Night Matters—Why the Interdisciplinary Field of “Night Studies” Is Needed

Abstract

The night has historically been neglected in both disciplinary and interdisciplinary research. To some extent, this is not surprising, given the diurnal bias of human researchers and the difficulty of performing work at night. The night is, however, a critical element of biological, chemical, physical, and social systems on Earth. Moreover, research into social issues such as inequality, demographic changes, and the transition to a sustainable economy will be compromised if the night is not considered. Recent years, however, have seen a surge in research into the night. We argue that “night studies” is on the cusp of coming into its own as an interdisciplinary field, and that when it does, the field will consider questions that disciplinary researchers have not yet thought to ask.

Full text

Opinion
Night Matters—Why the Interdisciplinary Field of
“Night Studies” Is Needed
Christopher C.M. Kyba 1, 2, * , Sara B. Pritchard 3, A. Roger Ekirch 4, Adam Eldridge 5,
Andreas Jechow 1, 2, * , Christine Preiser 6, Dieter Kunz 7, Dietrich Henckel 8, Franz Hölker 2,9 ,
John Barentine 10, 11 , Jørgen Berge 12, 13, Josiane Meier 8, Luc Gwiazdzinski 14 ,
Manuel Spitschan 15, 16, 17 , Mirik Milan 18, Susanne Bach 19 , Sibylle Schroer 2and Will Straw 20
1GFZ German Research Centre for Geosciences, Potsdam 14473, Germany
2Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin 12587, Germany;
hoelker@igb-berlin.de (F.H.); Schroer@igb-berlin.de (S.S.)
3Science and Technology Studies, Cornell University, Ithaca, NY 14850, USA; sbp65@cornell.edu
4Department of History, Virginia Tech, Blacksburg, VA 24061, USA; arekirch@vt.edu
5The School of Social Sciences, University of Westminster, London W1W 7BY, UK;
a.eldridge@westminster.ac.uk
6Institut für Sozialwissenschaften, Universität Augsburg, 86159 Augsburg, Germany;
christine.preiser@phil.uni-augsburg.de
7St. Hedwig-Hospital, 10115 Berlin, Germany; dieter.kunz@charite.de
8Institute for Urban and Regional Planning, Technische Universität Berlin, 10623 Berlin, Germany;
dietrich.henckel@tu-berlin.de (D.H.); josiane.meier@tu-berlin.de (J.M.)
9Institute of Biology, Freie Universität Berlin, 14195 Berlin, Germany
10 International Dark-Sky Association, Tucson, AZ 85719, USA; john@darksky.org
11 Consortium for Dark Sky Studies, University of Utah, Salt Lake City, UT 84112, USA
12 Faculty for Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, 9019 Tromsø,
Norway; jorgen.berge@uit.no
13 Centre for Autonomous Marine Operations and Systems Department of Biology, Norwegian University of
Science and Technology, 7491 Trondheim, Norway
14 Géographe, UniversitéGrenoble Alpes, 38100 Grenoble, France; lucmarcg@gmail.com
15 Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK;
manuel.spitschan@psy.ox.ac.uk
16 Centre for Chronobiology, Psychiatric Hospital of the University of Basel (UPK), 4002 Basel, Switzerland
17 Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel,
4055 Basel, Switzerland
18 VibeLab, Amsterdam, The Netherlands; Mirik@vibe-lab.org
19 Institut für Anglistik und Amerikanistik, Universität Kassel, 34125 Kassel, Germany;
susannebach@uni-kassel.de
20 Department of Art History and Communications Studies, McGill University, Montreal, QC H3A 0G4,
Canada; william.straw@mcgill.ca
*Correspondence: kyba@gfz-potsdam.de (C.C.M.K.); andreas.jechow@gmx.de (A.J.)
Received: 20 December 2019; Accepted: 9 January 2020; Published: 10 January 2020

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Abstract:
The night has historically been neglected in both disciplinary and interdisciplinary research.
To some extent, this is not surprising, given the diurnal bias of human researchers and the difficulty of
performing work at night. The night is, however, a critical element of biological, chemical, physical,
and social systems on Earth. Moreover, research into social issues such as inequality, demographic
changes, and the transition to a sustainable economy will be compromised if the night is not considered.
Recent years, however, have seen a surge in research into the night. We argue that “night studies” is
on the cusp of coming into its own as an interdisciplinary field, and that when it does, the field will
consider questions that disciplinary researchers have not yet thought to ask.
J2020,3, 1–6; doi:10.3390/j3010001 www.mdpi.com/journal/j

