Cerros Pachón & Tololo
30°14′40.7″S 70°44′57.9″W
Coquimbo Region, Chile
▲ 2629m

Two ridge peaks hold a cluster of powerful astronomical observatories. Their task: to help us see more clearly into the outer reaches of the cosmos and into ourselves.

Near the southern edge of Chile’s Atacama Desert—the driest place on Earth—the Andes Mountains roll endlessly over the horizon in every direction.

Just above the cloudline in Elqui Province, far from city lights, the sister peaks of Cerros Pachón and Tololo rise together, each home to a cluster of intensely powerful observatories.

These are among the most mythic and powerful scientific instruments humans have ever made.

Here in the foreground, Cerro Tololo holds a maze of 40 telescopes, including the nearly 50-year-old Victor M. Blanco Telescope, the spiritual matriarch of the peaks.

To the south, within eyeshot of Tololo, is Cerro Pachón, the site of SOAR and Gemini South.

The newest observatory on Pachón and one of Earth’s most powerful is the Vera C. Rubin Observatory. Over 20 years in construction, it is nearing completion and will see "first light" in early 2025.

Night sky
Night sky
Night sky
Night sky
Night sky
Night sky

Once completed, Rubin will begin a ten-year survey of the southern sky, creating the deepest, widest, and most complete map of the universe ever made and redrawing our understanding of the cosmos and our place within it.

Construction drawing
Rubin dome

The complexity of Rubin’s vast and interlocked systems—mirrors, camera, mount, dome, data pipeline, more—live at the edge of material possibility. Yet this complexity belies the poetic, out-of-time simplicity of the observatory’s task: to help us see.

In another age, an “observatory” might simply have been the patch of Earth we stood on as we looked up to find a bright wayfinding star at dusk...

Now, an "observatory" has morphed into a multigenerational undertaking with intricate networks of global partners, all circulating around a complex machine that is often perched atop a difficult-to-access peak.

Rubin dome

Within the oberservatories of Tololo and Pachón exist countless smaller objects, relations, and protocols—each its own industry and revelation.

These smaller moments can cleave into millions of even smaller but meaningful moments: The wishful lines of a napkin drawing...The care taken to weld a joint...An elaborate cable run...A novel line of code... A conversation.

Rubin and the other observatories on Cerros Pachón and Tololo, in their scale and elaborate systems of cooperation, can slip beyond the measure of their prescribed functions, beyond the sum of just their parts, into another evocative realm capable of recalibrating our imaginations.

As objects, their jobs are to help us see, but also to retool our vision, reshaping the contours of what we might dream.

Undergirding these dreams is a living chain of human touches...

Billions and billions of unique touch points.

Hands making contact. Transforming.

On the mountain, and around the world, as you read this, hands making contact.

Rubin dome
Rubin dome
Rubin dome
Rubin dome
Rubin dome

For all its complexity and interlaced systems, at its core, Rubin’s job might be distilled to another sort of “touch”: to make the most careful, sustained contact with light’s smallest ingot—photons...

As we gaze into the night sky, the light we see arrives to Earth, finding your eye—that light's first touch in more than a million trillion miles.

Rubin, by conjuring more photons per night than any telescope before it, charts a much wider and deeper path into time and space...

Light from interstellar objects, traveling in some cases for billions of years over unimaginable distances, somehow, against all odds...

Finds its first contact with a paper-thin surface of silver laid upon a perfect circle of glass—the spiritual core of the observatory...

The observatory's desire among desires is to catch and transform this cosmic light.

The Telescope Assembly Mount, a massive structure tasked with holding and positioning Rubin’s camera and two mirrors, is anchored directly to the mountain bedrock.

The largest mirror, the M1M3, is 8.4 meters in diameter, 86 feet around, cast of tons of low-expansion glass, heated and spun in a kiln, then, for years, ground, honed and polished to tolerances that place it among the most perfect forms humans have ever made. The mirror has the qualities of a mystical jewel, yet one weighing 52,000 pounds.

