Stargaze in the Heart of Atacama Desert
Considered the longest country in the world at 2,700 miles in length and only 109 miles wide, Chile stretches down South America’s western ridge along the Pacific Ocean coastline. It’s a country known for world class wine, herbaceous pisco, steamy empanadas and the national dance of cueca but more than anything, Chile’s most remarkable feature is its unique geography; the uniqueness of its territory and biodiversity. Its capital, Santiago, lies in a valley surrounded by the Andes and Chilean Coast Range mountains, while San Pedro de Atacama is so dry that it emulates life on Mars. Located in the extreme south of Chilean Patagonia, Torres del Paine is known for its spectacular views, formidable mountain ranges and unpredictable weather.
The Atacama Desert is a desert plateau in northern Chile covering a 1,000 mile strip of land on the Pacific coast, west of the Andes Mountains. The driest non-polar desert in the world and the second driest overall, most of the desert is made up of stony terrain, salt lakes, sand and felsic lava that flows toward the Andes. Still, Atacama is filled with wonder and discovery. Though extreme, the landscape is stunning, full of geysers, lakes and endless valleys, not to mention, the nighttime skies are packed full of stars.
Visiting Chile for two weeks was surely an undertaking. With eight flights, countless bus and taxi rides and even a ferry, the three regions we explored were central, northern and southern. First up was the capital city of Santiago, to enjoy Chilean wine, world Class cuisine and an undeniable art scene. Then, we moved north to San Pedro de Atacama, the driest place on Earth, where we joined incredible tours, including Chaxa Lagoon, Piedras Rojas and Altiplanic Lagoons, the Andes Mountains to experience El Tatio Geysers, northern Atacama to moonwalk at Valle de la Luna and Atacama desert to stargaze into the night sky. From there, we flew to the tip of Chile's southernmost Patagonia region and gateway to Antarctica, Punta Arenas, and then to Torres del Paine, Chile’s Patagonia, with an exciting opportunity to witness Patagonia’s waterfalls, icebergs and glaciers. Last but not least, our journey lead us to Castro on Chiloé Island, land of myth and sea.
Favorite places to visit in Chile
Contents
Begin Your Celestial Discovery
Wonder at Atacama’s Night Sky
Peer Into Giant Telescopes
Pose with the Stars & Sip Hot Chocolate
Begin Your Celestial Discovery
Moving between two tour agencies in San Pedro de Atacama, Turismo Gato Andino and Horizons, we booked several tours during our stay, one of which was an evening stargazing tour for about $40 USD. During this after-hours tour, a small group is guided into the Atacama Desert to enjoy a celestial discovery like no other. Guests are given a general introduction to the sky and its observation with the naked eye, followed by observations using several large telescopes. The tour will end with a hot drink and a photo in front of the starry sky.
Tip:
Wear warm clothes & bring bottled water.
With a pick up time of 9 p.m., we joined the tour and made our way outside of town to our final destination. Our small group unloaded and followed Margarita, our guide, into the wilderness. Within a few moments we arrived at the observatory, a modest plot of land where she lived and worked. We were led to a clearing with seating curved in a semi-circle and two large telescopes (one much larger than the other). As we took our seats, Margarita began to explain, “Why stargaze in Chile?”
Chile is a top destination for stargazing, some say the world’s best, because of its dark skies, high altitude, dry atmosphere and lack of light pollution. Chile has more than 2,000 miles of mountain range running through it, creating large swathes of wilderness, which is essential for successful stargazing. Within Chile, the best locations to stargaze are the Atacama Desert, Elqui Valley and Pangue Observatory. Located in northern Chile, Atacama Desert is one of the driest places on Earth. Its high altitude and low humidity make for clear skies and crisp, sharp views. The desert also has few clouds, with close to 300 clear nights each year. Additionally, some of the world's largest and most advanced observatories are located in the Atacama Desert including Paranal Observatory, Las Campanas Observatory, Atacama Cosmology Telescope (ACT) and Observatorio Etno-Astronomico.