J2020,32
Keywords: night; night science; night studies; nyctology; interdisciplinary studies
1. Introduction
At any given moment, half of the Earth’s surface experiences night (Figure 1). The night is
not only a time, but in many respects a place: nocturnal environments are critical habitats for both
humans and other forms of life. Over the past 150 years, the night has undergone a series of major
transformations. Electrification, industrialization, and capitalism have altered humanity’s experiences
with night as both a time and place. Ecological studies demonstrate that these changes have also
affected nonhuman species (e.g., [
1
,
2
]). In 1978, Melbin’s pioneering article, “Night as frontier” sought
to outline a sociology of the night [
3
]. Otherwise, scholarship on the night has been limited until
recently, and disciplinary boundaries have tended to hamper interdisciplinary analyses. We, therefore,
still remain in the dark when it comes to our understanding of night, despite the night’s importance to
natural and social processes.
J 2020, 3 FOR PEER REVIEW 2
Keywords: night; night science; night studies; nyctology; interdisciplinary studies
1. Introduction
At any given moment, half of the Earth’s surface experiences night (Figure 1). The night is not
only a time, but in many respects a place: nocturnal environments are critical habitats for both
humans and other forms of life. Over the past 150 years, the night has undergone a series of major
transformations. Electrification, industrialization, and capitalism have altered humanity’s
experiences with night as both a time and place. Ecological studies demonstrate that these changes
have also affected nonhuman species (e.g., [1,2]). In 1978, Melbin’s pioneering article, “Night as
frontier” sought to outline a sociology of the night [3]. Otherwise, scholarship on the night has been
limited until recently, and disciplinary boundaries have tended to hamper interdisciplinary analyses.
We, therefore, still remain in the dark when it comes to our understanding of night, despite the night’s
importance to natural and social processes.
The challenges facing our planet and humanity during this century often have direct and indirect
connections to the night that must not be overlooked. There is, therefore, a pressing need for
interdisciplinary research into the night to come of age, expanding into a recognized field, because
the night matters.
Figure 1. At any given moment, half of the Earth’s surface experiences night. Data by NASA Blue
Marble and Black Marble, via John Walker ‘s webtool “Earth and moon viewer” [4].
2. The Night as an Interdisciplinary Research Challenge
We are a group of researchers and practitioners from diverse backgrounds in the natural and
social sciences, humanities, and non-governmental organizations (NGOs), united by our common
interest in the night (Table A1). There has historically been a lack of balance between investigations
into processes that occur during night versus day, from disciplinary, and especially interdisciplinary
perspectives. Humans are diurnal, and it is difficult to conduct research at night, regardless of
disciplinary specialization [2]. Moreover, as most people (including scholars) sleep at night, nocturnal
processes and issues are easily overlooked. There are also intellectual and institutional reasons for
our limited knowledge about the night. Research on the night is generally fragmented and siloed.
Disparate topics too often appear as “someone else’s problem” or are considered only as a facet of
Figure 1.
At any given moment, half of the Earth’s surface experiences night. Data by NASA Blue
Marble and Black Marble, via John Walker ‘s webtool “Earth and moon viewer” [4].
The challenges facing our planet and humanity during this century often have direct and indirect
connections to the night that must not be overlooked. There is, therefore, a pressing need for
interdisciplinary research into the night to come of age, expanding into a recognized field, because the
night matters.
2. The Night as an Interdisciplinary Research Challenge
We are a group of researchers and practitioners from diverse backgrounds in the natural and
social sciences, humanities, and non-governmental organizations (NGOs), united by our common
interest in the night (Table A1). There has historically been a lack of balance between investigations
into processes that occur during night versus day, from disciplinary, and especially interdisciplinary
perspectives. Humans are diurnal, and it is difficult to conduct research at night, regardless of
disciplinary specialization [
2
]. Moreover, as most people (including scholars) sleep at night, nocturnal
processes and issues are easily overlooked. There are also intellectual and institutional reasons for

