Elsewhere, elsewhen: planetary analogues as time machines

clemens finkelstein

Summary: From a dynamited Arizona cinder field to a sealed Houston habitat, planetary analogue sites manufacture time, suppressing Indigenous histories to rehearse speculative futures in a revealing act of temporal asymmetry.

Cratering the present

From 1967 to 1968, the United States Geological Survey (USGS) dynamited a corner of Arizona into the Moon (Fig. 1). Between 28-31 July 1967, on a black cinder field northeast of Flagstaff, engineers buried hundreds of explosive charges and detonated them in carefully staged sequences, excavating 47 craters whose sizes and positions replicated, at a 1:1 scale, a patch of the Sea of Tranquillity recently photographed by NASA’s Lunar Orbiter programme (1966-1967) to select the most suitable landing site for Apollo 11 in 1969 (Figs. 2-3). A second round that October brought the count to 143 craters, and, in 1968, a larger field of several hundred craters was blasted nearby.[1] The detonations were layered in time as well as space: astrogeologically determined ‘old’ craters were blasted first, then partially buried; ‘intermediate’ and ‘young’ craters followed, so that the finished field would display a fabricated stratigraphy.[2] Millions of years of meteorite bombardment were compressed into a few days of anthropogenic demolition work. Astronauts in pressure suits then trudged across the Cinder Lake Crater Field, rehearsing traverses they would later perform 250,000 miles (400,000 km) away.

Cinder Lake is an early and unusually literal specimen of a now-global practice: the planetary analogue. Planetary analogues are sites on Earth that are made to stand in for extraterrestrial environments such as the Moon, Mars and the icy moons of the outer planets. Some of these surrogate sites may be found in deserts, lava fields and meteorite-impact craters, or in polar deserts whose geology or chemistry resembles that of another world, enabling scientists to test instruments and rehearse the search for extraterrestrial life. Others are built as sealed habitats and isolation chambers in which crews experience the confinement of voyages that have yet to leave Earth. Either way, the scientific literature treats the analogue predominantly as a spatial surrogate: a stand-in for somewhere else.[3]

But look again at what the engineers produced at Cinder Lake. Beyond just a model of a place, they built a model of its environmental history. The craters were blasted in sequence to fake a stratigraphy, old before young, so that the field would read as the outcome of an aeon of meteorite bombardment. They forged a temporal order as much as a geographical one. The spatiotemporal forgery even demanded a second – quieter yet no less violent – operation that erased the Indigenous communities that had once inhabited these lands and whose oral traditions still carry the story of the 11th-century eruption of Sunset Crater Volcano that buried the basin in the black cinders the USGS would one day blast into a replica Moon.[4] They and their descendants then had to be subtracted so that another world’s deep past could take their place. The site gave up – or more accurately, was made to give up – its own time to host another world’s.

This is the structural pattern I want to track here. Planetary analogues are not, in the end, merely machines for simulating space; they are machines for constructing time. Each one repeats the same three operations visible at Cinder Lake: import an alien past, rehearse a speculative future and suppress the local present that stands in its way. Further, these operations run essentially in one direction. The terrestrial site gives; the planetary referent takes; nothing returns. Whereas discussions of the analogue trade chiefly on its spatial symmetry, I want to trace its temporal asymmetry to read planetary analogues as time machines obscured by staging visual resemblance.

Elsewhere: the allotopic environment

When astrogeologists study the Haughton impact crater on Devon Island or the hyperarid soils of Chile’s Atacama as proxies for Mars, the claim is as temporal as it is spatial (Fig. 4). Once upon a time, roughly four billion years ago, Mars, the reasoning runs, contained liquid water, a denser atmosphere and perhaps the conditions for life. Earth retains environments that resemble the vanished Martian world. The analogue site therefore functions as a window looking both onto another place as well as that distant planet’s past, a fragment of alien deep time conveniently preserved in our own backyard.[5]

This is a remarkable historiographical manoeuvre in which analogue scientists play historian. They select a surviving trace, argue for its representativeness and use it to reconstruct an inaccessible elsewhen. The difference, however, is one of scale and direction. Where the historian reads a 16th-century notarial register as a trace of its own past, the analogue scientist reads a Devonian lakebed as a trace of somewhere else’s. A past belonging to a different world entirely.

