work, and camping in inky blackness, they detail the value of the Earthly underground’s hostility. They highlight extreme sensory deprivation and a lack of normative time parameters. In these exercises terrestrial caves, far from safe havens, come to stand for the whole of a hostile off-planet world. 

The figure of the interplanetary caves as a site for the entanglement of human and non-human life offers a twist in the long histories of the Earthly subsurface as a site for pondering human origins. As cave art expert David Lewis-Williams (2002) observes, to journey into caves is to ‘take us to the heart of what it means to be human’ (18). Recently, though, the cave has become an important topi in exploring a more expansive Anthropocene politics of life. Kathryn Yusoff  (2014), for example, summons the cave as a political site by way of the painted figures of the ‘Birdman’ of Lascaux, (Southern France, 17-22,000 ya.) and the Gwion Gwion ‘living pigment’ paintings of Kimberly (Western Australia, 17-70,000 ya.). Yusoff’s geological aesthetics evolves spelunkuler genealogies of human life into an accounting of life that forces ‘speculative questions towards novel conceptualizations of ecological arrangements; and in doing so question the boundary work that frames nature/culture, human/nonhuman, subject/ object, life/nonlife (389). In this context, to ponder lava tubes and cave candidates as safe havens for already existing non-human life and for future human habitation, is not only to query which life matters in these potentially fragile underground ecosystems, but also to address the politics of life itself. In short, if accounting for earthly geologies have reshaped the politics of life on-plant, what might happen to these politics when we consider interplanetary geologies and the scope of the off-planet inhuman? 

Writing in the 16th Century, Leonardo da Vinci observed ‘we know more about the movement of celestial bodies than about the soil underfoot’ (cited in Wolfe, 2002). Beginning from two images – of space dirt and a lunar sky light -- we have offered some observations about the value of thinking celestial bodies and their underground- the soil and below, together. Entwining undergrounds on and off-planet, draws into view the importance and potential of exploring subterranean frontiers off-Earth, but also of how thinking about the Earthly Subterranean might inform engagements with off-planet undergrounds. Entangling undergrounds helps us grapple with extreme environments, whether they be sites for human training or potential inhabitation, locations that demand new thinking about legal and regulatory frameworks, as well as the politics and ethics of extraction and of life itself. The underground has long been a crucial site for thinking about the interface of humans, technology and the environment; from Lewis Mumford’s early 20th century treatise Technics and Civilisation, which situates mining as integral to modern capitalism, to contemporary debates about the geological epoch of the Anthropocene. As such, it should perhaps be of no surprise that in thinking about the politics, ethics and potential of entangling humans, technology and off-planet environments, we might also do well to direct attention downwards, to what lies beneath and within, on and off planet. 


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Harriet Hawkins is professor of Geography at Royal Holloway, University of London and co-founder of the Centre for GeoHumanities. 

Flora Parrott is an artist and postdoctoral researcher on the European Research Council funded project Think Deep based in the Geography Department at Royal Holloway University London. The key focuses of the practice are interdisciplinary collaboration and undergrounds. flora.parrott@rhul.ac.uk / www.floraparrott.com