Astrophotography in Argentina: Dark Sky Sites from San Juan to Patagonia

Argentina has the same Andes as Chile on its western edge and a great deal of empty country east of them. Most of the population lives around Buenos Aires, Córdoba, Rosario and Mendoza, and once you are a few hours from those cities the sky gets dark quickly.

Argentina has no DarkSky International certified place yet. What it has instead is a national park with two professional observatories inside it, several public observatories, and a national tourism board that now lists astronomy as a reason to visit. These are the places worth the drive.

El Leoncito National Park, San Juan

The best-known dark sky in the country. The national parks administration says the park gets more than 300 clear nights a year and calls it one of the best places in the southern hemisphere for observing. It protects more than 89,000 hectares in Calingasta, and the park office is in Barreal.

Two observatories work inside it. The Complejo Astronómico El Leoncito (CASLEO) stands at 2,552 metres and offers day and night visits, with dinner and lodging as options. The Estación de Altura Carlos U. Cesco looks out over Cerro Mercedario and the Pampa del Leoncito.

Suits: anyone serious about a deep-sky trip. A booked night at CASLEO plus a few nights of your own in Barreal is a good plan.

San Juan city and its observatories

If you are passing through the provincial capital, the Observatorio Félix Aguilar in Chimbas runs guided visits by reservation, and the Observatorio Domingo F. Sarmiento in San Martín holds weekend night sessions, also booked ahead. Neither is a dark site, but both are a useful first night to check your gear before heading west to the mountains.

Suits: the first or last night of a San Juan trip.

Ampimpa, Tucumán

In the Valles Calchaquíes at 2,500 metres, the Observatorio Astronómico de Ampimpa runs night observing sessions for all ages. Booking ahead is the safe plan, as with every observatory in this guide.

Suits: combining with a trip through the northwest, toward Salta and the Puna.

Iberá, Corrientes

The Iberá Starlight project offers guided night experiences across more than 750,000 hectares of protected wetland, with Colonia Carlos Pellegrini as the usual base. Wetland air is more humid than the Andes, so expect dew and bring a heater for your lens.

Suits: nightscapes with water in the foreground, and anyone who wants wildlife by day.

Patagonia: Los Alerces and the far south

Argentina’s tourism board describes Los Alerces National Park in Chubut as having one of the purest skies in the country, with stargazing run by local providers in authorised areas. Further south, El Calafate and Ushuaia put you at high southern latitudes, where the south celestial pole stands well up in the sky.

Suits: wide-field and star-trail work around the pole, and long winter nights.

Córdoba and Mendoza

Near Capilla del Monte in Córdoba, the Villa Cielo municipal reserve was the first lodging in Argentina with a sky certified by the Starlight Foundation. In southern Mendoza, Malargüe has a planetarium and the Pierre Auger cosmic-ray observatory.

Suits: a weekend from Córdoba city, or a stop on a road trip through Mendoza.

Processing what you bring home

Akastroid takes the folder you shot in San Juan or Patagonia and stacks, calibrates and finishes it on your own computer, without uploading anything. The free download processes three sessions and allows one export, so you can put one full night through before deciding anything. If you buy a licence later, PayPal works for paying from Argentina, with a PayPal account or a debit or credit card.

For what changes between a city sky and a dark one, see removing light-pollution gradients, and for a first Milky Way session with only a camera and a tripod, the Milky Way without a star tracker.