Dipesh Chakrabarty has argued that the recent planetary turn obliges historians to think human-scale and geological-scale time together.[6] The analogue radicalises that demand. It asks us to braid Earth’s geological time with that of another planet at a single terrestrial site. The analogue relation draws temporal meaning out of the terrestrial site and exports it elsewhere.

Elsewhen: the allochronic environment

In 1983, the anthropologist Johannes Fabian published a critique that stung. Time and the Other argued that Western anthropology systematically denied coevalness to the peoples it studied. Fieldwork demanded shared time – sitting, talking and eating in a common present – yet the resulting monographs cast their subjects as primitive, traditional and premodern inhabitants of an earlier epoch. Fabian named this discursive expulsion from the shared present allochronism: the Other was not merely elsewhere; the Other was elsewhen.[7]

What happens when we extend Fabian’s critique from peoples to places? Consider Devon Island. To the Inuit of Nunavut, it is Tallurutit (Inuktitut: ᑕᓪᓗᕈᑎᑦ), a name said to liken the streaks across the island’s landscape to the tattooed lines of Inuit women’s chins. In English-language reference works, it is the world’s largest uninhabited island, a polar desert in the Canadian High Arctic. Uninhabited is doing suspicious work in the preceding sentence. Archaeological traces of human presence on the island reach back about 4000 years. At Dundas Harbour, the stone remains of a Thule settlement some thousand years old sit within walking distance of a Royal Canadian Mounted Police outpost established in 1924 to assert Arctic sovereignty. A post sustained in the 1930s by Inuit families relocated, disastrously, from Baffin Island, and abandoned in 1951.[8] The island holds these histories in its permafrost. Yet since 1997, it has been something else: Mars.

The NASA Haughton–Mars Project (HMP) operates from the rim of a 23-kilometre impact crater punched into the island around 31 million years ago. For several million years thereafter, the crater held a lake, ringed by boreal forest and home to early seal relatives.[9] Now cold, dry, rocky, windswept and barely vegetated, the crater is routinely described as one of the most Mars-like places on Earth (Fig. 5). Analogue astronauts rehearse spacewalks across its floor, and a winding gully has even been rechristened Astronaut Canyon.[10]

For the analogue to function, Devon Island’s own time must be evacuated: 4000 years of Inuit and pre-Inuit presence, the colonial archive of the RCMP post, the living political present of Nunavut. All of it becomes static in the signal. The landscape, instead, is recast as pre-human. A ready-made fragment of Mars, which is to say, of a world where (human) history has never happened. This is allochronism applied to terrain. Where Fabian’s anthropologists consigned living peoples to the past, the analogue consigns storied landscapes to a condition outside terrestrial history altogether, so that they may serve as blank pages for an extraterrestrial narrative.

And here the temporal asymmetry bites hardest, because the exchange is lopsided. Devon Island lends Mars its surface, its light, its loneliness; in return, it is given a description – uninhabited, barren, Martian – that quietly overwrites everyone who has ever lived there. The island is a palimpsest thick with inscribed time. A single sweep of the eyes across that crater encompasses the Oligocene impact, the Miocene lake, the thousand-year-old Thule dwelling, the abandoned colonial post and the rehearsed Martian future. None of them is synchronous with the others; all of them are present at once. This is a condition that the historian Reinhart Koselleck describes as ‘the contemporaneity of the non-contemporaneous’, in which every place is a sediment of layered, non-simultaneous times.[11] The analogue site is perhaps the purest laboratory specimen exemplifying his insight. Miocene crater, Thule ruin, colonial outpost and rehearsed Martian future stacked in a single field of view. The planetary analogue, however, unlike the historian, acknowledges only one layer and relegates the rest to a state of interference.

Chronotechnics

So far, the analogue has trafficked in pasts both borrowed and buried. Its third temporal commodity is futurity, where architecture takes over from geology. At the Johnson Space Center in Houston stands Mars Dune Alpha, a habitat of roughly 160-square-metres designed by BIG–Bjarke Ingels Group and 3D-printed by ICON from a concrete-like material, in which successive volunteer crews of NASA’s Crew Health and Performance Exploration Analog (CHAPEA) programme have lived for 378 days at a stretch, pretending to be on Mars (Fig. 6). The pretence is built, not merely imagined, and what is built is mostly time. Programmable lighting manufactures a day where the Texan sun is sealed out. Communications with the outside world are artificially delayed by up to 22 minutes each way, because that is how long radio signals take to crawl between Mars and Earth. Astronomical distance is simulated through the medium of time. Even the floor plan stages temporality, grading the interior from private sleeping quarters through shared galley to workstations: personal time, social time, mission time. All these temporal dimensions are zoned in plywood and printed concrete.