Paranal Observatory, operated by the European Southern Observatory (ESO), is located on Cerro Paranal (a mountain with an elevation of 8,645 feet) and is the largest optical-infrared observatory in the Southern Hemisphere. Established in 1969 by the Carnegie Institution for Science, Las Campanas Observatory is known for its clear and stable dark skies. Atacama Cosmology Telescope is a 20-foot observatory that operated between 2007 and 2022, studying the cosmic microwave background and contributed to cosmology. Observatorio Etno-Astronomico offers a special chance to observe stars, planets, asteroids and galaxies. Even more, Gemini Observatory features a 27-foot telescope, while ALMA Observatory features a radio-telescope array. Many of these observatories are open to the public, so check out their offerings. Piedras Rojas is another unique location to view the night sky. A two hour drive south of San Pedro de Atacama, the area sits at 13,000 feet, with a shallow salt flat surrounded by red colored rocks and mountain peaks protruding into the starry sky.
Margarita also explained that because we’re in the Southern Hemisphere, what we’d see would be very different from that in the north. In fact, this sky is filled with many more constellations and its stars are much brighter than those in the Northern Hemisphere. There, Earth points toward the outer edges of the Milky Way, while in the south, Earth faces directly into the Milky Way’s galactic center, with views of billions of stars.
In the Atacama Desert, it’s possible to see some but not all of the constellations you might be familiar with at home. And depending on the time of year, they may look exactly the same but being on the other side of the Earth you can also view some constellations and stars that aren’t visible elsewhere. Some of the most breathtaking include the Southern Cross, Vela, the Jewel Box Cluster, Omega Centauri and Eta Carinae Nebula.
Wonder at Atacama's Night Sky
It was about this time when Margarita pulled out a powerful laser pointer, that was able to shoot up into the sky and reference which stars she was describing. Knowledgeable and steady, she began to detail several of the constellations visible to the naked eye, constellations like the Southern Cross, Vela, the Jewel Box Cluster within the Southern Cross, Omega Centauri, Eta Carinae Nebula, Scorpius and the Milky Way. Continuing, she said, it’s also possible to see bright stars like Velorum from the Vela constellation and observe the colorful stars within the Jewel Box Cluster.
The Southern Cross is a famous constellation on this side of the world, appearing on both New Zealand’s and Australia’s flags, though, many from the north have never witnessed it. The Jewel Box Cluster is a group of stars within the Southern Cross. It’s packed full of brightly colored stars including red and blue supergiants (stars that are the most massive and luminous) which are a real treat to witness. Vela is a constellation that means “ship’s sails” in Latin and Vela is home to the star Velorum, a very bright supergiant. Omega Centauri is a cluster that sits next to the Jewel Box and is the second brightest seen anywhere in the sky. It’s the largest cluster of stars orbiting the center of the Milky Way and as you can imagine, it’s very special through a telescope. Eta Carinae Nebula is a bright nebula (cloud of dust and gas, usually tens to hundreds of light years across) home to one of the most exciting stars in the Milky Way because it’s very unstable. Experts think it might be the next star to die in a stellar supernova explosion.
The Milky Way is the galaxy that contains our solar system and is exceptionally visible due to the dark skies of Atacama. It's a spiral galaxy made up of stars, gas clouds and dust; its name coming from the band of light that appears across the night sky as seen from Earth. The “Seven Sisters” in the Milky Way refers to the Pleiades star cluster, a group of stars visible to the naked eye. They appear as a cluster of seven bright stars in Greek mythology, where they are depicted as the daughters of Atlas and Pleione. The Pleiades are located within the constellation Taurus and are named Alcyone, Asterope, Celaeno, Electra, Maia, Merope and Taygete. While you can see the main stars with the naked eye, binoculars or a telescope will reveal many more stars within the cluster.
Another celestial form Margarita spoke about was Orion’s Belt. Orion’s Belt is an asterism in the constellation Orion; a distinguished pattern or group of stars, typically having a popular name but smaller than a constellation. Orion’s Belt is made up of three stars: Alnitak, Alnilam and Mintaka, which are arranged in a nearly straight line (similar to a belt). It’s also known as the Three Kings or Three Sisters and is easiest to view in the early night sky during the Northern Winter or Southern Summer.
