From the April 2018 issue

The Astronomy in Chile Educator Ambassadors Program: Sharing the skies above Chile

ACEAP is a unique collaboration forged by astronomical observatories and educators under some of the darkest skies in the world.
By | Published: January 29, 2025

Chile is home to SOME of the world’s best skies — and some of the world’s most advanced instruments to observe them. From the radio telescope array charting complex chemistry in Titan’s atmosphere to the telescopes that pinpointed the neutron star merger last year, Chilean observatories play a starring role in today’s groundbreaking discoveries.

Many of these world-class facilities are partially or fully funded by the United States. Public enthusiasm and appreciation underpin successful projects such as these, ensuring the support necessary for future growth and continuing scientific discovery. Although astronomy excites many Americans, most are unaware of the substantial investments made by the United States and Chile — together — in pursuit of understanding our universe.

The Astronomy in Chile Educator Ambassadors Program (ACEAP) aims to change that. Now in its fourth year, ACEAP brings American astronomy educators to Chile to demonstrate firsthand how astronomical facilities function, how they make their data and discoveries accessible to the public, and how astronomy and science benefit communities on a local and global scale. The program represents the collaborative efforts of Associated Universities Inc. (AUI), the Association of Universities for Research in Astronomy, the National Radio Astronomy Observatory (NRAO), the National Optical Astronomy Observatory, and Gemini Observatory. ACEAP is supported by the U.S. National Science Foundation (NSF).

Participants go behind the scenes at some of the world’s premier astronomical observatories. This amazing opportunity comes with the responsibility to return home and spread what they have learned throughout their communities.

Informed messengers

ACEAP gathers individuals from across the U.S. and transforms them into a group of informed communicators and advocates for astronomy, with a focus on the scientific partnership between the United States and Chile. Each year, the program selects nine ambassadors, and the ACEAP team — and family — grows. Past ambassadors remain active in the program, creating a foundation of support and sharing resources with each other and future ambassadors.

Although the destination is always the same, ACEAP differs each year because each group of ambassadors is unique. “Every group that comes to Chile as part of this program takes away something different. But, to a person, there is the same infectious enthusiasm to share their experiences with as many people as possible,” says Charles Blue, NRAO’s public information officer and co-principal investigator of the program.

I traveled to Chile in 2017 as ACEAP’s first media liaison. The other ambassadors were planetarium directors, astrophotographers, teachers, and research assistants. One was a Chilean educator leading K-12 astronomy education in her school. Many members of the diverse group have their hands in multiple projects: spearheading efforts to preserve dark skies, providing the public with pop-up telescope viewing, and leading local astronomy clubs and events.

First steps

Map of Chile
This map shows the locations of the observatories on our packed itinerary. Credit: Astronomy: Roen Kelly

Our nine-day program officially began June 18, 2017, in Chile’s capital, Santiago. Each day was packed, typically beginning at 7 or 8 a.m. and wrapping up in time for dinner around 8 p.m. (Eating late is common in Chile.) We took three flights and several long car trips to reach not only the observatories, but also nearby towns and unique landscapes unlike any I’d seen before.

We visited Cerro Tololo Inter-American Observatory (CTIO), the Gemini South Observatory, and the Atacama Large Millimeter/submillimeter Array (ALMA). We also stopped at Observatorio Astronómico Andino (OAA) near Santiago and Observatorio Cerro Mayu near La Serena — two observatories that are part of a growing astronomical tourism industry catering to people who want to travel to and within Chile to experience the spectacular skies.

Just outside OAA’s rustic but high-tech lodge, many of us got our first look at the Southern Hemisphere night sky. Globular cluster Omega Centauri and the Carina Nebula were stunning through telescopes, while Alpha and Beta Centauri, along with nearby Crux the Southern Cross, stood out brightly to the naked eye amid the rich southern Milky Way. Some familiar constellations remained — Scorpius, for example — but appeared oddly misshapen, backward and upside down from their Northern Hemisphere apparitions.

“What I’ll always remember is the feeling of seeing the Southern Hemisphere stars and not knowing what the heck I was looking at,” says ambassador Amy Jackson, an educator from Austin, Texas, and founder and director of Starry Sky Austin. “For someone who knows the constellations and sky so well, to look up and feel lost is the most disorienting feeling. It really helped me to understand how the students and public I teach in my classes and programs must feel.”