I want to call such infrastructural enactment a chronotechnics: an architecture whose primary product is a temporal regime.[12] The planetary analogue thus joins a long lineage from the medieval monastery that disciplined the day into liturgical hours to the industrial factory that disciplined it into shifts to the prison that made timetables into walls.[13] The analogue habitat, however, adds a twist none of its forebears attempted in that the time it imposes does not yet exist. The monastery enforced religious time and the factory that of capitalism, both times of the present. Mars Dune Alpha enforces the daily rhythm of a Martian settlement that has never been built, may never be built, and whose actual texture nobody can know for certain. Its inhabitants live inside an architectural conjecture: Ernst Bloch’s ‘not-yet’ (Noch-Nicht) poured in concrete.[14]

The deepest confirmation that the planetary analogue’s medium is time came from an experiment that abolished landscape entirely. Mars-500 locked six male participants inside a modular, windowless complex on the outskirts of Moscow for 520 days, from 2010 to 2011, to simulate a round trip to Mars. The study was conducted by the Institute of Biomedical Problems (IBMP) of the Russian Academy of Sciences, in collaboration with the European Space Agency (ESA) and the China Manned Space Agency (CMSA). There was no red sand standing in for Martian regolith, no horizon, nothing Mars-like in sight. What the crew endured instead was pure duration: the transit time, the communication lag, the slow accumulation of confinement and isolation. Strip away the scenery and the simulation loses nothing essential, because the scenery was never the point. You can simulate Mars without reproducing a single square metre of its surface. You cannot simulate it without reproducing its time.

There is a paradox coiled inside all this rehearsal, and the historical theorist Zoltán Boldizsár Simon has devoted several books to its components. His early account of the unprecedented sets the trap: the planetary analogue exists to prepare for an event whose defining property is that nothing can prepare for it.[15] A first descent onto Mars would be, in his terms, a rupture without precedent. And rehearsing the unprecedented seems a contradiction. The analogue manages the contradiction by manufacturing precedents: by generating, in the present, a synthetic past for a future that has not happened. Simon’s more recent work suggests why this is more than a curiosity of spaceflight. In The Fabric of Historical Time (2023), written with Marek Tamm, the authors distinguish temporality from historicity and describe historical time as a fabric in which many temporalities and historicities coexist, overlap and clash rather than a single trajectory.[16] The analogue site is a place where that fabric is deliberately torn: a single thread of it, the speculative Martian future, is drawn forward while the rest are cut away. In Plurihistoricity (2025), Simon fittingly argues that contemporary societies no longer inhabit one shared regime of historical change but several conflicting regimes at once, among which he counts the technological dream of expansion into space alongside the prospect of extinction and the unfinished reckoning with colonial injustice.[17] The planetary analogue is where two such regimes meet on the same ground: the colonial pattern of clearing land of its inhabitants, now performed in the service of a spacefaring future.[18] Devon Island and the Cinder Lake fields are more than mere simulations of other worlds; they are sites where incompatible histories are forced into a single plot.

This is why the rehearsal leaves a residue in the participants. When the first crew someday descends to the actual Martian surface, they will meet it partly as a repetition of Devon Island, of the Atacama, of a dynamited cinder field in Arizona. The pre-furnishing is not only institutional but felt. Reflecting on the halfway point of being sealed inside Mars Dune Alpha for a year, the CHAPEA commander Kelly Haston remarked: ‘I actually apparently really love being on Mars’.[19] The hedge in that sentence — ‘apparently really’ — registers the strangeness by which an affection is borne for a Mars one has never visited (and may never), through a place that is, essentially, a printed sandbox in Houston. This is what the planetary analogue finally produces. More than anticipating the future, it pre-furnishes the future with memories of surrogate experiences.

