The NIROSETI team with their new infrared detector inside the dome at Lick Observatory. L to R: Remington Stone, Dan Wertheimer, Jérome Maire, Shelley Wright, Patrick Dorval, Richard Treffers. Photos by © Laurie Hatch
"Infrared light would be an excellent means of interstellar communication," said Shelley Wright, an Assistant Professor of Physics at the University of California, San Diego who led the development of the new instrument while at the University of Toronto's Dunlap Institute for Astronomy & Astrophysics.
Pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from greater distances. It also takes less energy to send the same amount of information using infrared signals than it would with visible light.
The idea dates back decades, Wright pointed out. Charles Townes, the late UC Berkeley scientist whose contributions to the development of lasers led to a Nobel Prize, suggested the idea in a paper published in 1961.
Scientists have searched the heavens for radio signals for more than 50 years and expanded their search to the optical realm more than a decade ago. But instruments capable of capturing pulses of infrared light have only recently become available.
"We had to wait," Wright said, for technology to catch up. "I spent eight years waiting and watching as new technology emerged."
Three years ago while at the Dunlap Institute, Wright purchased newly available detectors and tested them to see if they worked well enough to deploy to a telescope. She found that they did. Jérome Maire, a Fellow at the Dunlap, "turned the screws," Wright said, playing a key role in the hands-on effort to develop the new instrument, called NIROSETI for near-infrared optical SETI.
NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed to for potential signs of other civilizations, a record that could be revisited as new ideas about what signals extraterrestrials might send emerge.
Because infrared light penetrates farther through gas and dust than visible light, this new search will extend to stars thousands rather than merely hundreds of light years away. And the success of the Kepler Mission, which has found habitable planets orbiting stars both like and unlike our own, has prompted the new search to look for signals from a wider variety of stars.
NIROSETI has been installed at the University of California's Lick Observatory on Mt. Hamilton east of San Jose and saw first light on March 15.
Skies cleared for a successful first night for NIROSETI at Lick Observatory. The ghost image is Shelley Wright, pausing for a moment during this long exposure as the rest of her team continued to test the new instrument inside the dome.