New Mexico History Museum
From Pinholes to Black Holes: Astrophysicist Ed Fenimore on How to See a Gamma-Ray Burst
FOR IMMEDIATE RELEASE
September 22, 2014
the New Mexico History Museum
Gamma-ray bursts may produce an extraordinary amount of light from the other side of the universe, but they occur so randomly that we don’t know where to look. We need a camera that can image the gamma-rays to locate them. Los Alamos National Laboratory scientists considered this high-tech problem and wondered whether a pinhole camera—the simplest tool of photography—might hold the answer. On Sunday, October 12, at 2 pm in the History Museum auditorium, astrophysicist Ed Fenimore talks about their solution: an array of 52,000 pinholes that is currently flying on the Swift satellite. His lecture, “From Pinholes to Black Holes,” is free with admission, and Sundays are free to NM residents.
Early in their research, LANL scientists developed a device with more than 20,000 pinholes that flew aboard the 1991 Space Shuttle. That coded array is currently on display in Poetics of Light: Pinhole Photography, an exhibit in the museum’s Herzstein Gallery.
The coded aperture mask aboard the Swift had its roots in the Vela satellites launched 50 years ago by LANL to deter nations from testing nuclear weapons in space. The thinking was that the universe was quiet and unchanging, so the satellites would easily detect a nuclear explosion. Instead, scientists discovered random and intense bursts of gamma rays that mystified them for decades. Some evidence showed that they were close by, meaning they were incredibly bright; other evidence indicated that they were in extremely distant galaxies, meaning they were brighter than anything previously believed.
They key to understanding them was to locate them. After experimenting with satellites, the pinhole camera came to the rescue. Scientists used many pinholes arranged in a coded pattern that produced thousands of overlapping images. Special mathematics allowed them to be unscrambled. To the untrained eye, the result was visually unimpressive: a point of light in a field of black. To scientists like Fenimore, it was the key that began unlocking knowledge about not only gamma-ray bursts but black holes, colliding neutron stars, and magnetic fields so strong that a cubic inch of absolutely empty space weighs thousands of tons.
The technique pioneered by Fenimore was used on French, Russian, Dutch, and American satellites to search for gamma-ray bursts and other mysterious cosmic events that reveal themselves only by sudden outbursts of x-rays or gamma-rays. Los Alamos designed two satellites (HETE and Swift) that used coded pinhole arrays that could locate gamma-ray bursts while they were still happening and alert optical telescopes around the world within seconds to search for the source. Such coordination eventually cracked the mystery by locating gamma-ray bursts in very distant galaxies. Only black holes are powerful enough to flood the entire universe with gamma-ray. The optical telescopes showed patterns consistent with the bursts made in jets emulating from the poles of a star as it collapses into a black hole.
Fenimore helps demystify the science of the cosmos while injecting it with his trademark passion and humor. Appointed a LANL fellow in 1998, he has won numerous awards for his work, including the NASA Group Achievement Award twice, the Los Alamos Distinguished Performance Award nine times, and the Los Alamos Distinguished Mentor Award. He was a member of the 2007 team that won the highest honor in high-energy astrophysics, the Rossi Prize. His work as a mentor has produced leaders in astrophysics in Asia, Europe and the United States.
What: “From Pinholes to Black Holes,” a lecture by astrophysicist Ed Fenimore in support of the exhibit Poetics of Light: Pinhole Photography
When: 2 pm, Sunday, October 12
Where: New Mexico History Museum auditorium, 113 Lincoln Ave., Santa Fe
Cost: Free with admission; Sundays free to NM residents