Temporal asymmetry: a preliminary sketch

The concept of temporal asymmetry is established in the philosophy of physics, where it denotes the structural differences between our relations to the past and the future: we remember one but not the other, causes precede effects, and entropy increases.[20] In historical theory, the phrase appears only fleetingly, and the relation I give it – a lateral, unidirectional transfer of temporal identity between places – has not, to my knowledge, been isolated as such.[21] In the above sketch of temporal asymmetry produced by planetary analogues, a site is conscripted to carry another’s past or future; traffic runs in one direction, and the subordinate site pays for the privilege by suppressing its own historical time. Elsewhere is made to stand for elsewhen.

So why should historians care about a concept distilled from such a peculiar practice? Because the planetary analogue is a diagnostic caricature of the historical method. Every act of historical comparison performs a miniature analogue operation. Periodisation, comparison, and the denial of coevalness are all temporal transfers, and most are asymmetric. The planetary analogue simply performs the transfer with bulldozers and dynamite at a scale and literality that make the operation impossible to overlook. It is a temporal machine twice over: a machine that manufactures time for its users and a machine that reveals to attentive historians the time-manufacturing embedded in our own most routine procedures. The analogue does to a cinder field what every history does to its sources; it simply leaves the evidence lying in the open.

That visibility comes with an obligation that the concept must confront. If temporal asymmetry names a unidirectional transfer in time, then an analysis content to describe it from the outside risks reproducing the trajectory it set out to critique: narrating other places’ conscription in the same extractive grammar that it diagnoses. Whether temporal asymmetry can be thought from elsewhere, through epistemologies of time other than the Western historicist approach this sketch has assumed, is the question on which its critical purchase ultimately depends.[22] I am unable to settle this here. Nevertheless, the planetary analogue itself offers a clue, because the asymmetry it enacts is never complete. Somewhere northeast of Flagstaff, the craters blasted in 1967 and 1968 to rehearse the 1969 Moon landing are still faintly visible, softened by half a century of Arizona weather (Fig.7). A fake lunar landscape slowly becoming an authentic Earthly ruin, acquiring at last a past that is genuinely its own. Landscapes, it turns out, may resist permanent conscription into other worlds’ chronologies. Histories seep back. If the planetary analogue is a machine for sending places elsewhere in time, then the task it sets the historian is to tend the seepage, and to restore coevalness to the places we sent elsewhen.

[Published 21.7.2026 
temporal dis:connectivity is a blog series that explores how concepts and experiences of time shape global processes across time and space. In this series, scholars from different disciplines ask what attention to temporality can reveal about globalisation, historical change, and the ways societies imagine the past, present, and future.
For the previous entry in this series on temporal dis:connectivity, click here. To read the introduction to the series, click here.]

[1] On the construction and crater counts, see ‘Cinder Lakes Apollo Training Area History’, Forest Service, US Department of Agriculture, 2026, accessed 24 June 2026, https://www.fs.usda.gov/r03/coconino/recreation/discover-history/cinder-lakes-apollo-training-area-history; R. Greg Vaughan et al., Walk in the footsteps of the Apollo astronauts: a field guide to northern Arizona astronaut training sites, ed. Philip A. Pearthree, vol. 55, Field Guide, (Boulder: Geological Society of America, 2019).

[2] Paul Sweitzer, Paul Sweitzer Collection (Flagstaff: Cline Library, Northern Arizona University, 1979), NAU.PH.426.

[3] See F. Foucher et al., ‘Definition and use of functional analogues in planetary exploration’, Planetary and Space Science 197, no. 105162 (2021) 10.1016/j.pss.2021.10516; Louisa J. Preston and Lewis R. Dartnell, ‘Planetary habitability: lessons learned from terrestrial analogues’, International Journal of Astrobiology 13, no. 1 (2014); Richard Léveillé, ‘A half-century of terrestrial analog studies: from craters on the Moon to searching for life on Mars’, Planetary and Space Science 58, no. 4 (2010); Sheryl L. Bishop, ‘From Earth Analogues to Space: Learning How to Boldly Go’, in On Orbit and Beyond: Psychological Perspectives on Human Spaceflight, ed. Douglas A. Vakoch (Berlin: Springer, 2013).

