Abstract:

Light pollution is the human-made alteration of outdoor light levels from those occurring naturally (DarkSky International - darksky.org), caused by the excessive or inappropriate use of artificial light at night, with a negative impact in the night sky, in biodiversity and in human health. The Milky Way is hidden to more than one-third of humanity (Falchi et al. 2016). Satellite images indicate that light at night increased by a global average of about 2$\%$ per year (Kyba et al. 2017), and in the last decade the brightness of the sky at night increased by an average of 10$\%$ per year (Kyba et al. 2023). \\ We present the first results of a study of light pollution in the night skies of Uruguay, started in the Capital city and the Eastern region at the beginning of 2023. We analized the time evolution of the sky brightness from Unihedron SQM LU-DL and LE measurements taken every 5 minutes during at least 2 months. We also survey illuminance, color temperature, location, design and technology of the outdoor luminaires in each location.\\ The study in Montevideo is financed by the Municipality as part of a project between this institution and our university. The coordination between the Technical Unit of Public Lighting of the Municipality of Montevideo and the astronomy and biology researchers is in charge of Andrés Olivera (FCIEN - UdelaR). With support from PEDECIBA and the PDU of Physical Sciences of CURE we instaled SQMs at the astronomical observatory, at CURE, and in rural and mountainous areas of Rocha. We are also evaluating these last sites as potential dark sky places where the night sky will be valued as an environmental, scientific, cultural and landscape heritage, and where the darkness of the night sky must be preserved through the regulation of outdoor lighting.

Abstract:

Light pollution is a form of environmental degradation that is increasing worldwide and affects the natural environment, flora, fauna, and various aspects of human life. Despite the growing concern about this issue, its study is still limited in Latin America. In this study, we conducted a comprehensive analysis of the expansion of nighttime artificial light in the major urban centers of Latin America between 2012 and 2022. The study focused on cities including Mexico City, São Paulo, Bogotá, Lima, Santiago de Chile, Buenos Aires, Brasilia, Caracas, San José, Havana, Quito, Asunción, Montevideo, and La Paz. This study provides valuable information about the growing threat of light pollution in Latin America and supports the need to take measures that help control the associated environmental degradation. Raising awareness about the negative impacts of light pollution on the ecosystem, human health, and astronomical observations is crucial. Implementing lighting regulations, promoting energy-efficient lighting technologies, and incorporating considerations about light pollution in urban planning are essential steps to mitigate the effects of light pollution and protect the natural environment in the major urban centers of Latin America.

Abstract:

Increasing the emission of artificial light at night has well-documented negative effects on the quality of natural dark skyes and changes the natural light/dark cycles, on which many species depend. Dark skies are relevant as natural values and for their cultural and heritage significance. This issue is just beginning to be perceived as a problem by decision makers and the civil society. The present work is a response to the concern of residents of Las Brujas (Canelones, Uruguay) regarding public lighting installation in July 2022. This research analyzes the nocturnal landscape before and after the placement of public lighting and its impact over the natural soundscape. Soundscapes are defined as the set of sounds generated by the elements that compose an environment. Through soundscapes analysis, it is possible to estimate the response of organisms to anthropogenic pressures and to account for the structure and dynamics of the environment. For analyzing the nocturnal landscape, the sky brightness was measured at impact and control sites using an SQM photometer. From measurements obtained at 17 sampling points, sky brightness maps before and after the impact were made. For the analysis of the soundscapes, a Before-After, Control-Impact sampling design was implemented. A passive acoustic monitoring (PAM) was carried out, in which the soundscapes of 5 sites (1 impacted site and 4 control sites) were recorded before and after the implementation of the new public lighting. By performing an analysis of variance, significant differences were found in the sky brightness before and after the public lighting was operational. However, the analyzed acoustic data shows that there are no significant variations in the acoustic landscape despite the alteration of the nocturnal landscape. Hypotheses that can explain this phenomenon are discussed and recommendations for the management of the socio-environmental problem are proposed.

Abstract:

Light pollution is an anthropogenic phenomenon that has grown exponentially in recent years due to the improper use of the rapidly evolving lighting technologies. All this unnecessary and misdirected light is causing detrimental effects on astronomy, ecology, human health, among others. The phenomenon is ubiquitous, but not systematic studies have been reported in Colombia, a country with a growing astronomical community and with the highest biodiversity in the world. In this study, we present the first characterization of the quality of Colombian skies from sites of astronomical and ecological interest. Using all-sky photometric data, we obtained the first quantitative estimates of Night Sky Brightness and Correlated Color Temperature from the Tatacoa Desert (the only Starlight Destination in Colombia), the Observatory of the Technological University of Pereira, the Bogotá Botanical Garden and the Guadalupe Hill in Bogotá. Finally, our data were compared with similar sites in Latin America and/or the world. The data also represents an effort to contribute to the protection of the sky, a heritage that we must protect and preserve.

Abstract:

In 2021, the LSST Discovery Alliance (LSST-DA; formerly known as the LSST Corporation) launched a unique, cross-disciplinary postdoctoral fellowship to help the scientific community prepare for and make excellent early use of data from Rubin Observatory’s Legacy Survey of Space and Time (LSST). The LSST-DA Catalyst Fellowship funded by the John Templeton Foundation was designed to accelerate ground-breaking scientific discoveries, and to impact the field of astrophysics beyond the research of the Catalyst Fellows. It strives to create and support diverse networks as learning systems that benefit a wide range of participants: Fellows, their advisors, their host departments, teams of mentors, and the broader astrophysics community. Key aspects include: (i) participation of social scientists both as Fellows and on the Steering Committee; (ii) the selection of Fellows committed to producing community impacts beyond the publication of scientific findings and service as ambassadors for the use of Rubin LSST data at their host institutions; (iii) the award of a Fellowship each year to an astrophysicist hosted at an Expansion Site, which is typically a small, under-resourced, or predominantly minority-serving institution currently outside of LSST-DA membership; and (iv) mentoring committees for each Fellow that include the Fellow’s local advisor, an active member of one of the LSST Science Collaborations, a researcher involved in the creation of LSST analysis tools, a faculty member from an Expansion Site, and a social scientist. In the first two years of the Fellowship, LSST-DA recruited 14 Catalyst Fellows – 12 in astrophysics and 2 in the social sciences. This contribution reports on experiences of direct participants – Fellows, Steering Committee members, and mentoring committees – during the development and pilot phases of the Fellowship.