The Observatorio Cerro Mayu marries Chilean culture with the beautiful dark sky. Cerro Mayu’s large outdoor sculptures carry both astronomical and cultural significance, highlighting Chileans’ deep relationship with their sky. Although we were blown away at OAA the night before, the weather was better and the sky even darker at Cerro Mayu, prompting an evening of excited astroimaging.

World-class observatories

We spent two nights at CTIO, touring the observatory by day and forgoing sleep to stargaze at night. ACEAP encourages ambassadors to document their trip every step of the way; we filled much of our scheduled “downtime” with image processing, blogging, or posting on social media. Some spoke with students back home via webcam. The experienced astroimagers generously shared tips — and even equipment — with those of us new to night-sky photography.

We toured the 4m Víctor M. Blanco Telescope and the Yale 1m telescope, part of the multinational Small and Moderate Aperture Research Telescope System. 

Our visit also took us to nearby Cerro Pachón, where the 4.1m Southern Astrophysical Research Telescope and the 8.1m Gemini South Telescope reside along with the construction site for the Large Synoptic Survey Telescope. We climbed the steps alongside the towering Gemini Telescope to see its silvered primary mirror up close, and craned our heads back as telescope operators opened the dome and moved the telescope, the entire dizzying process smooth and nearly silent.

In the Atacama Desert, we visited local schools in San Pedro and Toconao with two 2016 ambassadors who’d returned to Chile for outreach. We observed science classes and gave live demonstrations on topics such as infrared light and safe solar viewing. (Chile lies in the path of totality for the July 2, 2019, solar eclipse.) We handed out eclipse glasses, maps of the Moon, and photosensitive beads to primary and high school students.

Our visit to ALMA began at the Operations Support Facility (OSF) at 9,500 feet (2,900 m) in elevation. It contains staff offices, labs, and the telescope control room where astronomers observe. In one lab, we saw several of ALMA’s front-end receivers, which digitize and amplify signals received by the dishes.

The general public can visit the OSF, but few people — astronomers included — visit ALMA’s Array Operations Site (AOS) 17 miles (28 kilometers) away, where the antennas sit on the Chajnantor Plateau 16,500 feet (5,000 m) above sea level. We were invited to visit the AOS, provided we passed a mandatory physical and observed a two-hour time limit. Traveling to high altitude raises both heart rate and blood pressure, so our vitals were checked that morning. We were all cleared for the trip.

The day was clear and crisp with a deep blue sky, and the often-windy plateau was relatively calm with scattered piles of crystalline snow and spiky fields of ice. Each of us carried an oxygen tank; at that altitude, the atmosphere contains only about 55 percent of the oxygen it does at sea level. First, we toured the AOS Technical Building, the world’s second-highest building, which houses the correlator supercomputer. Capable of performing 17 trillion calculations per second, it combines signals from the observatory’s 66 radio dishes, allowing them to work as a single telescope.

Next, we drove out to walk among the 100-ton antennas, some rotating — swiftly and silently like their optical counterparts — in testing mode. We marveled at the engineering, ingenuity, and perseverance required to build and operate a telescope array in such an extreme environment.

Astronomical community

Young student with bottle rocket
At the Toconao school near ALMA, the ambassadors engaged in a morning of exploration with young students eager to learn more about astronomy, physics, and biology. Credit: Alison Klesman (ACEAP/NSF)

ACEAP ambassadors don’t spend all their time inside domes or atop high-altitude plateaus. We also attended science and engineering presentations on how the observatories work and the process astronomers follow to observe. Education and public outreach officers spoke about STEM education and outreach throughout Chile. We learned how to use ALMA and Gemini data in classrooms, planetariums, and lecture halls back home. Panels featuring CTIO and ALMA administrators, engineers, telescope operators, and more drove home the point that astronomers are only one part of a much larger community standing behind these successful observatories.

That community includes U.S. and Chilean citizens. Each observatory dedicates significant resources to promoting science and astronomy. “In more than 40 years of doing outreach at the Cerro Tololo Inter-American Observatory, we have reached more than 100,000 people just here in the visitors center,” says Juan Seguel, coordinator of Education and Public Outreach (EPO) at CTIO.