[4] Mark D. Elson, ed., Sunset Crater Archaeology: The History of a Volcanic Landscape, vol. 37, Anthropological Papers (Tucson: Center for Desert Archaeology, 2011). See also Fernando Armstrong-Fumero and Julio Hoil Gutierrez, eds., Legacies of Space and Intangible Heritage: Archaeology, Ethnohistory, and the Politics of Cultural Continuity in the Americas (Boulder: University Press of Colorado, 2017).

[5] See Rafael Navarro-González et al., ‘Mars-Like Soils in the Atacama Desert, Chile, and the Dry Limit of Microbial Life’, Science 302, no. 5647 (2003).

[6] Dipesh Chakrabarty, The Climate of History in a Planetary Age (Chicago: University of Chicago Press, 2021).

[7] Johannes Fabian, Time and the Other: How Anthropology Makes Its Object (New York: Columbia University Press, 1983). For a critique that extends and complicates Fabian’s argument, see Kevin Birth, ‘The creation of coevalness and the danger of homochromism’, Journal of the Royal Anthropological Institute 24, no. 1 (2008).

[8] Shelagh D. Grant, Polar imperative: a history of Arctic sovereignty in North America (Vancouver: Douglas & McIntyre, 2010).

[9] Natalia Rybczynski, Mary R. Dawson and Richard H. Tedford, ‘A semi-aquatic Arctic mammalian carnivore from the Miocene epoch and origin of Pinnipedia’, Nature 458, no. 7241 (2009).

[10] Pascal Lee, ‘Mars on Earth: The NASA Haughton-Mars Project’, Ad Astra May-June (2002).

[11] Reinhart Koselleck, Sediments of Time: On Possible Histories, trans. Sean Franzel and Stefan-Ludwig Hoffmann (Stanford: Stanford University Press, 2018).

[12] On Chronotechik (chronotechnique), see Wolfgang Ernst, Chronopoetics: The Temporal Being and Operativity of Technological Media, trans. Anthony Enns (London: Rowman & Littlefield, 2016).

[13] Michel Foucault, Discipline and Punish: The Birth of the Prison, trans. Alan Sheridan (New York: Pantheon, 1977). Henri Lefebvre, Rhythmanalysis: Space, Time and Everyday Life, trans. Stuart Elden and Gerald Moore (London: Continuum, 2004).

[14] Ernst Bloch, The Principle of Hope, trans. Neville Plaice, Stephen Plaice, and Paul Knight (Cambridge, USA: MIT Press, 1995). See also Alexander C.T. Geppert and Tilmann Siebeneichner, ‘”Lieux de l’avenir”. Zur Lokalgeschichte des Weltraumdenkens’, Technikgeschichte 84, no. 4 (2017).

[15] Zoltán Boldizsár Simon, History in Times of Unprecedented Change: A Theory for the 21st Century (London: Bloomsbury, 2019).

[16] Zoltán Boldizsár Simon and Marek Tamm, The Fabric of Historical Time (Cambridge: Cambridge University Press, 2023).

[17] Zoltán Boldizsár Simon, Plurihistoricity: On the Historical Cultures of Extinction, Justice and the Historical Profession (London: Routledge, 2025).

[18] See Katherine G. Sammler and Casey R. Lynch, ‘Apparatuses of observation and occupation: settler colonialism and space science in Hawai’i’, Environment and Planning D: Society and Space 39, no. 5 (2021) doi.org/10.1177/02637758211042374.

[19] Elisha Sauers, ‘This NASA crew has survived Mars for six months — sort of’, Mashable, 30 December 2024, https://mashable.com/article/nasa-chapea-mars-crew, last accessed: 24 June 2026.

[20] Paul Horwich, Asymmetries in Time: Problems in the Philosophy of Science (Cambridge, USA: MIT Press, 1987).

[21] The phrase surfaces in discussions of Arthur C. Danto’s narrative sentences and of the gap between agents’ forward-looking uncertainty and historians’ retrospective knowledge. See Jonas Grethlein, Experience and Teleology in Ancient Historiography: Futures Past from Herodotus to Augustine, trans. Experience and Teleology (Cambridge: Cambridge University Press, 2013).

[22] See Nancy D. Munn, ‘The Cultural Anthropology of Time: A Critical Essay’, Annual Review of Anthropology 21 (1992) doi.org/10.1146/annurev.an.21.100192.000521.

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