The brightest star in the sky is Sirius, also known as the Dog Star, while others of note include Alpha and Beta Centauri, two bright stars in the constellation Centaurus, Antares, a bright red-orange star, and Canopus, located in the constellation, Carina. Both the Magellanic Clouds, two galaxies that orbit the Milky Way galaxy, and hydrogen nebulae, a cloud of gas in space primarily composed of hydrogen that often appears red in color, are also visible in Atacama’s night sky.
And finally, Margarita clarified exactly why the night sky is richer in Chile’s Southern Hemisphere. The primary difference between the sky visible in the Atacama Desert (Southern Hemisphere) compared to the Northern Hemisphere is that the Southern Hemisphere offers a much clearer view of the Milky Way's galactic center, revealing a denser concentration of stars and brighter constellations, due to Earth's orientation towards the galactic plane (plane that the majority of a disk-shaped galaxy lies) in that hemisphere; basically, the Southern Hemisphere sky appears much richer and more detailed with prominent constellations like the Southern Cross that are not visible in the North.
All in all, the Southern Hemisphere is best for viewing the Milky Way in all its glory, leading to much more striking views of the galactic band when compared to the Northern Hemisphere. It’s also a location where unique constellations like the Southern Cross, Centaurus and Carina are visible, along with some of the brightest stars in the night sky, like Sirius, Canopus and Alpha Centauri.
Peer Into Giant Telescopes
From there, Margarita positioned the two telescopes at various celestial objects and encouraged us to step up and take a peak (without touching the telescope whatsoever). She let us view baby stars, nebula, the Moon and various other “old” stars, one by one.
A baby star, also known as a protostar, is a young star that is still gathering mass from a molecular cloud. Protostars are the earliest phase of a star's life cycle. Baby stars are formed in dense clouds of gas and dust called nebulae, where the cloud collapses in on itself due to gravity, forming an opaque and pressure-supported core. The protostar grows larger, hotter and brighter as it gathers more material and eventually becomes hot enough for hydrogen fusion, which releases energy and creates a new star. The leftover material in the disk around the protostar forms planets. Interestingly, protostars release gas and dust in “sneezes” and some nebula like the Orion Nebula are star-making factories that contain upward of 1,000 young stars.
Of course, the Moon is Earth's only natural satellite and a rocky body that orbits Earth about 238,600 miles away. With a surface gravity about one-sixth of Earth's, the Moon is made of iron, magnesium, aluminum, silicon, titanium, gold, silver and mercury. The Moon's appearance changes throughout the month as it orbits the Earth and reflects sunlight. These changes are called phases and there are eight phases in total.
Views of the Moon through the telescope were absolutely incredible; I’d never seen anything like it. Its surface was crystal clear. Margarita grabbed our phones and placed them atop her telescope and snapped a few photos of what we’d witnessed.
Old stars are those that are billions of years old, or close to the age of the universe itself, which is about 13.8 billion years old. To determine the age of a star, scientists take into account its spin rate (as stars slow down as they age) whether or not they have protoplanetary disks (those with disks are usually young) and its heavy element content (stars that formed before heavy elements were abundant in the universe have low levels of heavy elements). Other ways to distinguish stars are their color and size; reddish and orange stars are older and cooler, while blueish white stars are hotter and younger - and larger, heavier stars tend to spin faster than smaller, lighter ones.
The rest of what we viewed through the telescopes was very interesting. Some formations were clear as could be, while some looked a little blurry, as if they were placed on jelly or had wispy tails. Honestly, I couldn’t get enough; what a memorable experience.
Pose with the Stars & Sip Hot Chocolate
Margarita then made our dreams come true when she orchestrated individual photos of us looking up into the night sky. She’d set up a small light to illuminate us and then placed her camera on a long exposure to grab the stars behind us. The images turned out really special.
To finish off the already unbelievable evening, Margarita guided us to a folding table spread with snacks and hot chocolate. We enjoyed our hot drinks while we watched a video about the night sky. Tired and cold, the evening came to a close. We retuned to our stay around midnight and crawled into bed.
The Atacama Desert is said to be one of the best places in the world for stargazing because of its extremely dry climate, high altitude, minimal light pollution and near absence of humidity, creating crystal clear skies with perfect visibility of stars and constellations.