Ambassador Rich Lohman explored the reasons why the ACEAP group comes to Chile each year. “During our ACEAP trip, I asked a couple of our speakers . . . the value of putting our money into astronomy,” he says. “I heard basically this: Humankind has always been searching the big questions. Where did we come from? Where are we going? Where are we in a larger perspective? We’re always looking for greater understanding of the biggest possible picture. So we as a society of humans should financially support what we’re deeply called to do and try to answer those very profound questions.”

ACEAP ambassadors also experience the culture and natural beauty of Chile. In Santiago, several of us visited the La Chascona house built by Nobel prize-winning poet Pablo Neruda. We took in panoramic views of the city and the snow-covered Andes from the top of San Cristóbal Hill. In the Atacama Desert, we visited the Reserva Nacional de Flamencos, a sprawling salt flat ringed by distant volcanoes. We drove through the stunning Valle de la Luna (Valley of the Moon), named for its striking similarities to the surface of Earth’s satellite. Much of the ground consisted of deep-red sand dunes or sat beneath a blanket of white — salt, not snow. Ambassadors shopped at San Pedro’s craft markets before our flight back to Santiago and our last day together.

A continuing journey

The ability to share data and knowledge instantaneously across continents makes it easier than ever for the public to access cutting-edge science. A love of science often starts early, putting educators in the unique and vital position to nurture and support it.

The trip to Chile is only part of ACEAP. Ambassadors must also complete seven outreach projects associated with their experience that highlights astronomy in Chile. That final day in Santiago, we talked about outreach goals, some spanning continents to include returning to Chile for future outreach.

Among the projects are public lectures, classroom activities, blogs and print articles, and planetarium shows. Angela Osterman Meyer is incorporating data from Chilean observatories into high school science classes in Culver, Indiana. Alice Few of Tacoma, Washington, spoke about ACEAP and STEM at the 2017 Girl Scouts of the U.S.A. national convention in Columbus, Ohio. “Additionally,” she says, “it looks like I will be leading a group of Girl Scouts back down to Chile for STEM exploration and the 2019 eclipse! I’ll be working with María Rebeca Lopez [the 2017 Chilean ambassador] on that project so my girls, her students, and the Chilean Girl Guides can have a joint project.”

Jackson turned her awe at the sheer size of the telescopes into a scale model of the 8.1m Gemini mirror using mylar emergency blankets. “Since most of the people I come in contact with will never get to go to Chile, I hope getting to experience the enormous size of the Gemini mirror will spark some interest. It also serves to discuss the light-gathering power of telescopes and spark interest and questions about research being done in Chile,” she says.

But ACEAP ambassadors are not, by nature, satisfied to stop once their initial outreach projects are complete. They want to continue inspiring interest in astronomy, science, and technology — now not alone, but as part of a larger, coordinated effort. “We don’t take the trip; the trip takes us,” says Ed Ting, an amateur astronomer and astrophotographer from Manchester, New Hampshire. “I went to Chile hoping to learn about astronomy, telescopes, and to try out some astrophotography techniques. While those things did happen, I also immersed myself in the Chilean culture and made friendships that will last a lifetime.”

Tim Spuck, ACEAP principal investigator and STEM education development officer for AUI at NRAO, has now guided three groups through Chile. “For each ambassador, in many ways, ACEAP is its own unique journey,” he says. “I’ve discovered over the years that while there is much in common with the ambassadors, each has a special reason for taking part. This collage of motivations and passion for astronomy results in a unique work of art for each ACEAP cohort. It has been a joy and a privilege to travel this road with each of them.”

The 2018 ambassadors are now preparing for their trip. The ACEAP family grows, and with it the resources for cultivating new opportunities for partnerships across the United States and Chile. Thanks to the support of the NSF, its superb facilities and their staff, and programs like ACEAP, more of America’s astronomy educators and enthusiasts are becoming part of a network dedicated to bringing astronomy down to Earth and kindling in people around the world a love of the sky we all share.

ACEAP, like astronomy in Chile, is about people.

Shooting star
While taking a self-portrait with the Milky Way and Magellanic Clouds, I serendipitously caught a shooting star. Credit: Alison Klesman (ACEAP/NSF)