J2020,33
our limited knowledge about the night. Research on the night is generally fragmented and siloed.
Disparate topics too often appear as “someone else’s problem” or are considered only as a facet of
another field, thereby making interdisciplinary inquiry fundamentally difficult. This fragmentation and
the lack of the “professionalization” of night studies as a field to date hamper raising the appropriate
questions, let alone finding solutions. In Donald Rumsfeld’s famous framing [
5
], there remain many
“unknown unknowns” with respect to the night.
A pressing “nighttime” problem, for example, is growing concern over mismatches between social
and biological time in humans. The 2017 Nobel Prize in Physiology and Medicine was awarded for the
discovery of the molecular mechanisms in nearly all living organisms that govern circadian rhythms,
ranging from activity patterns to blood pressure. The timing of many common human behaviors
is often no longer aligned with these biological clocks, and there is ample concern that widespread
insufficient or ineffective sleep [
6
] is detrimental to health. Sleep, however, is not simply a medical
issue that can be isolated from broader social, cultural, and economic change. There are complex
causes of changes in human sleep patterns over the past 150 years [
7
]. The development and expansion
of artificial light at night has played a central role, with most cities now brightly illuminated [
8
,
9
].
Beyond lighting, factors such as incessant processes in industrial plants, connectivity across time zones,
provision of 24/7 services including energy, security, and health care, and the possibility of constant
technological connectivity in both professional and personal domains have expanded many human
activities beyond previous temporal limits (e.g., [10]).
Extending the hours of labor for non-essential services, to take but one example, both reflects
and reinforces industrial capitalism [
11
]. Nighttime shifts that enable factories to raise profits for
shareholders often pay more than equivalent day shifts. This financial incentive, in turn, often attracts
workers who are economically marginal including many women, people of color, and immigrants.
Despite increased compensation, the nighttime economy may end up worsening social and economic
inequality and magnifying environmental injustice, for instance, if these groups end up suffering from
higher rates of disease and poorer health. There are also social costs due to incongruities between
the schedule of workers and those of their families. One may question whether night economies
really raise local revenue, once sleep deficits and the healthcare costs of night shift workers are also
considered. This example demonstrates how night is an “interdisciplinary object”; physical and social
processes at night—circadian rhythms, capitalism, education, race, gender, security, mobility, public
lighting, and inequality—are entangled in complex and sometimes unexpected ways.
Now-established interdisciplinary fields such as gender studies and environmental studies provide
precedents for the kind of professionalization and institutionalization of research that we envision. Like
the environment, the night is an especially broad topic that invites diverse perspectives. Furthermore,
night studies scholars have already drawn from a wide range of humanities, social science, and natural
science disciplines. Due to the complexity of the night, it is essential to establish deep collaboration
among social scientists, natural scientists, and humanists that unites empirically-based understandings
of physical or biological processes with similarly empirically-grounded understandings of cultural,
social, and historical processes (c.f. [
12
]). Complex social problems are unlikely to be easily fixed
by technoscientific “solutions”. For example, therapy based on applied understanding of the “night
hormone” melatonin could not solve the sleep crisis on its own.
Failing to consider the full interdisciplinary context of night has already affected real-world
situations. Consider the recent replacement of outdoor lighting in Rome in 2017 [
13
]. The city’s
lighting transition was undertaken within the frame of energy consumption and cost, and resulted
in the replacement of existing warm color lamps with “colder” white LED lighting. Missing from
consideration in the policy decision were public expectations and the cultural meaning of urban light,
as well as the negative environmental side effects of broad spectrum (white) light [
13
]. As a result,
residents and tourists had strong negative reactions to the light, arguing that the ancient city should
not be lit with cold, harsh white lighting [
14
]. In addition, in trying to address one environmental
problem (climate change), Rome may have worsened another (light pollution) in the process.

