Astrotourism in Coahuila, why the sky here is still dark

More than a third of humanity can no longer see the Milky Way from where they live, and the figure rises to almost 80% in North America (Falchi et al., reproduced by NASA, June 30, 2016 [1]). In the semi-desert around Paredón, Coahuila, the sky stays dark mainly because of low population density and distance from cities: the locality had 1,003 inhabitants in INEGI's 2020 Census [10] and sits about 80 km by road from Saltillo [11], far from the skyglow that DarkSky International defines as the brightness of the night sky over inhabited areas [8]. In the least populated parts of the Coahuila semi-desert, the night sky keeps artificial-brightness levels far below those of cities, according to the same atlas [1], and in April 2022 the largest dark-sky reserve certified to date was designated, with territory inside the state (DarkSky International, 2022 [2]). That contrast is the basis for the astrotourism the Museo del Desierto in Saltillo, under a European Union initiative, began promoting in 2024 [7].

Key facts

• More than a third of humanity cannot see the Milky Way with the naked eye; in North America the figure reaches almost 80% (NASA/APOD on Falchi et al., 2016 [1]).
• Coahuila is home to part of the Greater Big Bend International Dark Sky Reserve, certified on April 7, 2022, the largest certified to date at 38,850 km² (DarkSky International [2] [3]).
• On the Mexican side it includes Maderas del Carmen, Ocampo and Cañón de Santa Elena; DarkSky International places these Mexican protected lands of the reserve in Coahuila, in northern Mexico (DarkSky International, 2022 [2] [3]).
• In 2026 the Perseids peaked on August 13, with a new moon, and the Geminids will peak on December 14 (UNAM Global, 2026 [6]).
• In 2024 the Museo del Desierto in Saltillo began promoting astrotourism in municipalities such as Cuatrociénegas (Milenio, 2024 [7]).

How bad is light pollution worldwide?

The world atlas of artificial night sky brightness, built from satellite data and thousands of field measurements, concludes that "the historically common appearance of our galaxy at night is now lost for more than one-third of humanity. That includes 60% of Europeans and almost 80% of North Americans" (APOD/NASA on the Falchi et al. atlas, June 30, 2016 [1]). It advances with every new fixture, but it has one way out: "unlike many other forms of pollution, [light pollution] is reversible," notes DarkSky International [8]. Fixing the light source reverses the effect, with no remediation work needed.

Why does the Coahuila semi-desert stay dark?

A dark sky depends above all on distance from cities and low population density, two conditions the Coahuila semi-desert meets; across the Paredón aquifer zone, arid and semi-warm, with average annual rainfall of 256.8 mm and potential evaporation of 1,856 mm (CONAGUA, 2024 [9]), that aridity is constant. The same aridity also shapes the desert's biodiversity and water management in the area.

The same desert holds the Greater Big Bend International Dark Sky Reserve: 38,850 km² spanning Texas and northern Mexico, certified in 2022 after decades of lighting ordinances and work by local organizations, with Maderas del Carmen, Ocampo and Cañón de Santa Elena on the Mexican side [2] [3]. That is not the Paredón area, which sits far away, but it confirms the Coahuila desert offers uncommon conditions.

What can you see with the naked eye, and when, in 2026?

If you head out with no telescope or binoculars, on a moonless night, in the least populated parts of the semi-desert the sky keeps artificial-brightness levels far below those of cities (Falchi et al. [1]), usually enough to pick out much of the Milky Way. Andromeda is also visible, the nearest major galaxy to our own: magnitude 3.1, light that left 2.5 million years ago, visible to the naked eye even with moderate light pollution (NASA Science [5]).

According to UNAM Global, the Perseids peaked on August 13, coinciding with a new moon, "which will allow observing a large number of meteors per hour across the country" (translation); the Geminids, "one of the most constant and intense showers of the year" (translation), will peak on December 14 [6]. The rest of the calendar is in the table below.

What astrotourism initiatives exist in Coahuila?

Astrotourism — "moving visitors to places where the night sky is free of pollution" (translation) — already has a local driver. In 2024, the Museo del Desierto in Saltillo began visiting municipalities such as Cuatrociénegas to present an astronomical tourism plan to local authorities, according to the museum's director, Arturo González González, quoted by Milenio [7]. It aims to attract people from cities like Monterrey, toward skies that no longer exist where they live [7]. To plan a night visit: what to do in Paredón, the project and a tour.

How do you protect a dark sky when building?

DarkSky International sums up responsible outdoor lighting in five principles: useful — with a clear purpose —, targeted downward with no spill into the sky, low-level, controlled with timers or sensors, and warm-toned rather than cool white [4]. These are design decisions made before installing a fixture: fixing them afterward costs more.

What astronomical events mark 2026 in the Coahuila sky?