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Carleton Astronomer Designs Time Map To Be Sent Into Perpetual Orbit

December 19, 2012

Time Map on "The Last Pictures"

A photo of the time map created by Carleton professor Joel Weisberg. 

Northfield, Minn.—In a day and age when much of a person’s work and recreation is archived on various digital platforms, seemingly saved for long periods of time, a Carleton College professor’s project has been launched into an orbit that may last for billions of years.

Joel Weisberg, the Herman and Gertrude Mosier Stark Professor of Physics and Astronomy and the Natural Sciences at Carleton, created a time map that is attached to EchoStar XVI, which launched from a pad in Kazakhstan on Tuesday, Nov. 20 into outer space. The disk includes scientific messages designed by Weisberg to aid future explorers in understanding human’s concept of time. The time map is attached to “The Last Pictures, ” an archival disk created by artist Trevor Paglen, which will orbit the earth for billions of years affixed to the exterior of the communications satellite owned by the DISH Network. The artifact will remain in the Earth’s geosynchronous orbit in virtual perpetuity.

“One of the most profound things about this is thinking so far into the future. As an astronomer I’m somewhat used to thinking about deep time. I think a lot about the creation of the universe and billions of years is nothing to me. But, to be involved in a human undertaking that might last billions of years is humbling and fascinating,” Weisberg said. “To think about the natural processes that it might outlive, like star patterns as well as some stars and galaxies, is fascinating. I’m awed and delighted to have had this opportunity.”

Paglen and Weisberg collaborated on the messages’ design, which are inspired by the first messages sent into deep space aboard interplanetary spacecraft in the 1970s, while being updated by advances in human knowledge and understanding in the intervening decades. Weisberg and Paglen have written a scientific article, accepted for publication in Astronomical Journal, describing in detail the contents of the artifact cover and the reasons for the choices made in its creation. The article, "A Temporal Map in Geostationary Orbit: The Cover Etching on the EchoStar XVI Artifact," is also available on the scientific preprint server on the web at

“Astronomers have tended to believe there’s life out there because the universe is so big and there are so many stars, but it wasn’t until 20 years ago that we detected planets outside out own solar system,” Weisberg noted. “Now we know that planets are very, very common and that gives us hope that there is life. That doesn’t mean there’s intelligent life—we just know the universe is a gigantic place and there’s the possibility of life.”

To create the artifact, Paglen micro-etched one hundred photographs selected to represent modern human history onto a silicon disc encased in a gold-plated shell. The shell, designed at the Massachusetts Institute of Technology (MIT), contains the messages created by Weisberg. The pair met when Paglen was part of Carleton’s initial Weitz Center for Creativity exhibit in the fall of 2011, “Seeing is Knowing: The Universe.”

The project allowed Weisberg to step outside of his normal work at Carleton, where he is noted for his strong teaching abilities and inclusion of undergraduates in his ongoing research on radio astronomy, pulsars, gravitation, and the interstellar medium. He and his student researchers gather data at the Arecibo, Green Bank, Very Large Array, and Parkes (Australia) Radio Observatories. Weisberg has received numerous grants and funding from the National Science Foundation, as well as National Aeronautics and Space Administration (NASA).

“One of the joys of being at a liberal arts school is that we value these broader ways of looking at issues. It’s one of the reasons I love being here and that everyone loves being here,” he says. “This was a way to broaden my perspective; I believe whole heartedly in the liberal arts and I believe that broadening one’s perspective can help make one a better thinker, both in a broad sense, but also within your own discipline.”

It’s obvious after talking with Weisberg about the project and process that it energized him as he moves towards his third decade on the Northfield campus.

“The whole process of thinking of things in terms of deep time was fascinating,” Weisberg said. “Even if it’s not discovered, it’s another expression of human thinking, human talent, human capability. It’s an expression of what we can conceive of today. In a sense, it’s like our or any other creative activity.”

Paglen developed The Last Pictures through years of research and consultation with leading philosophers, scientists, engineers, artists, and historians and through a residency sponsored by the Visiting Artists Program at MIT. The project originates from the idea that the communications satellites in Earth’s orbit will ultimately become the cultural and material ruins of the late 20th and early 21st centuries, far outlasting anything else humans have created.  These geostationary satellites, located above the equator at an altitude of 24,000 miles, experience no atmospheric drag, and will remain in orbit until our sun expands into a red giant and engulfs the earth about 4.5 billion years from now.  The Last Pictures imagines a future Earth where there is no evidence of human civilization beyond the derelict spacecraft we have left behind in our planet’s orbit.

“Maybe it will never be discovered, but the process of creating it is fascinating, and for me, a profound experience.”

Written by Eric Sieger, Director of Media Relations