Learn about a series of major discoveries and investigations on astronomy originating in Chile, the country holding approximately 40% of humanity’s astronomical observation capacity.
With clear evening skies 90% of the year, the skies of northern Chile are an incomparable natural laboratory for studying the Cosmos. It is not surprising that the regions of Antofagasta, Atacama and Coquimbo concentrate a large part of the world’s astronomical facilities. The Paranal Observatory and its Very Large Telescope (VLT) operated by the European Southern Observatory (ESO), the most advanced array in the world, and the Atacama Large Millimeter/submillimeter Array (ALMA), the largest radio observatory on the planet, are both located in the region of Antofagasta. The Las Campanas Observatory, owned by the US-based Carnegie Institution for Science, is located in Atacama, and the La Silla Observatory (ESO) and the Cerro Tololo Inter-American Observatory are located in the region of Coquimbo.
This is why it is no surprise that constant discoveries are being made by observatories located in Chile, such as last week’s discovery by a group of Chilean scientists, who identified what might be a new planet, which would have a mass 5 times that of Jupiter and would be 443 light-years away from Earth.
To add to the already existing enormous astronomic capacity in the desert, the next few years will see the arrival of tools that will increase Chile’s ground optical astronomical capacity from 40% to 70% of all humanity: the Vera C. Rubin Observatory, the Giant Magellan Telescope and the Extremely Large Telescope, which will be the largest optical telescope in the world.
Today we take a journey across ten major discoveries and investigations that have been made from observatories installed in Chile.
The best astronomic “tape measure” for a decade: Cataloged as one of the most important projects in Chilean astronomy, the Calán/Tololo Project (1989-1996), a Chile-US joint effort, studied the distances in the Universe. This project, which involved the work of two Chilean national prize winners in exact sciences, José Maza and Mario Hamuy, generated what was considered for almost a decade to be the best “tape measure of the Universe.” Calán/Tololo was key to a subsequent project that was awarded the 2011 Nobel Prize in Physics, the discovery of the accelerating expansion of the Universe.
First image of an exoplanet or extrasolar planet: This image was taken with one of the VLT telescopes in the Paranal Observatory in April 2004. This is a giant planet, approximately five times larger than Jupiter.
First supernova visible to the naked eye in over 400 years: In 1987, the supernova 1987A was discovered from Las Campanas. It was the first supernova visible to the naked eye in over 400 years, in the Large Magellanic Cloud, and its study confirmed the theory that elements such as iron were created in this type of explosion.
First photograph of a Supermassive Black Hole: In 2019 ALMA-APEX joined observatories in other parts of the world in the Event Horizon Telescope project. By combining images from these telescopes, this project was able to obtain, for the first time, an image of the event horizon of the supermassive black hole at the center of the Messier 87 galaxy. This discovery involved the participation of Neil Nagar, astronomer at the Center for Excellence in Astrophysics and Associated Technologies (CATA).
One of the first findings of a lonely brown dwarf: In 1987, María Teresa Ruiz, astronomer from the Universidad de Chile and director of the CATA Center for Excellence in Astrophysics and Associated Technologies, discovered the lonely brown dwarf baptized as Kelu (which means red in the Mapudungun language). Brown dwarfs begin their lives as stars, or as balls of gas, but they lack sufficient mass to generate light.
The closest Super-Earth: In January 2020, “Proxima Centauri c” was discovered, an exoplanet located 4.2 light-years from Earth, with a mass 6 times the mass of Earth. Its composition is more similar to our planet, rather than a large mass of gas like Jupiter or Saturn. Instruments located in La Silla and Paranal were used to detect it.
The sister of the Milky Way: Using the ALMA radio telescope, in August 2020, a scientific team discovered the farthest galaxy known to date (called SPT0418-47) with characteristics similar to the Milky Way, located 12 billion light-years away.
Evidence on the origin of black holes: In February 2021, Andrés Escala, astronomer from the Universidad de Chile, discovered that supermassive black holes, i.e., those whose mass exceeds the mass of the Sun by the billions, originate from the collapse of a stellar cluster at the galactic nuclei of gravitational structures.
The shape of the center of the Milky Way: For many years, it was believed that the central part of the Milky Way was spherical in shape. However, in 2010, studies led by Manuela Zoccali, astronomer from the UC Astrophysics Institute, showed that it actually has an X formation.
The Family Tree of the Milky Way: Astronomer Paula Jofré (who works in the Astronomy Nucleus of Universidad Diego Portales) chose 22 stars from the Milky Way, including the Sun, to develop a cosmic family tree, which also involved the study of the 17 chemical elements that connect these.
