Since ancient times, agricultural planning has been related to celestial movements. Observing the cycles of the sun and moon has been a fundamental tool for deciding when to plant and harvest. However, today we know that the relationship between dark skies and agricultural production is even closer and that protecting the night skies from light pollution is key to food security.

For thousands of years, the indigenous peoples inhabiting the region have enhanced their agriculture through the observation of the stars. Despite not having current scientific knowledge, they identified how the Moon, the Sun, the stars, and planets influence the crops. This wisdom has been translated into agricultural-astronomical calendars that determine the different agricultural tasks according to lunar, solar cycles, and the influence of the stars.

One of the most notable manifestations of this tradition is the celebration of the Andean New Year, on June 21 each year, which coincides with the winter solstice, when the sun’s position is at the greatest distance from the southern hemisphere of the earth. For the indigenous peoples of the region, this period marks the end of the harvest season and the beginning of the new agricultural cycle.

Agriculture guided by the stars in Chile

These ancestral knowledge have been adopted in modern agriculture, in search of more sustainable production. During the first half of the 20th century, biodynamic agriculture emerged in the fields of Europe, as a response to industrialization and its negative effects on the fertility of seeds and crops.

Biodynamic agriculture, according to Demeter –an international organization that certifies this production method–, is based on the theories of Rudolf Steiner and considers the field as a living organism, where all the elements required for production come from the same field.

This method also takes into account the influence of the stars on agricultural tasks, using tools such as the biodynamic calendar. This calendar, similar to the calendars created long ago by indigenous peoples, divides the days according to the position of the moon and constellations, guiding activities such as planting, harvesting, pruning, and even compost preparation.

In Chile, in 2023 it was estimated that biodynamic agriculture occupied about 1,250 hectares, mainly in viticulture, and currently, there are eight wineries in the country where wine is produced using this production method that takes into account the observation of the stars.

An example of this trend is the Tagua Tagua Observatory, which, under the direction of physicist Ian Hutcheon, has combined astronomical observation and wine production. Through a tourist observatory in San Vicente de Tagua Tagua and the development of wines that connect with the objects and energy of the universe, this winery has united Chile’s long winemaking and astronomical tradition.

Ian Hutcheon explains that, in the case of the Tagua Tagua Observatory, the connection of wines with the stars begins from the fermentation of the must, that is, after the grape harvest. “We created the first wine in the world aged with meteorites. Later, we made another wine, “Taste the Stars”, a wine exposed to electromagnetic waves from space converted into audio so that the wines can vibrate with a distant object in outer space over a month,” detailed the director of this project.

Light pollution and its threat to agriculture

Currently, the ancestral relationship between dark skies and agricultural production is being seriously threatened by light pollution. The excess of artificial lighting not only affects the observation of the stars for crop planning, but also, scientific evidence shows that it is negatively impacting agricultural production in general.   

Pollinating insects, such as butterflies, flies, bees, moths, among others, play a crucial role in agriculture. According to the Food and Agriculture Organization of the United Nations (FAO), more than 75% of the world’s food crops depend to some extent on pollination. However, according to various studies, light pollution is interfering with the activity of nocturnal pollinators, being one of the factors of the so-called “insect apocalypse”

In 2017, a team of scientists in Switzerland sought to understand how artificial light could affect the interaction between pollinators and plants. Through the installation of LED lamps in orchards, they discovered that illuminated areas received 62% fewer insect visits and 29% fewer pollinators compared to other areas. Additionally, according to the study, fruit production of the plants was reduced by 13%, suggesting that diurnal pollinators cannot compensate for the decrease in nocturnal ones.

Artificial light also interferes with the nocturnal behavior of insects. A study published in Biological Conservation analyzed more than 200 previous studies, and concluded that artificial light disorients the flight of insects and with it their ability to mate, orient themselves, and avoid predators.

Indeed, light pollution, along with changes in land use, pesticide use, climate change, and habitat loss, is reducing nocturnal insect populations globally. According to a study published in the journal Annals of Applied Biology in 2018, light pollution is particularly affecting insects that provide crucial ecological services for agriculture, such as pest control and pollination.

According to Fundación Cielos de Chile, this demonstrates that actions to prevent light pollution should not only focus on astronomical regions but throughout the national territory. “The excess of artificial light not only affects the observation of the stars, but also, scientific evidence shows that it impacts people’s health and biodiversity. The good news is that the New Lighting Standard –which comes into effect in October 2024–, extends the protection of night skies to the entire country, so today the challenge is to disseminate this standard and for more actors to take measures against light pollution,” stated Daniela González, executive director of Fundación Cielos de Chile.

According to figures from the European Commission, animal pollination contributes 5 billion euros a year to the agricultural production of the European Union. Meanwhile, a study published by Ecological Economics estimated the contribution of pollinators to the economy in Latin America at US $22.5 billion. “This demonstrates that preventing light pollution has a positive impact on our economies and is a relevant component for the sustainable development of our communities, not only in the north of the country but throughout our territory,” concluded the executive director of Fundación Cielos de Chile.

By the end of 2024, the team behind the project hopes to be able to publish the first results of the monitoring network on the impact of excess artificial light in the area.

In July 2023, the University of La Serena presented the IluminAconciencia project, which is funded by the Regional Competitiveness Innovation Fund (FIC-R) of the Regional Government, and aims to measure the brightness of the night sky in the region and train local tour guides on the issue of light pollution.

Marcelo Jaque, astronomer, researcher at the University of La Serena and project director, says that one of his main motivations is to provide data for decision-making in the area. “With the cameras we used before, we had instant images, but with this network, we have constant and continuous monitoring, which allows us to take measures over time. Our intention has always been to provide all the information to decision-makers,” he explained.

The publication of the most significant results of this network is expected by the end of this year, after each of the meters can be installed for a minimum of six months. “We already have results, but to publish them, we want to have all the information. For this, we need many nights without a moon or clear skies; otherwise, the brightness of the night sky can be amplified or reduced due to external factors that are not just artificial light,” pointed out the project director. 

The network of 20 technological nodes in the Coquimbo Region

The purpose of IluminAconciencia is divided into two main functions. One is the monitoring network, composed of fifteen technological nodes that measure the brightness of the night sky in various places in the region.

These measurement points are located in various tourist observatories in the region, and some have been placed in local schools to raise awareness among new generations about the impact of light pollution. The oldest nodes have been installed for about a year, and within the coming months, they hope to complete the twenty contemplated by the project.

“We are installing nodes in schools mainly to explain how this technology works. But also, to generate meaningful learning by allowing children to have an instrument at hand that generates information from their schools,” commented Marcelo Jaque during his presentation at the Light Pollution Measurement Seminar in Chile 2024, organized by the Pontifical Catholic University of Valparaíso.

Additionally, the project includes training for astro-tourism guides in the area, who serve as ambassadors for the protection of the night skies.

Light pollution: a problem not only for observatories

 The IluminAconciencia team has also sought to inform and raise awareness among the inhabitants of the Coquimbo Region about the issue of light pollution, not only as a problem for astronomical observatories but as a phenomenon that affects people’s health and the environment.

In order to bring the topic closer to the public, the project has broadcast radio messages on community radios in the region, held astrophotography contests, and implemented a social media outreach strategy, among other initiatives.