A Nation Looking to the Stars
Long before modern telescopes gazed into the heavens, Mexico had already embraced the mysteries of the stars. Since the early 19th century, thinkers like Simón Tadeo Ortiz dreamed of founding a national observatory. Philosopher and patriot, Ortiz believed Chapultepec was the perfect place to realize this vision.
Others agreed. In 1859, geographer Francisco Díaz Covarrubias declared that no other location in the Valley of Mexico offered such potential to contribute to geography and science. The dream lingered in the air until General Porfirio Díaz took office.
Fascinated by technology and scientific advancement, Díaz revived the idea. His advisors argued that with good astronomical observations, Mexico could develop more accurate maps—saving lives and improving the nation’s infrastructure.
The idea of Chapultepec astronomical observatory gained new urgency and, once again, all eyes turned to the heights of the hill.
Creating the Chapultepec Astronomical Observatory
The top of Chapultepec Castle was chosen as the site for the first internationally recognized observatory in the country. Though an observatory had existed since 1840 in the Palace of Mining, and the Maya had developed star-watching techniques centuries earlier, this new project aimed higher.
In 1876, Ángel Anguiano—an engineer and self-taught astronomer—oversaw the observatory’s creation. Equipment was acquired, including a meridian telescope and a heliograph. A dome was installed on the castle’s watchtower. By May 5, 1878, the Chapultepec astronomical observatory was officially inaugurated.
That same night, astronomers used theodolites to calibrate observations and recorded Mercury’s transit across the sun—the observatory’s first major achievement.
A Temple of Scientific Curiosity
More than just a telescope on a hill, the Chapultepec astronomical observatory became a hub of innovation. In August 1878, a coal microphone—predecessor to modern sound technology—was installed. Connected to a telephone line running to the National Palace, it allowed observers to hear organ music and human voices transmitted from afar. For many, it was like hearing ghosts in the castle walls.
Chapultepec scientists also contributed to education. Alberto Cárdenas, head of the National Preparatory School, began building larger microphones, signaling the close relationship between research and pedagogy. The observatory had become a living classroom for scientific experimentation.
The Transit of Venus and a Global Mission
One of the observatory’s grandest goals was the 1882 transit of Venus. This rare astronomical event—where Venus passes directly between Earth and the sun—only occurs in pairs every century. It offered astronomers a unique chance to calculate the size of the solar system and the Earth’s distance from the sun.
Mexico had already joined the global scientific stage in 1874, sending a commission to Japan to participate in Venus observations. By 1882, Chapultepec was prepared. Instruments were shipped from Europe. Hopes were high.
But fate had other plans. December 6, 1882, was a cloudy day. Observers caught only a few minutes of the event before the skies closed in. Still, the effort showed the world that Mexico’s scientists were ready to contribute to international science—and that the Chapultepec astronomical observatory was more than symbolic. It was a statement.
A Legacy of Aspiration
Though it faced setbacks—weather, politics, and shifting priorities—the Chapultepec astronomical observatory proved Mexico’s capability for scientific excellence. It served as a model for future institutions and fostered a generation of astronomers and engineers.
Today, the story of the observatory is a monument to vision and perseverance. Its brief window of activity in the late 19th century did not diminish its symbolic importance. The hill where emperors walked and children fought became, if only briefly, a temple of the cosmos.
Conclusion
The Chapultepec astronomical observatory was born from a national yearning to understand the universe and elevate science as a public mission. Though clouds may have obscured the transit of Venus, they never fully dimmed the observatory’s light.
It remains one of Chapultepec Castle’s most inspiring chapters—a scientific dream, if not fully realized, then at least immortalized among the stars.