The surface of the glass is clad with a meniscus of pure silver, just 64 grams, or the weight of a few coins jingling in your pocket.

As primordial photons enter the observatory, they begin a carefully designed choreography of precision bounces, each one widening Rubin's view of the sky...

until a rendezvous with the largest lens of the most powerful camera ever built.

Here, in a camera as big as an SUV, ancient light is skillfully channeled toward Rubin's 3.2 billion-pixel sensor, where that light is transformed into data.

The sensor gathers light for 30 seconds before the telescope pivots to take a new picture. This process repeats again...

...and again every half-minute. The sum of these exposures, collected over three or four nights, are stitched together to compose the most detailed portrait ever of the southern hemisphere.

This process will repeat every night for a decade, each image—over 2 million in total—becoming part of a cosmic film of the universe unfolding in real-time. The seemingly static face of the universe now animated, alive with movement, change, and transformation.

Data 1
Data 2
Data 3
Data 4

These millions of images and the secrets they encode will be the biggest scientific data set ever produced: a 500-petabyte library. If this data were transcribed into books stacked side-by-side, they would circle the Earth 2000 times.

But the production of data is only the first step toward deciphering meanings within this immense dataset.

To facilitate analysis, an entire planetary-scaled data infrastructure has been constructed. Within seconds of the shutter closing on Pachón, an image will travel off the mountain in two parellel streams: one toward France, the other toward California.

At the SLAC National Accelerator Laboratory in California, each image is analyzed and, within 60 seconds after that image left the mountain, custom alerts triggered by specific research queries are delivered across the globe to thousands of networked astronomers.

Because of the immense and diverse number of celestial objects Rubin will track, ten million alerts will be issued on a typical night.

Understood as machines, these observatories chart a winding course back to the earliest flint tools. Understood culturally, they live within a continuum of objects that have altered how we conceive of our ever-emerging concept of world.

At every stage of humans' journey on Earth, we have been curious about what lies just out of sight. The invisible yet interdependent realities that our lives are secretly woven, forming a story held deep within us. This story is our cosmovison, one that gives shape to an ineffable idea of world, and the spiritual connections holding all we understand and believe in, valently together.

The function of these objects is not only underwritten by what they can achieve scientifically, but also by their meaning as poetic, empathic, human objects. The observatories are themselves beacons, living relics recording our collective desires, dreams, and accumulated knowledge.

The observatories of Cerros Pachón and Tololo are visioning tools that might be understood as psychic in nature - as techno-prosthetics proposing new ways of finding ourselves within the world. Stretching our perceptions, our cosmic vision.

Cerros Pachón & Tololo

30°14′40.7″S 70°44′57.9″W
Twelve Earths c. 2017-2029

Announcement Materials

With Support From

The Vera C. Rubin Observatory
Virginia Commonwealth University

With Special Thanks To

Ranpal Gill, Senior Manager, Rubin Observatory
Zeljko Ivezic, Director of Construction, Rubin Observatory
Steven Kahn, Former Director, Rubin Observatory
Robert Blum, Director of Operations, Rubin Observatory

With Extended Gratitude

Federica Bianco, Deputy Project Scientist, Rubin Observatory
Sandrine Thomas, Deputy Director of Construction, Rubin Observatory
Lynn Jones, Performance Scientist,Rubin Observatory
Emily Acosta, Media and Graphics, Rubin Observatory
Tomislav Vucina, Coating System Engineer, Rubin Observatory
Stuart Weinberger, Manager, Richard F. Caris Mirror Lab


Michael Jones McKean

Art Direction

Michael Jones McKean

Words and Concept

Michael Jones McKean

Web Design and Development

Seth Thompson, A Lot of Moving Parts

3D Modeling

Seth Thompson, A Lot of Moving Parts

Research and Design

agustine zegers

Copy Editing

David Kim

Video Editing

Julie Grosche

Drone Photography

Michael Jones McKean

Image Credits

Rubin Observatory/NSF/AURA, SAFRAN, Bruno C. Quint, H Stockebrand, Michael Jones McKean