J2020,34
We suggest that an interdisciplinary approach to night governance that incorporates cultural,
economic, environmental, and other concerns would yield solutions to nighttime problems that avoid
public backlash, negative impact on tourism, and wasted budget due to reversal of policy (e.g., [
15
]).
Given the broad changes that the night has experienced in recent decades, the quickly spreading
recognition of the value of “night mayors” in cities including Amsterdam, London, and New York
City [
16
], and the growing concern over “loss of the night” caused by artificial illumination and shifting
schedules, a multi-faceted approach to night as an integrated field of study will redound to the public
welfare as well as deepen our knowledge of this critical realm of everyday existence.
Organizations such as institutes, university departments, and research clusters have been
established to bring interdisciplinary focus on places (e.g., oceans, polar areas, and area studies), topics
(e.g., migration and transportation), and even times (e.g., history). It is, therefore, in some sense
surprising that a similar organization has not yet been founded to address the night. Momentum
seems to be building in this direction, however. For example, the Consortium for Dark Sky Studies
recently established a new undergraduate minor in “dark sky studies” at the University of Utah.
Gaston recently made a compelling case in The American Naturalist for why “nighttime ecology” must
be established as a synthetic program of research in this scientific field [
17
], and Shaw has argued
for “nightology”, proposing an integrated approach to nocturnal urban research [
11
]. While these
are exciting developments, we suggest that the emerging field of night studies must necessarily be
much broader.
Beyond advancing interdisciplinary knowledge of the night, we expect that night studies
researchers will, in many cases, work closely with organizations on evolving challenges such as
those related to night governance, sustainability, or a carbon-free economy. Ideally, knowledge transfer
from night studies scholars to practitioners will help them address emerging challenges, rather than
responding to them after the fact.
An example of an interdisciplinary challenge for cities where night studies scholars could provide
expertise is in the provision of public transit during the night. Night transit serves diverse publics,
who surely have different expectations for service and perceptions of safety (e.g., a group of young
men heading to a nightclub versus a female, first-generation immigrant nurse returning home alone
after working an evening shift). Lobbies for late night transit often include the entertainment industry,
while taxi companies, residents, and transit worker organizations are often against expanded night
services (e.g., [
18
]). From an economic perspective, night transit may provide benefits due to increased
activity, but impose future costs due to the health impacts of sleep loss by those using the service.
Furthermore, long commutes and lost sleep may increase overall social inequality within a region [
19
].
Without a full picture, governance of the night may therefore serve the interests of a select powerful
group, rather than the community generally.
3. Conclusions
The night has experienced major changes in recent decades, and the pace of change is unlikely
to slow down. While research into the night has expanded greatly in recent years, we believe that
further networking and institutionalization is urgently needed. In order to develop into a recognized
interdisciplinary field, night studies will need to see the establishment of journals, conference series,
dedicated funding lines, research institutes, and university departments offering programs of study. If
the field develops as we hope it will, perhaps it may eventually become recognized by the Greek term
“nyctology”: the study of night matters.
4. Addendum
Note that another opinion on the “science of the night” with a different focus was recently
published by Michele Acuto [
20
]. We agree strongly with Michele Acuto, and encourage readers to
also read his piece. This manuscript was drafted independently over a period of in-person and online
meetings spanning from 2017–2019, without any correspondence with Michele Acuto.

J2020,35
Author Contributions:
A.J., C.C.M.K., D.H., F.H., J.M., and S.S. initiated the project, and selected and invited the
rest of the co-authors to contribute. All authors collaborated on developing the outline and choosing specific
examples or case studies via electronic and in-person meetings. Multiple drafts of the opening paragraph were
written by co-authors, and ranked by all authors to select an initial opening. S.B.P. wrote the first complete draft of
the paper, and all authors critiqued this draft. A.J., A.E., C.C.M.K., C.P., D.H., F.H., J.M., and S.S. edited subsequent
drafts. C.C.M.K coordinated the project and was the primary editor. All authors critiqued draft versions of
the manuscript and approved the final version. All authors have read and agreed to the published version of
the manuscript.
Funding:
C.C.M.K. acknowledges funding from the European Union’s Horizon 2020 research and innovation
program under grant agreement no. 689443 via project GEOEssential, and funding from the Helmholtz Association
Initiative and Networking Fund under grant ERC-RA-0031. S.P.’s current research is supported by the U.S.
National Science Foundation’s Program in Science, Technology, and Society (grant no. 1555767). A.J. and F.H.
are supported by the ILES project funded by the Leibniz Association, Germany (SAW-2015-IGB-1). S.S. and F.H.
acknowledge the support of the STARS4ALL CAPSSI project funded by the European Union H2020 Programme
(688135).
Acknowledgments:
We thank Dieter Lang from LEDVANCE for critical comments on early drafts of the
manuscript. The publication of this article was funded by the Open Access Fund of the Leibniz Association.
Conflicts of Interest:
The authors declare no conflict of interest. The funders had no role in the design of the
study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to
publish the results.
Appendix A
Table A1. Areas of main activity of the authors.
Area Field Name
Humanities
Cultural studies Will Straw
History A. Roger Ekirch
Literature & gender studies Susanne Bach
Natural sciences
Chronobiology Dieter Kunz
Ecology Franz Hölker
Ecology/arctic night Jørgen Berge
Physics Christopher Kyba
Physics/engineering Andreas Jechow
Visual Neuroscience Manuel Spitschan
NGOs International Dark-Sky Association John Barentine
Night mayor of Amsterdam 2012–2018 Mirik Milan
Science communication Sibylle Schroer
Social sciences
Geography Luc Gwiazdzinski
Planning Dietrich Henckel
Planning Josiane Meier
Science and technology studies Sara Pritchard
Sociology Christine Preiser
Sociology/night economy Adam Eldridge
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